Author: Shaun

Preparing Utility Room

One of the first jobs was to move the existing electricity control board from over beside the window and position it out of the way on the dividing wall between this room and Bedroom Three and reconnect some of the electric cables so they were all out of the way before we could fill in the walls with rock wool and cover it up with the vapour barrier. We also did some extra lighting for our hallways, see Installed Lighting Along Hallways. We then started preparing the Utility Room to be created with all its equipment, pipes, valves, pumps, tanks etc. that will serve the house and one of these items was to create an air outlet vent that will allow the exhausted air to escape the house and we did this by chopping our way through the 200mm thick foam insulation near the ceiling and near the left side of the “E” wall as you stand inside the room. The hole we made was the full width between two wall legs, some 550mm wide and a height of 600mm, reaching the cement board outer skin layer where we sliced a 450mm wide by 500mm high hole through the 10mm thick board. We had some stainless steel woven mesh (left-over from replacing our filter in the rain water filtration system), the mesh is woven with fine wire and has 2mm holes which should stop almost all insects and animals from entering the dangerous zone of a fast spinning blades of the air fan. We used some MS Polymer black glue to attach the mesh to the inside surface of the cement board and held it in place using a plastic covered piece of OSB board with clamps to keep it firmly pressed tight while the glue cured.

Gluing-the-HVAC-exit-vent-mesh

Next, we took some of our left-over 18mm floorboard chipboard material and created a box that will form a large square duct that will help guide the air out of the building. It measures 450mm by 500mm to match the hole through the cement board and put on a ring of 50mm wide strip to provide a larger surface area to bond to the outer perimeter of the wire mesh. The whole box extends well beyond the thickness of the wall so we have options to how much we need when we connect the rest of the ducting and fan later on. Talking about the fan, got one of our new 300mm diameter fans and temporarily seated it inside the new vent hole and powered it up. We did some test runs with different air flow rates and went outside to listen to how noisy it was. We even got out our sound level analyser and took some readings. So at maximum air speeds, we were getting a reading of 63dB at a distance of about 2metres and 65dB and 68dB using different settings on the analyser, representing different patterns of sound pressure and frequencies. The background noise at the time was 40dB, it wasn’t very windy at the time. These figures are quite loud but this was for the maximum possible speed and the sheer power of the fan is that we will only need that kind of air flow rate during the very hottest times of the day in the middle of Summer. Most of the time, the fan will be running much more slowly and we think that it will be about 50dB which is a quiet murmuring noise that fades away when we moved some 5 metres away like the front door or out in the Loke.
Oh yes, just to make clear, the outside layer of Larch timber was still there, the air was escaping through the gaps between all the planks and it seems to be working very well. It gives us the benefit of having somewhere for the exhaust house air to escape but not having a ugly large metal grill visible.

So upon the good test results of running the fan, we proceeded to glue the wooden box ducting into place and filled around the edges with more foam boards, using PU spray foam to stick the whole lot together.

HVAC-Exit-vent-1

HVAC-Exit-vent-2

The next job was to insert a long awaited conduit that needed to go from the concrete floor level and all the way up to the Eves, to provide a water irrigation supply for any hanging plants etc. We positioned this conduit near the copper water pipe already installed some weeks ago. There were a couple of other conduits that we also extended and positioned so they were poking out into the room, these were the mains socket in the wall and a couple of underground connections too. Another little task was to screw and glue a vertical CLS post in the corner, the E-F corner to provide a mounting leg for the wall boards when they go up later.
Because the Utility Room has lots of cupboards, a worktop and the door and window too, this meant that there was virtually no where to put sockets and other switches etc. so we decided that we didn’t need to employ the same design of creating a Utility Channel running around the whole room. It is a bit ironic not having one of these channels, called a Utility Channel, in our Utility Room! Oh well. We did realise that we would like a switch beside the Side Door entrance so we could activate the lights or trigger the garage doors to open if we were going that way, so we embedded two short CLS pieces between the wall legs that is sandwiched by the door and window, to form a pseudo Utility Channel. Oh yes, We remembered to insert another piece of conduit that went down to the concrete!
Another preparation task was to go around and plane off all the little sticking edges of the plywood that formed the wall leg structure, there are three of these plywood pieces for each leg and some of them are proud of the leg itself and we need it to be all smooth and ready for the wall boards to go up next week.
Another job that needed doing was measuring and making horizontal rails for the bottom and top of the window and the top of the door too. These rails are the exact position that defines the height and hole of the window at 500mm from the floorboards and 2200mm at the top, also the same for the door too. But we don’t have the same utility rails that other rooms have, we had to fit them inside the framework instead and there is already pieces of CLS timber in place but only approximately at the correct position. We needed to create a special piece for the window, a 45mm to 47mm high piece for the bottom rail and a more even 30mm piece at the top. The doorway was easier and a normal 63mm piece went in straight. Well perhaps not easier after all, because we discovered that our temporary door was too tall and hit this new framework piece. This led us to having to deal with the door itself next. We took it off and decided that while it is off, we would go ahead and install a new temporary door sill, to make sure that we will get above what will be the new floor surface when we put down the floorboards. We found a piece of “4by2” treated timber, cut it down to 1040mm length, to fit the width of the doorway, levelled it off by using a couple of solid 5mm plastic spacers and a smaller 3mm one in the middle and fixed it into place using three concrete screws plus a heap of MS polymer glue to seal the outside joint to provide some water protection against future rain floods.

Temporary-side-door-sill

Now that we had the new sill in place, we could measure the amount of material we would have to remove at the bottom of the door, some 45mm in total. We put in an replacement CLS frame to ensure the bottom of the door was still reasonably stiff. Then we chopped off 10mm off the top to clear that new upper rail and then put the door back. We did have to do further adjustments by running the planer across the bottom edge as the door turned out not to be exactly square but since it is only a temporary door, we kludged it to get it to fit without scraping!!

Finally, we were in the position to do the next stage of filling in the walls with glass wool and the plastic vapour barrier membrane. We scrubbed the aged timber surfaces along the bottom, applied a line of the butyl heavy duty double sided sticky tape along the bottom edge, around the window and along the top edges too. Where there were a plastic layer already, we used acrylic sticky tape instead. Next, we unrolled and cut up lengths of glass wool pieces, 100mm thick stuff for the lower half and longer pieces of 200mm thick stuff for the upper sections. We filled in the corners and around the door and window so everything is now filled in.

