Just been up in the lofts adding more insulation to the existing. Total depth is now about 220mm deep. Is there any point in adding more up to about 300mm?
I hate this job 
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Roof insulation depth - any point in adding more?
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Posted 7 months ago #
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Yes, definitely. 220mm is the minimum and another layer rolled out across in the opposite direction will make a big difference. I've got 3 layers now up to 500mm because the stuff was going so cheap last winter.
Horrible job though, I agree.
Posted 7 months ago # -
I've been using 100mm recycled polyester recently. It's about twice the price of glassfibre but much nicer to work with. I get it from Casto which is owned by Kingfisher so there's a good chance you'll find some in B&Q.
Posted 7 months ago # -
Absolutely. I had about 40cm in my loft, and I added another 40. It made a big difference to not only the warmth but also the noise from outside the house.
Posted 7 months ago # -
Yes + 1
I have 270mm in the barn: 100mm between the rafters then 170mm perpendicularly.
Posted 7 months ago # -
formerly an eco-building designer here, and I say YES.
It's the cheapest way you can improve the fuel efficiency of your home.
Just be sure not to block the ventilation holes under the eaves that allow air to circulate around the roof timbers.
AP
Posted 7 months ago # -
Yep, fill in between the joists and then go on top perpendicularly (if that makes sense)
Posted 7 months ago # -
Alex.. elaborate on that ventilation thing - I thought the purpose of the eave holes was to ventilate the entire loft, and I figured that since I have plenty of open spots I was ok. Are you saying that every rafter needs clear space around it?
Posted 7 months ago # -
you need to leave a reasonable air gap ( 100mm ?? ) where the roof comes down to meet eaves so that the air can get up through the eaves, through the gap and into the loft space.
i.e. dont cram it right down into the corners
Posted 7 months ago # -
also have been doing my loft, should i avoid putting my insulation rolls over electric wires??
Posted 7 months ago # -
no problem in insulating over wires. fill yer boots (or your loft in this case)
if you have less than 300mm you might find you can get subsidised to get it up to standard. local authorities have the funding - you just have to ask for it.
Posted 7 months ago # -
I have some GU4/MR11 downlighters recessed into the bathroom ceiling. At the moment, there is no insulation over them. What's the best way of dealing with this? Some sort of box/cover in the loft and then insulate over the while lot??
Posted 7 months ago # -
Yes..
Posted 7 months ago # -
Was up in a pals attic tonight and noticed the same thing as Druidh mentioned.
The attic was recently reinsulated and has the certificate pinned to a rafter. But.....the downlighters have no covers/boxes whatsoever.
Know from the "Holmes on Homes" programme (Canadian) that a cover should be used.
Any suggestions for a UK supplier ?Posted 7 months ago # -
You should be able to find metal light caps in any electrical wholesaler cheap, cover them with those and then you can insulate round. I have always left a small breather hole above all our downlighters as recommended by our builder. They do get really quite hot.
Posted 7 months ago # -
Posted 7 months ago #
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Clay flowerpots can also be used as covers
Posted 7 months ago # -
theres a bit of confusion in here as to what fire hoods do.
Generally speaking they are sold to maintain the fire integrity of the ceiling/floor.
They can be used to protect joists that are close to halogen down lighters, but oddly not necessary.
With LED down lighters they're not necessary at all.
Rock wool insulation wont combust from a downlighter.
As far as I can find out though, none of that is documented in the regs. Its a bit of a black hole.
Posted 7 months ago # -
those ones aren't fire hoods, they just stop the insulation from lying really close to the light fittings. They offer some air circulation and should assist to prevent (or reduce) any associated equipment from being damaged from the heat build up say transformers or where some people have just used open connector block with twin and earth cables really close to the lamp.
Fire hoods "should" form a seal if there is a fire from below, creating a seal between the room and the floor above and providing a fire barrier.
Posted 7 months ago # -
I was going to ask this the other day, as I have 5 rolls of insulation, and a well insulated house, might as well chuck it in then! Good times, keeping bills down, being eco and freeing up some space in the basement!
