cliftyhanger
|
| posted on 8/12/12 at 07:59 AM |
|
|
insulating a loft
As we are about to exchange on a house, and the survey did mention the loft insulation was thin (understatement!) one of the first jobs, between
getting the new garage built of course, is to get some good insulation in there.
A bit out of touch, current house has a loft conversion so cellotex in the rafters. No conversion is planned, so I guess 200mm of rockwool?
Which leads me on to boarding it after. What is the perceived wisdom about "making up" the rafters? 4x2 screwed on to of existing? or how
about at 90degrees and use 2 layers of 100mm insulation at right angles? or I have seen loft legs???
And talking of lofts, any issues with raising the cold water tank up into the ridge and popping a coffin tank in? Give a bit more pressure to the
bathroom?
Hmm all this may distract me from what I really ought to be doing
Oh, and anybody know if the "free insulation" deals are still available to normal taxpayers? seems you have to be a benefit claimant to
get it now
Cheers
Clive
|
|
|
|
|
Peteff
|
| posted on 8/12/12 at 08:32 AM |
|
|
Contact your gas supplier when you move in and they will insulate your loft to current specification free of charge. I just did ours a week before I
received the letter but a friend across the street has just had his done.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
snapper
|
| posted on 8/12/12 at 09:11 AM |
|
|
Just raise the rafters with wood in the same direction to make it easy for the gas company then board over
Don,t forget the hatch and use fire covers over any recessed lights.
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
|
|
|
Charlie_Zetec
|
| posted on 8/12/12 at 09:34 AM |
|
|
All as above. When I bought my house 3 years ago, the only lofy insulation was a 20mm thick bit of polystyrene and some newspaper!
We called the energy provider, and essentially purchased rolls of rockwool for £1.50 a roll and set about insulating the loft. I think for rockwool
only they recommend 250mm thick (rolls of 100mm and 150mm thick material). We laid the 150mm down in between the joysts and it fitted nicely, then
just rolled the extra material straight over the beams on top at the sides of the house. All downlighters were boxed to avoid fire hazard! The
centre section of the loft and hatch area was boarded over and I put a bit of old carpet on it, which acts as additional insulation as well.
When I get the roof re-tiled & underlayed next spring, I might get some celotex board and put it in between the roof joysts, and then remove the
additional rockwool over the floor beams so I can board the whole lot out....
Artificial intelligence is no match for natural stupidity!
|
|
|
YQUSTA
|
| posted on 8/12/12 at 10:00 AM |
|
|
Be quick with your getting it done as the rules are changing (according to the guy who came round about my wall insulation)
The gist of the changes are that when you buy a new house you will be able to claim for all the work to be done from windows to solar panels and all
in between. it is complicated to explain but sounds like a good idea.
Worth checking when this will come into play but the guy told me they were rushing the orders through so they could keep the work coming in.
"If in doubt flat out"
Colin McRae
|
|
|
fishywick
|
| posted on 8/12/12 at 10:02 AM |
|
|
All the above +
I'm not sure if you have muddled your rafters and joists. Generally the loft is ventilated to preserve the timbers, hence it is largely a waste
of time insulating the rafters unless the void loft area forms part of the thermal envelope of the house ie. a loft type conversion.
Secondly on the same theme, don't block the eaves ventilation with excessive loft insulation.
Loft insulation boards are also available, ie. insulation sheets that will take some weight. I think B and Q do them although it may well work out
cheaper to cross the joists with 4 x 2 as you suggested.
Energy Saving Trust have lists of who will do it for free, although the CERT scheme is supposed to end this year, may have been extended?
|
|
|
rgrs
|
| posted on 8/12/12 at 10:06 AM |
|
|
Currently the idea is 270mm in two layers at 90 degrees to each other.
However as this is existing you can do what you want. Insulation available from your energy supplier is available at maximimum discount. Insulation
bought at DIY shops is also discounted and therfore cannot be used in new build.
Insulation available from builders merchants is not discounted and can therefore be used in new build.