Fibre-in-utility-walls-1

Fibre-in-utility-walls-2

After that, we put on sheets of plastic to encapsulate the yukky glass wool stuff and provide a vapour barrier to stop condensation from forming in the body of the wooden walls and hence avoid potential rot problems.

Utitlity-walls-with-vapour-membrane-1

Utitlity-walls-with-vapour-membrane-2

We now have finished covering up the walls, just a little bit to finish off like sealing around the air duct and various conduits sticking out, plus finishing off the window and door too. Then we can install a layer of plasterboard to cover up this plastic to provide a fire resistant barrier and then we can start on building the internal “cupboards” that will contain the equipment that provides the utilities and services for the house.

28 August 2021
Temporary Lighting Installed Along Hallways

With the days drawing in and as each room is completed, less and less daylight is reaching the inner hallways and they are getting gloomier and gloomier plus also part of moving everything out of the Utility Room, sorting out the wiring, we decided that the hallways on the ground floor needed additional temporary lighting installed. We had a collection of small 10W LED flood lamps, eight of them in all, and proceeded to distribute them evenly around our four lengths of hallways. We used some old 1mm twin and earth lighting cable to join each one up and connect the tail end back into the light switch beside our side door.

Temporary-hall-lights

We now have a brighter future in our hallways!

24 August 2021
Wall Boards All Up and Utility Channel Cut

We resumed the work on Bedroom 3 with the Wall Boards. We switched over to the tongue and groove method of joining two boards together and it seems to be working quite well. It is a simpler process of getting the two board to join as there are no loose biscuits to keep an eye on, just solid a tongue and getting it to slide into the groove is the only little troublesome aspect but nothing much really to worry about. The whole room is now covered with the 18mm thick OSB sheets.

Walls-covered-in-OSB-1

Walls-covered-in-OSB-2

Walls-covered-in-OSB-3

The window holes were trimmed to remove the excess sticking out edges of the OSB boards and then using our track saw, we went around cutting the Utility Channel slot too. The green laser line generator gave us the 800mm and 900mm off the floor surface which is where we have our Utility Channel positioned and we did the standard spacing (being 38mm) to stop each channel to avoid crowding the corners and windows plus doors.

Utility-channels-cut-1

Utility-channels-cut-2

Utility-channels-cut-3

We also put on smaller side pieces of OSB boards around the en-suite entrance so that the glass wool is all covered up but also ready to build the finishing surfaces that will support the glass wall and glass door.

En-suite-dorrway-lined

We then installed a dozen electrical double sockets around the room as this room will become our new work area for the duration of the house build.
The last two days were spent moving the entire load of tools and supplies including two sets of shelves, a stack of drawers and several tables from the Utility Room to Bedroom 3

Everything-moved-from-Utility-1

Everything-moved-from-Utility-2

Everything-moved-from-Utility-3

Then a good clean up of old rubbish, saw dust and other chunks lying about.

Utility-emptied-1

Utility-emptied-2

Utility-emptied-3

We put up five more quick shelves in our Knick-Knack cupboard so we could spread out and organise all our plumbing bits and pieces, to be ready to hand when we build the various water and waste pipework. We also brought from downstairs our little work table we had set up for making the plastic air diffuser and put this operation in with the rest of the tools and work tables in Bedroom 3.

Plumbing-supplies-sorted-1

Plumbing-supplies-sorted-2

We also had a general sweep-up of the hallway and this means we can start work on finishing the walls in the Utility room, start building the floor support framework and start mapping and designing the placement of the various pieces of equipment that will drive the environment for our house like air, water and electricity.

21 August 2021
Wall Boards Are Going Up and Final Conduits Installed

After having finished the floorboards for Bedroom 3, we can walk around much easier and inspect everything. We decided to swop out the cable conduits around the windows with our recently purchased rigid waste piping and also insert a another new piece of conduit, this time to provide access for power and signalling cables to the windows and their motorised blind mechanisms. We nearly forgot all about those!

Replacement-window-bypass-conduit

Window-control-conduits

Another feature that we have been talking about is putting in a built-in hearing induction loop into and around the walls so we installed another length of conduit, running horizontally above the doors and windows using our stock of 20mm black polyethene pipes. We had to heat and bend much sharper corners because of the tight space requirement when traversing around the corner and having to keep inside the 38mm spacing limits. We made six of these tight bends and then used short 25mm diameter pipe to join them to the straight sections. The Loop started and finished at our Control Box which will house the induction loop amplifier. This is a very rare feature to have such a thing in a domestic situation, all built-in but having two people wearing hearing aids living here, we thought we had better provide the ability to install a loop later on.

Conduit-for-hearing-loop-1

Conduit-for-hearing-loop-2

Then we used the left-over flexible 32mm conduits to put in the connection for our mass of low-voltage cables to start on each side of the entrance way.

That concludes all the conduits for this room, we didn’t need to install a conduit for compressed air nor any other types like water or things like that. So we moved on to the next task of building the short stub wall and doorway to the en-suite. One of the first steps was to screw up a long piece of CLS 63mm timber at the 500mm height which matches the two windows in the room. We did this by using our green laser to ensure everything matched up. Then we measured to how far the toilet bowl would be sticking out from the wall and made sure that the door would be able to swing clear. It does mean that the doorway is slightly off centre but not by too much, some 410mm on the left side and 610mm on the opposite side. We used more of our “2by6” timber that we originally used to build the framework around the en-suite entrance, to make the stud wall and a flat top. We aligned the height of the little stud wall to the new horizontal rail we just put on so all three window like objects in the room all look very similar, with an oak sill on each one etc. We planed two pieces so it was nice and flat to go across the top of the stud walls and two vertical pieces underneath this flat top and goes all the way down to the footplates on the concrete. These were glued and anchored into place with lots of screws plus several battens too. The last piece of the 2by6 was to create the door sill sandwiched between the two stud walls, exactly 880mm wide which is our standard width for swinging type doors. We introduced a very slight slope to this door sill, dropping down by 5mm as one goes into the en-suite so that if there is a lot of water splashing about in the room, it is not prone to running out and into the bedroom.