Posted 7 months ago # -
Oh well..... more crawling around in the loft then
Did I mention I hate putting insulation in??
Posted 7 months ago # -
Slight hijack - I'm planning to add another 200mm to my current 150mm.
It's slightly cheaper to go for 2 x 100mm rather than 1 x 200mm. Any real world differences? I wondered if the 2 x 100mm runs crossed over at 90 degrees would provide better insulation?
Posted 7 months ago # -
sharkbait - get yourself a paper suit to do it in. Tape the cuffs up. Get a disposable face mask while youre in the shop too.
Posted 7 months ago # -
By having 2X100mm you can lay each roll at 90º therefore reducing draughts and air flow. How significant this is, I don't know.
http://www.theyellowhouse.org.uk/themes/insula.html#in6Posted 7 months ago # -
I have some GU4/MR11 downlighters recessed into the bathroom ceiling.
Have you changed them to LEDs yet? Big reduction in consumption if you haven't.
Posted 7 months ago # -
Tape the cuffs up
Yes I'll do this next time as my forearms where proper itchy after yesterdays installation. Got the suit already so that's something. The worst lofts are the ones with no headroom so I have to crawl around - we've got two of thosebustardslofts.
Changing our halogen downlighters is another thing I'd like to do as we've got about 45 in the house
Posted 7 months ago # -
The price of the good GU10 LED replacements is coming down still.
I have about 100 of them in the barn and before buying that many bought about a dozen or so as testers to work out which ones to commit too as you can never be sure of beam angle, or colour temp until you have one to test.
The most expensive ones I got were about £20, the cheapest were £3.50
about 3/70 £3.50 ones have failed.
None of the (20 or so) expensive ones have.Posted 7 months ago # -
Before you add extra insulation look at the build up of the existing. Then look up the requirements for ventilating cold roof spaces/underside of roofing felt.
Then make sure you understand interstitial condensation and how to avoid it (to be safe you may need to take out all your existing insulation and install a properly sealed vapour barrier directly over your ceiling before you put any extra insulation in).
If your electrical cabling the answer is it depends on its sizing, its loading, and how old it is.
Posted 7 months ago # -
The price of the good GU10 LED replacements is coming down still
when are they going to appear on dealextreme ??
Posted 7 months ago # -
sharkbait - Member
Oh well..... more crawling around in the loft then Did I mention I hate putting insulation in??I did a load at the weekend and it was a real chore. We've got a lot of boarding down & a very shallow pitched roof. I have added insulation mainly to the area that is too low to access anyway. Crouching for hours, going back and forth moving boxes, rolling out the insulation, shoving it into place while lifting cables etc. What a ball ache! But at least it's done. There is a large unused area of boarding at the end of the loft (we just don't need that much storage space) and I plan to cover that too, but couldn't face it last weekend. I was done in, so will do it another day.....
Stoner - any links to a site selling these LED GU10s?? We've got 3 in the kitchen & 6 in the bathroom & I'd be keen to change them. Any recommendations for colour temp/beam angle would be appreciated.
Posted 7 months ago # -
Joining the hijack, my kitchen has GU10s and they keep blowing after a few months (not all at once) will the LEDs last longer? Also should I get someone to look at the electrics?
Posted 7 months ago # -
Yes - the LED GU10s last a lot longer. Problem at the moment is that the brighter ones are very, very expensive, seem to have a limited spread of light (spot more than flood) and are often longer than a standard GU10 - so stick out from the light fitting.
Posted 7 months ago # -
Just realised how cheap the insulation currently is at B&Q, so plan to add some more insulation to my attic.
I noticed that there was no insulation under the cold water tank in the attic, should I insulate this area? The tank has a jacket, and is lived in all year round, would I run the risk of the tank freezing?Posted 7 months ago # -
As a DIY numpty, what do you do when you've got a partially boarded floor in the loft and want to keep it? I take it there's little point in lifting the boards and packing more under there as it will compress?
Posted 7 months ago # -
Compressed insulation is still insulation.
I put in a suspended floor with enough room underneath it for tons of insulation...
Posted 7 months ago #
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