DIY Attic Insulation - What is best?

Cork Skate

Just wondering what are the options for insulating an attic. I plan on doing it myself so i want to avoid using the fiberglass stuff if at all possible. Sheeps wool is an option but i have heard its fairly expensive when compared to what i'll actually save.

Are there any other materials which i can use? How do they compare on price? Can i put it in myself (is there anything i should be aware of)

fatchance

The rockwool or fiberglass is not that bad to install, a pair of overalls and a face mask is all you need. It's cheaper than other options and works just as well.

I did see hemp as an alternative, which was expensive but very friendly to work with and safe too, no need for gloves, masks etc.. and no you can't smoke it!

crosstownk

I insulated my attic with the fibreglass stuff about a year ago. What a horrible, horrible job. But the difference was noticable immediately. The house is now so much better at retaining heat.

JohnBoy

buy disposable overalls, get a decent face mask, i find there's ones for about 15 euro for sale in my local co-op shop for farmers, basically a high quality disposable mask, much more effective and comfortable than the cheap paper ones.

the paper ones will always leave a gap above the nose where air will come out blowing the odd stray fiber up towards your eyes.

buy optrex in advance

buy rubber gloves and masking tape, put on the overalls and then the gloves (marigold kitchen gloves are ideal for this) then tape the gloves to the sleeves of the overalls and go to work.

do it as soon as possible as it's much nicer to work in a freezing attic than a roasting one in the summer.

gears

Sheep Wool Insulation have a new attic insulation product called "Comfort" which is a good bit cheaper than it used to be, 40%-50% less I think. Might be the answer.

iandromiskin

Hi, me too. I'am about to redo my attic also, hopefully with a 4" layer between the joists followed by a 6" layer on top. I understand that the best way to cut the 4" stuff to fit between the joists is to use a saw or large knife ? Also does anyone know about the blue plastic you see in attics and how its used ? I was advised to cut it to shape and lay it between the joists and then lay the insulation above. Is this correct ????

Also, this may sound like a really stuped question, but which way up should the insulation go ??? I presume the smooth side is uppermost ?? Correct ???

Ian.

Saruman

Did you guys insulate an uninsulated attic? I mean my attic has fibreglass up there... probably 4" but i never mentioned... im just wondering are you talking about extra insulation? Or insulation from non insulated attic?
I would love to know how to find out where the heat goes in my house

iandromiskin

In may case, I'am insulating a new attic and increasing and improving the insulation in the main attic. There used to be a garage on my house, but when we bought it it had been converted into a playroom, now our dining room, but its permanently cold as there is no insulation above. So needless to say I have to insult that. The main attic does have insulation, but only one badly laid layer of 4". The middle portion where people stored stuff and access the tank is compacted and needs another layer too. But I also wanted to find out about the blue plastic trick as I'am told it prevents or blocks heat loos.

gears

I imagine this blue plastic trick, is used as some kind of vapour barrier. Personally I don't think this would be a good idea as any moisture would be traped between the ceiling plasterboard and the plastic.

Any more comments.

Mellor

It wouldn't be a vapour barrier, possibly a vapour control membrane.
This should be fitted before plasterboard, and i dont think cutting pieces for between joist would help at all. It is for moisture control, not for heat loss.

As for cutting fibreglass, what centres are your joists at. if he rolls are onlt slightly larger, you can compresses them into place so that they hold tight

hobie

A pair of disposable overalls (with hoodie) or old knitted hat (old codgers style) ..... gloves ..... old boots/shoes .... old socks .... gloves .... oh, and gogles and face mask

and throw the lot away when you have finished .....:rolleyes:

I already had either 4 or 6 inches between the joists (can't rem) and added a second layer of 6 inches on top (all fibreglass)

first thing I did was to fit a permanent lighting system ( 4, 100watt bulb/holders) and 3/4" plywood walkway (2 ft wide) from one end of the loft to the the other ....

for my second layer I purchased 4ft wide rolls and laid them uncut, across the joists/existing layer, with very little cutting required to suit the final overall width ...... a normal wood saw is ideal for cutting the rolls ( I did the cutting in the attic) ......

you only have to do it once and it's there for ever .....

well worth the effort .....

Cork Skate

Aahhh, i HATE that fiberglass stuff .... but everyone is saying go with that, d'oh !!

Cheers for the tips people, it a good point about doing it in the winter, it is actually roasting up there in the summer. The walk way is a good idea aswell. For the clothes, i might look into a space suit, i seriously hate that stuff.

Mind is made up, i'll start on it this weekend. Just one thing, i have got the 4' between the joists so it just the layer on top, should i pack them together tightly or just enough to stop a draft kinda thing.

A builders providers is the best place to buy it i suppose, B&Q, Woodies etc. cost a fortune.

pjq

When I looked at this last October , the cost of DIY fiberglass was +- €400- plus overalls etc. so I was happy to pay €600- to have rockwoll blown into the attic . I think that I needed 150m2 at 250mm ( 1970s stuff worn to nothing ) .

pjq
edit - I see your from Cork , can't remember the company name based in Dungarvan Co Waterford , quoted over phone when I had the measurements .

eamon234

There's stuff you can get that's covered in plastic you just roll it out no dust no itching it's great and also better than normal stuff as one side has a silvery type plastic which provides better insulation it's a little more expensive than the normal stuff but much handier they were doing a 3 for 2 offer in Homebase on it a few weeks ago I got a few to top up the crap job my builder did

gabbo is coming

It's called SpaceBlanket, and it's wrapped in plastic. You still need gloves and long sleeves (and I wore a mask, just in case). It comes in 150mm, 200mm and 250mm. Obviously, go for the 250mm. THe thicker the SpaceBlanket, the shorter the roll.

About E14 a roll, so 200 quid and you're laughing. Made a savage difference to the heat in my house.

B&Q sell it, as do HomeBase.

nosmo-king

Is this space blanked stuff on the go long and does it work and last. Sounds really handy. Have a bit to do myself (from scratch ) .
Any further info..
Tks

antoinolachtnai

What about rockwool? I thought rockwool was an alternative to fiberglass for this application? Much easier to handle, and I think there is some insulation advantage.

renedescartes

There is one issue that has not been mentioned and that is "reflective foil" When we speak about insulation, we generally do not consider radient heat. Rockwool/fibreglass does not insulate against radient heat transfer as far as I am aware. It has been found (a by product of the space program) that aluminium foil is very effective in reflecting heat that is radiated. So in the USA products have been developed that as they say there are used to wrap their houses with foil. This foil can be stapled to the rafters and has the effect of reflecting radiated heat within the house and reflecting solar heat from the outside. I wonder if the foil backed rolls from B&Q perform this function? Has anyone any info?
Michael

GreeBo

All the upstairs plasterboard ceilings in my house are foil backed, Im guessing for this very purpose.

Mellor

Actually the foile backing on plaster boards is a vapor check,
as for insulation, there are foil based products, but they need to be exposed or in a cavity to be any benefit. wouldn't work well if it was just lying on the ceiling, except to reflect back into the ceiling.

renedescartes

Hi Lads,
Not sure I agree with the last comments. This foil stuff comes from the space suits design.....huge temps in the sun and low temps in shade. In US foil is stapled to the joists and in effect reflects heat from within and without. Its new thinking I think.
cheers
Michael