Ensuite-stubb-wall

The next task is to slice up our heap of 8×4 MDF sheets into eight strips of 149mm wide per board, these strips go at the bottom of the walls to provide the back-panel to our air channel distribution system running around the bottom of the wall, completely all the way around the whole room. We went from post to post along the wall, stopping and starting on them to ensure that the ends didn’t flap in mid-air. We fired in staples on each post but also glued the top edge to the underside of the CLS horizontal rail so it kept the strips straight and sealed to stop air leaks. Talking about air leaks, the bottom edge was sealed using a black MS Polymer glue against the floorboards. Then we went around with a paint roller and painted the bottom section of the strip black to stop any chance of a gleam shining through when the room is finished and carpeted.

Air-channel-backing-board-1

Air-channel-backing-board-2

Painted-black

The next job was to put up the wall boards, the 18mm OSB sheets. Before we put them up we inserted the final layer of glasswool insulation between the horizontal rails, this is roughly fitted and is really just to provide impact sound dampening for the wall.

Final-layer-of-Insulation-1

Final-layer-of-Insulation-2

Also, we went around measuring the height of the walls, from floorboard to ceiling joists and it came out to be 2415mm on average, fluctuating only a couple of millimetres. This height was designed so after the 15mm thick ceiling fermacell panels is installed, the room will have around 2400mm clear, about 7feet 10½ inches.
We then looked at the various methods of putting up these wall boards and we went for the more rewarding results by putting whole OSB sheets vertically from floor to ceiling in one go (instead of splitting it up into two halves, separated at the Utility Channel) and then cut out the Utility Channel afterwards and also deliberately overlapping the doors and windows so we can trim back the edges right back to the physical limits of these holes in the walls and get a much better finish. The next choice was how we would join the sequence of boards and part boards together along a wall section, we could either use a biscuit jointer or use a continuous tongue and groove method. We couldn’t decide so we went for the biscuit joining method first on the short wall that has the small window in it and proceeded to put in ten biscuits along the entire height with includes the extra ones around the bottom and top pieces that covers the window section. It was a bit fiddly in getting all the loose biscuits in and then slicing the two boards together but it was workable. The big problem we had was with the glue as it was taking us a good 15 to 20 minutes to get all the pieces ready, with their joints and biscuits and we were using the PU spray gun glue foam because it was a very handy tool to just spray the glue into place, but these spray expanding foam don’t have a long “open” working time before skinning over, even this especially designed foam to work more like a glue still has a short time before it skins over and cures. We did manage it by doing it in stages and we got the first wall up and screwed in place. That is another thing, we decided to use screws instead of nails, just like the floorboards because we wanted to know that the boards were being tightly pulled back onto the support horizontal rails and squeezeing on to the glue.

We needed a glue which stayed usable for longer and after much discussion over different glues, and doing several tests (we put out three blobs of each glue, and then waited 5minutes, 10minutes and 20minutes to see if and when they skinned over and whether the joint was affected by screwing in small pieces of MDF material), we concluded that the solvent-free construction glue was suitable because it is both cheaper and less messy than the other choice of the PU construction type which worked the best (and the third glue, the Skixall performed the worse because it started to skin over by the 20 minute point but still did a good strong joint).
Before we resumed putting up more wall boards, we felt that we should make sure that we could cut out the Utility Channel so we got our track saw out, drilled a series of mounting screw holes and then using our green laser line generator, mapped out on the finish wall the 800mm and 900mm levels, drawing two lines. We also decided that there will be a 38mm uncut area at each end of the channel so that the covers didn’t have to go right into corners or right up to the edge of a window or doorway. We then proceeded to mount up the track guides onto the wall and sliced two horizontal cuts into the OSB board, then finishing off the cuts using our wiggle saw. After tidying up the cut edges with sand paper, we now have our first Utility Channel ready for use, for our sockets and speakers and whatever else we may want in a room.

First-walls-OSB-installed

Another little job we did was to make a magnetic clamping system for our green laser line generator because it would be much easier if we could put up a vertical metal ruler with pre-determined positions of various elements we have in a room and be able to move the laser up and down easily without having to use a clunky screw clamp. So we put on a long metal band on a piece of wood and glued in two strong magnets into the laser’s little shelf. We did have to add a coat of a rubber like spray on paint to increase the friction between the metal and magnet as it had a tendency to slide down under the force of gravity!

Finally, for our next section of wall, along the “H” wall with the large window in it, we decided to try out the tongue and groove method of joining the boards together and see how well (or not) it performed. We got our two router machines out and set up the two cutters, one to make a groove 13mm deep and the second one to cut a tongue 12mm long. These are parallel straight 90degree tongues so it may give us some fitting issues when we get to try it out next week. The machines are now setup and the test pieces look good and form flat and smooth joints so it is promising.

Tongue-Grooving-edge-of-OSB-1

Tongue-Grooving-edge-of-OSB-2

The last thing we did was to bring in a dozen more sheets of our 18mm OSB boards from our storage piles outside under canvas, we will need at least eight more boards to finish off Bedroom 3.
Oh yes, we moved some of our LED flood lamps from upstairs and mounted them into the back bedroom where we have all the sheet materials and several lamps in the room we are doing because the place is getting darker with the rooms being built and blocking off light in all directions!
Next week, among entertaining family members, we will continue putting up wall boards and even maybe a layer of the fermacell (plasterboard like material) on too and get to see an almost completed room, apart from the ceiling and the doors for the en-suites etc.

13 August 2021
Floorboards Installed plus Various Wall Conduits Laid in Place

Continuing with Bedroom 3, this week we installed more various elements into the wall and floor structure to provide additional functionality to the operation within the room like, for example, a control box that will contain the electronic controller, a display module and local circuit breakers for the power lines. This was constructed from sheet of left-over 12mm thick plywood board material and made two open faced boxes, measuring 360mm wide, 75mm deep and 400mm high.

We designed it this way to allow the shell to be fitted into the wall structure but not too deep to intrude into another mechanism like the sliding door modules. These boxes will be covered up by the wall boards, the 18mm OSB sheets later on but will have internal brackets and fuse holders plus a display unit with built-in audio amplifiers to help drive the four speakers that will be the standard provision in this size of rooms.
The next task was to drill 20mm wide holes for more conduits to connect to this buried box and through the utility channel too and plus another one going up to the ceiling to serve the lighting circuits. Talking about conduits, we installed a couple of extra ones either side of the entrance to the room, these being 20mm diameter pipes, to help thread the mains AC power lines in and around the utility channel. At this point, we have still the problem of having a flexible conduit that also needs to go either side of the entrance, this time to supply bunches of network cables, speaker wires and other low voltage signalling cables. Our supplier of the 40mm wide twin-walled conduits still have not arrived so we have been looking around for alternatives. It looks like that we will have to use rigid plastic plumbing pipework, the 32mm diameter size that is usually used for waste water plumbing but we could use that, coupled with sweep bends and achieve the method of channelling the cabling around our windows but we would still need a flexible solution and the nearest type we can find is a corrugated water hose being sold in 10metres length and 32mm internal diameter and this would be used at the entrances and going around en-suites etc. We will place an order for those solutions soon.

