Wot no preps? [/chad]

What changes can we make to our lives to deal with the economic and energy crises ahead? Have you already started making preparations? Got tips to share?

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bealers
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Joined: 12 May 2009, 22:55
Location: Shropshire / Wrexham borders

Post by bealers »

woodpecker wrote:Consider inviting colleagues along to help on the build, and learn. They can camp. Especially if it's not mid-winter.
Cool, are you offering? :)

Seriously we're full steam ahead with the planning app right now and I can't really allow myself to think we might actually pull this off until I get that letter from Shrops CC planning dept containing the magic word 'granted'.

After that point there will still be a lot of work such as building control signoff, service connection, felling, transport & stacking of timber before we're ready but after *that* point we'll be actively looking for help.
kenneal - lagger
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Post by kenneal - lagger »

If you're putting in loft insulation it's not worth going above 450mm of Rockwool or 300mm of Celotex or equivalent. That will give you a U-value of about 0.08 ( the Building Regs requirement of 270 gives a U-value of 0.20). To get the U-value down to 0.04 from the 0.08, which won't give a noticeable heat saving, you would have to add another 450, at least, of Rockwool i.e. double the thickness. It's the law of diminishing returns with a vengeance. If you can't get Rockwool one of the equivalents will do as long as the density is about 30kg/cu m.

When you insulate and draught proof your loft hatch fit a couple of latches to hold it down. Wind pressure can lift it otherwise.

When adding the loft insulation you need to ensure that you have a 50mm air path to the outside over the insulation at opposite sides of the roof. The best way of doing this is to add vent tiles into the roof just above the finished level of the insulation to give the equivalent opening to a 25mm continuous gap at soffit level. Cut holes in the felt and fit a collar of felt to stop any rainwater coming in through the hole and then you can fit the insulation tight to the felt inside. If you fit the vent tiles you can then shove insulation over the wall plate until it hits the wall insulation below. This will help reduce the cold bridge at this point. To do the job properly you really need to take off the soffit board and fill any gaps against the wall left where the rafters come through and keep the insulation rolls apart.

This level of insulation, as I said above, will leave a cold bridge at the wall plate, where the rafters and joists sit on the outside wall even if you have done the work at the end of the last paragraph. This could cause some problems with mould growth so sticking a triangular section wedge of Celotex or similar into the corner and fitting a bit of plasterboard over with prevent this problem.
Action is the antidote to despair - Joan Baez
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