We are making steady progress on filling our roof rafters up with the first load of PU foam insulation boards.
We have now completed the I section, the H section, the G and F porch section as well as finishing off section E. Together with the previous sections D, C and B. We have used about half the quantity of the foam bits and pieces we bought and we still have a fair number of pieces upstairs, waiting to be used up.
We estimate that we have completed just short of half way. So, it will be a race to whether we will have enough to complete the job when we get to the Great Room. This is not really a problem because we had originally designed for our roof rafters, which are 400mm deep, to have glass wool put in. This would give us an U factor of 0.1W per square metre per °C difference. For much of our roof, we will be even better than that, coming in at around 0.075 W in some spots.
To give you some idea of what that means, our roof is about 300 square metres in total so if you multiply those two numbers together, you would get about 25W of heat loss through our roof for 1 degree difference. So if we run our house at 25°C, nice and cosy, and the chilly outside is hovering around 5°C, then there would be a difference of 20°C so multiply that number with the other number we got .. 25W times 20°C will give 500W of heat loss for the entire roof area of our house, on that chilly day! One small fan heater on low power would be enough to keep us warm!! 
So we now need to build a shredding machine to reduce the rubbish to small lumps, ready to be poured under our floorboards in our Great Room.
So read our next blog for a report on building another quick’n’easy piece of DIY equipment!!
We have now completed the I section, the H section, the G and F porch section as well as finishing off section E. Together with the previous sections D, C and B. We have used about half the quantity of the foam bits and pieces we bought and we still have a fair number of pieces upstairs, waiting to be used up.
We estimate that we have completed just short of half way. So, it will be a race to whether we will have enough to complete the job when we get to the Great Room. This is not really a problem because we had originally designed for our roof rafters, which are 400mm deep, to have glass wool put in. This would give us an U factor of 0.1W per square metre per °C difference. For much of our roof, we will be even better than that, coming in at around 0.075 W in some spots.
To give you some idea of what that means, our roof is about 300 square metres in total so if you multiply those two numbers together, you would get about 25W of heat loss through our roof for 1 degree difference. So if we run our house at 25°C, nice and cosy, and the chilly outside is hovering around 5°C, then there would be a difference of 20°C so multiply that number with the other number we got .. 25W times 20°C will give 500W of heat loss for the entire roof area of our house, on that chilly day! One small fan heater on low power would be enough to keep us warm!!
We have reached a point where we need to tidy up the large rubbish pile that we have created (as well as 2 bags of bits accumulated over the last year)
So we now need to build a shredding machine to reduce the rubbish to small lumps, ready to be poured under our floorboards in our Great Room.
So read our next blog for a report on building another quick’n’easy piece of DIY equipment!!