In the meantime, we started looking at our air distribution system, the four separate orange 63mm ducting that will take the air to all edges of the room. We mounted our air splitter chamber in the entrance way so it is ready to be connected to the main air duct when that is constructed, and the four outputs were then connected to lengths of the orange 63mm twin-walled conduit. These conduits travelled across the room, cutting paths through the rigid foam board that covers the hot water pipes and anchored to various floorboard support legs and arrived in approximately the middle of each wall.

Distributing-air-around-the-room

Next was to design an sweeping adaptor that will take the output of this orange ducting and split the air into two sideway facing wings to send the fresh air along just behind the wall boards. We had thought that we could design a model on the computer and generate the object using our 3D printer but it turned out to be quite a complex shape sweeping up, backwards and then forward and sideways, all because the air duct is underneath the floorboard, has to go around the back of the support framework and arrive above the floorboard level but hidden behind the wall board. There were seven individual parts to make it possible to generate each 3D part on the printer (because of the limitations of building up the plastic object layer by layer so it is very very difficult to create hollows or bridges without it collapsing or having internal support structs etc.) and it would take well over 24 hours to just print one of these winged adaptors.

3D-diffuser-feed

We needed lots of them all over the house, at least fifty of them! So an alternative solution was needed and it found it by using the waste water rigid plumbing pipes, the solvent weld types, not the push fit ones. We took a series of 90degree bends with short straight pieces and created a fair substitute design that does the same job of channelling the air out and sideways behind the walls and into the room. We sliced little bits off various parts to reduce the size, trying to make it as compact as possible and eventually we applied the solvent and glued it together. It is a twin pipes going up and then turned to form the two outward facing wings. Finally, we took short lengths of the rigid 68mm brown pipework and experimented in heating it up with the hot-air gun and using various shaped wooden moulds, we could stretch the plastic out and then squeeze it down to wrap around the two 40mm pipes of our adaptor.

Pipe-flaring-tool

Pipe-shaping-tool-inner

Pipe-shaping-tool-outer

Shaped-Splitter-pipe-

Protoype-air-diffuser

We then did a test run by fitting it into the wall, underneath the large window in the room, placed two strips of the MDF strips (with little cut away sections) and screwed it up to the wall legs. We found two narrow pieces of our 18mm OSB left-over pieces and also screwed them on the horizontal rails so we created our air channel hidden behind the wall board. We connected the orange ducting up to the new adaptor and connected our old 150mm centrifugal fan to the main air splitter chamber to give it a blast of air through the system. We could feel the air gently sweeping along behind the OSB strips and gently entering into the room itself. We wanted to make sure that the air would gently distribute fairly evenly along the whole wall and had thought that we may had to cover the air channel with a cloth barrier to help guide the air to spread out but it turned out to work just fine without any additional cloth barrier after all.

Prototype-in-place

Test-channel-at-base-of-wall

We then found some old pieces of underlay and carpet to place on the floor (just a sheet of 18mm OSB board that we are using to help us safely negotiate the floorboard support framework) and had a look at the finish results. The first implementation of the wall boards is positioned to allow a 50mm (a 2inch) air gap between the floorboards and the bottom of the wall board, to provide room for the air to escape and have our carpet fixed down in the gap. But we decided that 50mm was too big so we reduced the gap down by 12mm to just 38mm and looks much better. the air was still escaping out quite easily even with the carpet in place too.

Carpet-under-50mm-gap

Carpet-under-38mm-gap

While we were doing our experiments, we ordered all the parts to make plenty more of these air divertors, some 450 pieces, a mixture of sweep 90degree bends and 90degree elbow bends plus also a pack of grey pipes too, all for overnight delivery. We made a jig to hold the parts whilst they were glued, This meant that we did proceed to make a further three adaptors and proceeded to install them into Bedroom 3, one under the smaller window, one along the section of wall just beyond the en-suite and the third one in the middle of the wall that is shared with the Utility room. We trimmed the orange ducting, applied sealant glue and therefore formed the ventilation system for the whole room.

Final-air-diffuser-design

We also ordered 20 sheet of 6mm MDF board, paying a ridiculously high price for them (the world has gone mad for timber products!) and these will serve to provide the smooth backboard to the air channel. We will have to paint it black to reduce the gleam peeping out from under the wall edges.
Another change of an implementation design and strategy was the cold water pipe. We had used the 28mm white plastic pipework that is designed for domestic water, especially hot water because it has a metallic barrier moulded into its wall thickness to prevent dissolved gases from “upsetting” the plastic material and forming weakness after a decade or so. But this kind of pipe is rather expensive and we need lots of it to provide our hot water circulation system. So we decided to swop out the 28mm cold water feed and replace it with 32mm polyethene water pipe instead. The pipe is much cheaper and even the T-junction adaptors are half price too so now we have a blue coloured pipe running from the Utility room and reaches the access chamber where we will have all our connections done to serve the en-suite basin, cistern and shower.

Once we have doubled checked that everything is laid out, all the conduits, pipework and air ducts are in place under the floor, then we brought in loads of the shredded chopped up pieces of our left-over PU foam board and filled up the void and empty space in among the legs and pipework. We moved about two thirds of the content of our giant bag we got outside and filled the space to the level of the floor joist.

Filling-the-undefloor-with-Scrap-insulation-1

Filling-the-undefloor-with-Scrap-insulation-2

The last day, the Friday, we tackled the task of laying down the proper set of the 22mm thick tongue and groove floorboards. This chipboard material was laid in the long direction, starting at the en-suite side of the room, slicing off the tongue so that the full thickness is fully on the framework around the edge of the room. We also sliced off the tongue at the beginning at where the entrance is so that would be ready to butt up when the hallway own floor is constructed. We put down three rows to see how it came together and everything looks good so we lifted those pieces up (they weren’t screwed down) and put in the finishing layer of glass wool to fill the final void directly under the floorboards to help deaden the sounds as much as we can do. The chipboard pieces were then placed back into place and this time, screws, three of them in each joist and also more around the edge of the room too. We put down 6 rows plus a little narrow strip to finish over by the large window. It was tricky to get the ends of each row in as the tongue needed to be inserted into the previous board’s groove but also to move pass the lowest horizontal rail on the wall too. This was especially true for the last narrow strip and we had to rasp a clearance slot where the wall posts were, just in order to get the tongue to engage fully into the groove. But we got there!