However in your case i would be inclined to find a supplier of PIR board (celotex etc) and ask them for damaged sheets as they are a fraction of the
cost, then put 100mm over the top.
The Pir board is far more thermally efficient but it's acoustic properties are not as good as say rockwall.
You get the best of both worlds and provided your joists are deep enough you might not have to raise the floor.
Roger
|
|
|
loggyboy
|
| posted on 8/12/12 at 10:17 AM |
|
|
Current building regulations is generally 300 or 400mm. Obvioussly yout dont have to comply with that, but that gives you an idea of whats expected in
a new build house.
As you say, laid in perpedicular directions is best.
I think its a little more expensive but a good option is Ecowool, its recycled, and beacuse its not glass fibre you wont have to where gloves to
install or everytime you want to move it to access something in the future.
Most deals for free/cheap insulation grant have ended now.
Mistral Motorsport
|
|
|
cliftyhanger
|
| posted on 8/12/12 at 02:42 PM |
|
|
yep, the deals seem to have gone just as we actually need them. Also noticed the cost of insulation has rocketed recently (wickes were £7 or so a
roll, now £25!)
Will investigate the cellotex route, could lay on top of the joists (yes, I did say joists earlier, it referred to the loft conversion where it is put
between rafters, new place will be insulated between/over the ceiling joists) and then board directly on top. Will be easier/quicker and by the time I
allow for increasing joist depth may not be much different in price.
May find a deal, may have to pay.....
|
|
|
JoelP
|
| posted on 8/12/12 at 05:52 PM |
|
|
several years ago i did my loft out by putting 100mm between existing, then 4x2s at 90 degrees, with another 100mm between that. 21mm chipboard over
the top, then a good layer of junk. It has worked insofar as the loft is fooking freezing now, but the weight of it all has caused the ceiling below
to sag badly - i mean its about 40mm down in the middle of the room. It was a 6m span.
Looking back, it needed 6x2s parallel to the exisiting, sat on the walls at either end. Additional insulation via 35mm kingspan over the joists and
under the boards - im confident the kingspan would not crush under the low loads up there.
The only solution now seems to be to put ra large timber across the room to support the middle of the span.
Beware! Bourettes is binfectious.
|
|
|
coozer
|
| posted on 8/12/12 at 07:37 PM |
|
|
I have been thinking of this for my new house (once I sell this one)
So my thinking is to bond a 4" layer of Kingspan to the UNDERSIDE of the ceiling, then with some long screws fasten battens underneath and get
some dudes in to board and skim that.
Any thoughts on that??
The loft conversion in my current house is done out with 4" Kingspan and we do not ever have the rads on upstairs.
1972 V8 Jago
1980 Z750
|
|
|
JoelP
|
| posted on 8/12/12 at 08:39 PM |
|
|
No need to baton the kingspan in that circumstance, the drywall screws would grip the kingspan well enough to hold up a plaster board. Or, use foam
backed boards.
Beware! Bourettes is binfectious.
|
|
|
skodaman
|
| posted on 8/12/12 at 10:08 PM |
|
|
I recently got told by the council that some flats I rent out needed 300mm insulation. They gave me six months to do it and came back to check as
well. You can get one layer of 150mm inbetween the joists then go across the other way with another 150mm layer.Kind of messes up putting a floor in
which is what I do in the properties I live in just to store locost bits.
Skodaman
|
|
|
SteveWalker
|
| posted on 8/12/12 at 11:13 PM |
|
|
quote:
Originally posted by cliftyhanger
And talking of lofts, any issues with raising the cold water tank up into the ridge and popping a coffin tank in? Give a bit more pressure to the
bathroom?
Normally your tank sits on a board laid on top of the ceiling joists and there is no insulation below the board. If you raise your tank up into the
ridge, you may find that the lack of heat from below leads to freezing. You could box the whole thing in, right down to ceiling level, so it remains
heated from below. Or add a small heater and thermostat, so it is never allowed to freeze. Or keep the existing tank and add a shower pump.
SteveW
|
|
|