Then-topping-with-100mm-glasswoool

Bedroom-3-Floor-finished-1

Bedroom-3-Floor-finished-2

That sees the flooring all completed now so we can now look forward to be doing the walls next. It is nice to see a room taking shape.

6 August 2021
Continuing Putting Together Bedroom 3

We continued with the work on Bedroom 3 and getting the floor, walls and windows ready. Whilst we are waiting for the deliveries, we got on with finishing the windows by putting the plastic vapour barrier around the bottoms and tops of the two windows. The first task we did was to insert small pieces of 25mm thick foam boards to encapsulate the last exposed bit of the concrete wall under the window and this will reduce heat losses and avoid condensation inside our window module. It was then a case of bending and folding the plastic up and over down into the chamber and back up again towards the oak frame under the glass. A slab of OSB 18mm thick board was then fixed into the bottom of the chamber to provide a mounting surface for the mechanical elements for our automatic blinds that will go up between the two pane of glass. The other piece of the black plastic was then inserted at the top end of the window to basically do the same job of sealing the wall structure from condensation derived from wet air generated by us human beings. The second smaller window was also done in a similar manner.

Vapour-barrier-in-base-of-window-1

Vapour-barrier-in-base-of-window-2

Vapour-barrier-in-base-of-window-3

The next job was to attach a line of left-over CLS pieces to run all the way around the room at the ceiling level. This line of CLS timber will support the top of the OSB wall boards, with a short section having had the timber planed down to remove 11mm to cater for the extra strong lintel we built over the large window that is needed to support the first floor joists etc. Then we did the middle support rail as well so that concludes the majority of the support CLS timber all around the room. The next short pieces are going above and below each window and above the main door and the en-suite too. The height of the upper rail will define the internal framework for the structure of the doorway and this distance is 2206mm from the floorboard surface. This will give us room to insert the Oak frames and provide clearance for the flooring covering (like carpets etc) and have a 7foot I.e. 2134mm tall doors.
The windows also are set at this height so that both the windows and doors will match up with their openings, with the seats for the windows themselves will be set at 500mm off the floorboards. The seat will probably be 20 to 24mm thick Oak planks glued together and in the order of 365mm deep with a bull nose front edge sticking out into the room by 25mm or so.

Last-two-rails-installed

Then, still waiting for the delivery of our conduit tubing (we enquired and the supplier is having trouble in sourcing the 40mm twin wall conduits), we got on with doing the side walls for each window. A piece of CLS timber is needed at the back to extend the original framework around the window so that there will be sufficient support to hold the second oak frame that will hold the inner pane of glass . We had do some major planing of these timber pieces to make them line up with the original CLS so that the new oak frame will match up together. Long screws were drilled and driven through the full depth of the 63mm direction, to secure each piece into place. then yet another piece of CLS timber was placed, but this time at the front of the window section, just behind the horizontal rails, to form the vertical corners of the walls where the windows are inset and the fermacell “plaster boards” will provide the finishing surface coming along the wall and turning in towards the windows.

Window-sub-frame-exstension

Window-side-panel

One of the other tasks we did this week for this Bedroom, was to drill clearance holes through the horizontal timber pieces that forms the space for the Utility Channel and these holes had short length of various sizes of conduits and pipes inserted. These conduits helps to transfer the cabling from one side to the other of an opening like a window or door, to the other side so that the cables can carry on around the Utility Channel. There were 20mm diameter polyethene black pipes to carry the mains AC 230V supply and a second larger diameter plastic conduits measuring 37mm overall but 32mm internal, to carry all other types of cabling like network cat5, speaker wires, DC voltage power and other low-voltage types. We did the doorway around the en-suite plus also the two windows too.

Conduits-fixed-to-base-of-utility-channel

Conduits-bypassing-the-window

At last, our Flexible Twin Walled Plastic Conduits Arrives, but only our 63mm and 100mm types. We are missing the 40mm diameter one as it is in very short supply across the country and beyond. We are looking for alternatives to help us guide our low-voltage cabling around windows and doorways, we had some old wide bore water pipe so we used that one instead (it is the green ones).

Now we could and did design and construct an air conduit splitter module (a plenum), which takes the 100mm feed coming from the main air duct, and splits the air flow into four separate 50mm streams to go off across the room to the four walls. We used left-over chipboard floorboards to build a triangular shaped chamber which squeezes from a 100mm gap, down to a 50mm spacing to spread the air out sideways, into four holes. The five holes all had short lengths of plastic pipes inserted and glued into place so we can just slide the conduits straight in and out to provide a good strong and tight seal. There were four 68mm wide pieces of pipe plus one 110mm wide sewage pipe, all ready for installation later on. We also did a small test of different glues and sealants to make sure that the plastic pipes we have used will stick to the twin-wall conduits and we can happily report that all four types we tried all worked just fine (PU sealant, PU construction glue, general purpose construction adhesive called Grip Bond and a modified polymer one called Stixall).

Testing-joining-pipe-to-twinwall

Room-air-supply-plenum-1

Room-air-supply-plenum-2

Room-air-supply-plenum-3

The other task, the final one for the week is to slice up a sheet of our fermacell material, a gypsum mixed with recycled shredded newspaper board material, into 175mm wide strips so we can insert a backing panel in our Utility Channel, to both provide a surface to mount hooks and other lightweight items but also the fermacell layer will provide a fire resistant barrier to stop the spread of flames. So we took a sheet and sliced it up on our workbench table saw, set the fence to 175mm and cut six strips off one sheet. We went around the entire Utility Channel fitting each section with our new strips, occasionally having to trim the edges to make it fit and also in one section, we had two 20mm conduits sticking out the wall and had to drill a hole in the correct spot. We used the general purpose construction glue along the bottom and top edges, plus a line on each vertical leg and did the occasional vertical joint between fermacell pieces too.

Back-of-utility-channel-covered-in-Fermacell

Exterior-conduits-passing-through-back-cover

Another little job we did was to try out a test fit of some 6mm thick MDF board material to see how it looks and how it comes together, all to form the air dispersal channel running around the bottom of the wall, all the way around the whole room. We concluded that it will do a very good job so next week, we can look into doing that job.

31 July 2021
Flexible Twin Walled Plastic Conduits Arrives

At last! The arrival of the twin-walled plastic conduits tubing has occurred today this morning! But not all of it! We ordered three different sizes: 100mm, 63mm and 40mm diameters but there seems to be a country wide shortage of the 40mm size and our supplier has been waiting to see if any would come in their own warehouses. But after we had made enquiries and explained to us the situation, they split the order up and sent us the two larger sizes with the smaller one pending, maybe in a week or so if they can source the conduit from Europe.
So we now got two 25metre rolls of orange of the 63mm (internal size of 50mm) and one roll of 25metres purple 100mm (93mm internal) conduits, ready to construct our air circulation system, the 63mm one to help supply fresh air to all four walls in each room (under the flooring) and the 100mm tube to take away the old stale air inside the ceiling.

Twin-wall-duct-arrives

Twin-wall-100mm

Twin-wall-63mm

The smallest size, the 40mm one, we would like to use to guide the electrical cables around the obstacles like windows and doors, connecting each sections of the Utility Channels running around the room, but if we cannot get this type, the twin-walled conduits, we will have to find an alternative design and perhaps one option is to find a supplier of vacuum tubing or maybe the cheaper end of water hoses.

30 July 2021
Stair Lift Motor, Gearbox, Chain and Controller Arrives

This Monday morning saw the arrival of the electric motor, the gearbox, chain, cog wheels and the electronic controller. All this equipment is going into the Stair Lift unit to drive a moving platform system for our stairs. This device will help people and objects climb to the first floor and back again. We always wanted a stair lift design that is built into the fabric of the house, rather than a ugly bolt-on solution that virtually everyone else has to have. So we went for a flat-bed platform design as oppose to a chair, thus enabling a person in a wheelchair to have independent freedom to go upstairs at their own convenience and also allow the transport of larger and heavier items to be lifted up (or down) to the first floor.
To this aim, we designed and measured the power and torque needed to lift 250kg at a speed to give a journey time of 5 seconds. The weight has to include the mass of the platform and its support framework and wheels, we couldn’t design in the counter-balanced weights to cancel out the platform because there was not enough room to have another moving solid ballast hidden and safely out of the way of fingers etc. But the electric power to drive the combined load is only for an occasional use and the cost will be minimal in the long run.

StairLift

The motor is a 3-phase AC 240V 1.1kW type that bolts into a heavy duty 15 to 1 ratio gearbox, a worm drive design that has the built-in advantage of providing a brake to hold the platform when electricity is lost to the motor but we do also have other safety measures incorporated into our design too. The gearbox will drive a 25mm thick shaft that will go out to the two cog wheels which in turn will drive the 11metres 3/8inch chain which in turn is attached to the platform.

Lift-motor-and-gearbox

Drive-cog-and-chain

Shaft-bearing-and-idler-cog

The electronic controller, called a Variable Frequency Drive (VFD), which is a high voltage sine wave generator and produces three separate outputs to drive the motor, with a variable frequency range from 1Hz to 60Hz. This changes the rotation rate, whilst maintaining full torque.

Variable-speed-motor-drive

We did some electrical tests but we discovered that the electrical filter design in these VFDs has a bad side-effect to the regular domestic RCD safety switches we have and kept tripping them. After some research on the web, learning about this design philosophy which is all to do with suppressing electrical noises being generated by the inverter and the motor, so unfortunately these industrial class of equipment needs a direct connection to the mains electricity on their own circuit and fuse breakers. We don’t have one of those which means we need to hire an electrician to come and add another consumer unit to our mains switchboard before we can carry on testing the motor etc.

26 July 2021
Started Work on Building Flooring Structure for Ground Floor Rooms
We started the new week, after completing our staircase in just four days, by fixing up the metal joist bracket to the stringers at the top of the stairs. We had already made two triangle wedges and they were glued in on Saturday. The metal bracket was only screwed up this time because we want to have the possibility of moving the whole staircase when we come to install our stair lift module later. We are not sure yet whether we will have enough space either side of the stringers to mount cog wheels and other materials to build the parts of the stair lift. So the joist bracket are just screwed on and not glued ..yet!

Bracket-holding-up-stairs-1

Bracket-holding-up-stairs-2

So onto the flooring job, we got out our green laser line generator and sat the device in the middle of the crossroads of our hallways and adjusted the height until we got the green line shining right on the 10metre mark, this being our Ground Zero line. We already had an 11metre mark on the metal leg “number 5” that is our reference point for the whole house so we measured down one metre for our ground zero, this will be our flooring level for our ground floor. We now have marked all the doorways (Kitchen, Great Room, Bedroom 1 & 2 & 3, Entertainment and Utility rooms) plus every other wall posts everywhere in range from the hallways, also doing the smaller rooms (toilet, tech and knick-knack cupboards etc) plus the front door and stairs too. We want to be able to place our laser line generator in each room separately and get the floor height exactly the same all over the house when we get to do that room.

One of the first things we needed to do, after doing the laser calibrations, was to empty the content out of each room we want to work on, so in Bedroom 3 we had to move our solar water tubes and a heap of ladders etc. so we decided to move them, the solar tubes to our new storage area, mainly the first floor and its great expanse, to get them out of the way for the time being. But first, we felt the need to be a bit careful and clever, to position these items upstairs so they don’t impact too greatly on us working upstairs like building walls etc. To this aim, we marked out an outline of each room and their walls, these being the Creative room, the Study, the Workshop and the toilet plus all the “triangular voids” spaces and the large storage space behind the toilet over the top of the back rooms of the house.

First-floor-rooms-marked-out-1

First-floor-rooms-marked-out-2

Then, we moved the six crates that holds our one hundred solar glass collector tubes from Bedroom 3 to upstairs and placed in the Study over the Entertainment room and front door. The heap of ladders etc. were moved to sit underneath the new staircase.
This meant that we could and did get on in constructing the flooring for Bedroom 3 (the one next to the Utility Room) and got the laser to shine a green line right around the room, aligned to the reference marks at the doorway and carefully marked all the vertical posts and stuck masking tape on the black plastic to see the mark there too. Then slicing five lengths of our usual 63mm CLS timber, we nailed up a perimeter of a support framework that will hold the 22mm thick floorboards when we are ready for them to go down. The room is arranged in a grid pattern with 600mm spacing between the contiguous joists and an alternating noggings in every 1200mm in the opposite direction.

We built a little laser hanger gadget that hooks on to the perimeter rail so the green light will be exactly the height of all the legs supporting all the joists and noggings. We cannot just simply measure the distance from the concrete floor surface, up to the underside of the CLS joist because both the concrete floor and the wood slowly rises and dips in random directions, hence this little clever hanging gadget to position the laser line generator to shine its green line against each set of legs to be trimmed.

Laser-marking-leg-heights-1

We are using our left-over treated timber for our legs, plus dipping the cut ends into more preservative treatment, all to protect the wood from rot if we ever got a flood under our floor, we don’t want to find that our flooring supports started rotting after a decade or two and find our floor sagging. So we are dipping the cut ends into a trug that has black died preservative and therefore we would know which end to put downwards.
But these little legs are only 63mm wide (by 38mm in the other dimension) so aligning the leg underneath the horizontal joist (which is also 38mm thick) would poke out only by 25mm. This is plenty enough to support noggings but only on one side at a time. This means that we staggered the noggings in each row so the whole room is evenly supported across the floor.

Bedroom3-Floor-supports-in-place

The next job was to sort out the bundle of water pipes and cable conduits that runs across the room, from the external walls, from underground and passing through from the Utility room. We did the hot water pipes first which comes along from the Utility in 28mm pipes and curves towards the en-suite. We had always planned to have 28mm diameter pipes, to hold a high volume of water flowing throughout the house and also we wanted to constantly keep this hot water supply hot and active, ready for any demands. This means that we have two hot water pipes running alongside each other, a “flow” and a “return”, just like in a traditional central heating systems. But we recognised that there could be a good deal of heat loss, and money, in a constantly circulating system, losing energy around the loop all the time. So to this issue, we put down two layers of 100mm thick PU foam boards, sitting on the concrete and cut a slot in the top of the second layer for the 28mm pipe to sit snugly in.

Bedroom-3-Hot-water-pipes-layed-in-insulation

Then a 90mm thick “lid” went over the top that brings it up to the underside of the wooden floor supporting framework. The rest of the space on either side will also be filled in with more insulation so this hot water system will be as protected as possible against heat loss and provide our whole house with quick supply of hot water when we want it.

The cold water is also supplied in a 28mm diameter pipe but that is running “loose” nearby the hot insulated pipes and all three are routed to arrive just outside the en-suite doorway where we will have a liftable panel cover to gain access to the various controls and devices to condition and supply the water needs for the basin and shower in the en-suite. We built an extra framework around this area to support the “lid” and also inserted vertical PU foam boards to act as a barrier to keep the loose insulation in the rest of the room from “leaking” into our inspection and servicing chamber.

Then we connected up more water pipes, this time in 15mm diameter pipes that connects to our Energy Module (a buried tank of water), a pair of them so we can exchange the energy (hot water) from the tank to the Utility room and back again. the pair goes into conduits that were fitted to provide a “high” and “low” extracting points so we can draw off the floating hot water and put in new hot water down in the bottom of the tank. These 15mm pipes are only intermittently used so they don’t need a great deal of insulation, just the normal floor insulation to keep it warm while it is being transferred to and from the Utility room. The other 15mm pipe going into the Utility room is a connection to our Swimming lane. We did an external connection (drilling through the concrete wall) several months ago and so we laid in this pipe too. This Swimming lane connection will provide a source of cold water to help “sink” any excess heat away. The Swimming lane is a 25,000 litres of reasonably cold water to make use of!

The final 15mm water pipe is also an external connection but this time, it is a low-volume irrigation watering system to serve the garden in and around the this end of the house and this 15mm pipe only needs to travel to our servicing chamber we have already made. At this point, a computer controlled water valve will be installed and connected to our cold water supply later on when we have designed and built such devices. The other connections to our servicing chamber are empty conduits, the first two being also irrigating watering feeds but this time up to the Eves for any hanging baskets etc. The final five other conduits snaking across the room are the temperature probes that will monitor the regions immediately surrounding our buried Energy module. All these conduits are 20mm diameter black polyethene pipes and we joined them to the sticking (out of the concrete) up portions using short length of the fatter 25mm polyethene pipe which fits perfectly and very tightly providing a smooth joint and transition for our cables and sensors when we push them down the conduits.

Bedroom3-Plumbing-access-area

Bedroom-3-Conduits-in-floor

We are not quite ready to put on the lid or fill the space with the insulation rubbish because we got other tubes to lay in the floor, this time for the air supply. We are going to have four 50mm conduits running from the hallway, next to the doorway, and branching out to the four walls, to distribute the fresh air. We will have a air channel just at the bottom of the walls to spread the air out and enter into the room itself in a gentle flow, without too much disturbance to the feel of the room. We won’t be able to totally avoid any movement as it is meant to be providing fresh air and drawing the old stale air out at the ceiling, just like as if the windows are open on a warm day. Another set of conduits are needed to be laid in, this time to route the electricity cables from one side of the utility channel to the other side, going around doorways and windows. This will be done when our delivery of new twin wall plastic tubing arrives next week.
In the meantime, we started on the task of nailing up the horizontal wooden rails, we called these utility rails because their function in life is to provide the space for our Utility Channel that goes around the whole room at the 800mm to 900mm height, plus also we are using this separation to allow for the air channel to run around the room too, down near the floor. Each of these horizontal CLS rails (our usual 63mm by 38mm timber) are positioned as follows:
- 235mm off the floor (air channel)
- 772mm (bottom boundary of utility channel)
- 1010mm (top boundary of utility channel)
- 1703mm (mid support point for wall board)
- 2422mm (support of wall boards at top of wall)
These measurements are for the top edge of the CLS timber because we can see it with our green laser light (more later on) and a 22mm offset is also added because we are measuring from the floorboard supporting framework that will have the 22mm thick floorboards laid down later on. We marked the door post with these measurements and then clamp our green laser line generator which is sitting on a small shelf at each measured mark. Then we went around nailing up lots of CLS timber to create the wall framework for holding up the finishing surfaces and of course to provide the space for our electrical sockets etc.
We started using our left-over timber (a large pile of it in the kitchen) to form these horizontal rails by using a biscuit joint to join smaller lengths together. We also inserted a horizontal rail at the window seat level, this one being 500mm off the floor surface.

Aligning-a-rail-to-the-laser

The-laser-bracket-clamped-to-the-wall

First-three-rails-fixed

That concludes the work so far for this week and we will carry on next week with the wall support and laying in more conduits when they arrive.
24 July 2021
Staircase Designed, Parts Created and Fully Assembled

We started on our next task on Wednesday, to design, create the parts and then build the staircase, all in just four days!
The first job was to get our two remaining pieces of the LVL timber, some 6metres long and sliced a shallow angled cut at the beginning of both planks. This end will be sitting on the concrete on the ground floor and rise up towards the first floor, at an angle of 36degrees. At 4936mm along up the bottom edge from the concrete, we then cut a triangle birds mouth where it will hook on to the first floor and its floorboards, so that the top step will exactly be the same level of the flooring when we get around to building the rest of the flooring layers and carpet etc. These two very long elements are called Stringers. Everything will be mounted to these stringers hence why these pieces of timber are 240mm wide, 45mm thick and laminated like plywood to make a very strong structural framework for the whole stairs.

Ply-wood-for-the-stairs-1

Ply-wood-for-the-stairs-2

The rest of the day was spent in taking four sheets of our newly purchased high grade 18mm hardwood plywood, with 13 layers and good quality veneers and sliced it up into a series of strips, four long strips of 205mm wide and 2.44metres long, then sliced the remainders into exactly 950mm wide. We used our big saw mounted into our workbench. The next set of cuts was done to the 950mm wide pieces to make sixteen 300mm deep planks, these being the “treads” of the stairs and followed by fourteen 225mm high pieces, these being the “risers”. Using various left-over pieces, we made sixteen narrow 27mm wide strips and then glued each one to each Tread piece thus making a thicker edge to each step, deliberately overlapping the front edge so we can trim off the excess and the dried glue to make a smooth finish.

The following day, Thursday, we took our four narrow strips and paired them up and proceeded to mark along one edge exact measured marks, taking from a spreadsheet printout showing the calculated distances from each step to the next one. Then using a right angle framing square, we precisely positioned a diagonal piece of straight wood and clamped it to the framing square so that first side was 270mm long and the second side was 195.4mm. This jig was aligned and slid along the edge of our paired strips to every previously marked positions, to draw the right angle triangle down on the plywood, to which we positioned our next piece of equipment, the track saw to carefully cut out each of these triangles, to end up with a long series of pointed staircase like steps. These four prepared sawtooth like strips were then glued and and nailed to our stringers that will form the basic structure to hold the treads and risers that will form the whole staircase.

Stringers-with-tread-supports-glued-on

The rest of the afternoon was spent setting up the router machine and fence to guide through the 16 treads and 14 risers. The first little job was to use the straight cutter with a top ball bearing, to run all the treads that had the extra bit glued on and cleaned off the dried glue and excess material to make a smooth flat edge ready for the bullnose. The last bit of the day was setting up a 18mm wide straight cutter and position the fence so we can slice a 5mm deep slot for the riser to fit into on the underside of the tread, just behind the bullnose, exactly 25mm in from the front edge and proceeded to get that done.
On the Friday, we carried on with the routing operations, this time, to cut a bullnose on the tread front edge. We did some test pieces with different radius cutters doing a 9mm, 12mm or 18mm radii. The thickness of the front edge is now 36mm (double layers of 18mm plywood) and we found that the 9mm radius was too small and the 18mm is too large so we settled on the 12mm. so the 16 pieces were sent through the router on both sides to generate our bullnose.
In the meantime, the LVL stringers were cleaned up to remove the excess glue that has bubbled out from the step support plywood

Glue-exuding-from-plywood-joints

The last task for the treads were to drill clearance holes along the front edge in the middle of the slot (to join and tighten onto the riser piece) and two more clearance holes on both left and right hand sides to fix the tread down. That finished all the preparation tasks to the 16 Treads.

For the 14 Risers, first we aligned them all together into one neat pile and clamped them all together, making sure they are all squared up. Then we sliced a small notch out of the bottom corners, some 20mm wide and 25mm deep. This notch will allow the risers to fit down below the Tread level and allow a slot to be positioned 25mm from the bottom edge that will support the back of the tread piece. Talking about this slot, that is our next job, setting up the router this time to cut a similar 18mm wide slot and 5mm deep (just like the other slot underneath the tread) but cut horizontally near the bottom of the riser, as mentioned before, 25mm off the bottom edge. Finally, five more clearance holes was drilled along the slot to help draw in the tread and ensure a tight joint for the glue to work at its best performance. Oh yes, two more holes were done, one on each left and right side to secure the riser.

Stair-treads-and-risers

By the end of Friday, we had done some test fittings and there were concerns over the stringers not being straight and a little twisted and bowed and the tread and riser combination were not sitting in neat and square (It might be ‘engineered’ timber but it’s still only wood).
So on Saturday, we verified that our two stringers matched together (bringing them together and inspecting the support steps etc) and also confirmed that the a riser placed in the top most step position was right angle to the first floor stair hole itself. We also got out several large clamps and straps to squeeze together the two stringers together tight to a tread plus riser pair and all is actually looking ok after all. We left on a strap fully tight at the top of the staircase and decided that we would start at the bottom to fix each tread and riser pair in place, for real, using screws but no glue. We used the clamps for each pair to make sure everything is good and tight before screwing in the screws, but we did have to trim a tiny bit off the back edge of some treads to make everything fit snug in the two slots. We continued with this process, going up until we got over half way and decided that everything is coming together good and looking neat and smart so we felt that we could commit ourselves to permanently gluing everything together so we undid the screws out of the treads but left the screws in each riser to help hold the two stringers in alignment.

Stair-under-construction

So we proceeded from the beginning again and glued everything, fitted each step into place and applied all the screws this time, including the five screws in the back of each riser to anchor the tread into the slot. We only had to use the large clamp once or twice again as we went up and finally reach the top by the end of the day.

Looking-up-the-stairs

Looking-down-the-stairs

The-stair-body-completed

The-back-of-the-stairs

We have completed our steps for our staircase! We can now get up and down much easier, we can show our visitors our first floor without asking them to climb a ladder and also we can carry up larger and heavier items to get them out of the way while we are working on the ground floor. Yippee!

We will be adding hand rails and balusters later as part of installing the stair lift.

17 July 2021