Loft insulation, polybeads?

[Donwill]

Due to the low angle of my roof I cannot get into all parts of the main roof-space in fact part of the roof space was totally inaccessible until I put in a small roof access trapdoor. Due to my general decrepidness I cannot crawl through this 15" square aperture with limited headroom to lay fibre insulation and I wondered about using polybeads and blowing them in there. Can I hire the blower kit and buy bags of the stuff? any advice please? fire risks? etc Don

[JimK]

what about them blowing around after you've done it? someone on here (I think) described having "snow" blizzards every time the trap door was opened...i.e. Right PITA

fire - yes they would be flammable (unless you can get some treated ones?) and would be *bad* news if the fire started up there... but if fire started below in rest of house you'd probly be outside (or dead) by the time they caught light...

Cheers JimK

[Dave Liquorice]

I though Vermeculite (sp?) was the normal sort of lumpy loft insulation. I wonder about blowing it in though, I don't think you have much control on where it landed. All right in a cavity wall where it's contained but in the more open space of a roof void?

[Timothy Murphy]

I have exactly the same problem, with senility added to decrepidness. An insulation-laying robot would be the perfect solution.

[<me9]

Are we still allowed to borrow a small child? I used to get my sister's youngest to poke wires up from under the floor. There's no way he'd fit now though.

[Andy Dingley]

Not something I'd ever use again (just used 600 l of the two to make the drainage layer under my green roof). There's naff all difference in function between Perlite & Vermiculite, but Perlite is far nicer to have to work with.

[Stuart Noble]

Coarse vermiculite was £8.80 per 100L lat time I bought some. Nobody locally was stocking Perlite, and the online price was at least double that IIRC.

[Andy Dingley]

I've just paid a tenner for either, same price. Local retail is twenty.

[brass monkey]

I'd personally turn up the heating before i'd even contemplate using this crap. After a few windy months it'll look as though someone has been trying to build a slalom course. Some areas are bare, others are about 2 feet deep.

*My* problem is getting rid of the friggin stuff. And yes, open the loft hatch and expect a snowfall.

Did I mention that I wasn't too keen?

[js.b1]

Loose stuff will be "re-arranged" in any loft due to the wind.

- In so doing you may end up blocking eaves ventilation

- Never mind ending up with "none" in places

Can you use rigid insulation - cut to size and just pushed in?

- There are various "seconds" suppliers of the stuff

- Not as cheap, but "it stays put" and works well

The problem with loose stuff is if any moisture builds up, its effectiveness diminishes not to mention mildew (obviously it should not, but I'm not convinced with virtually months of relentless rain).

Near my mother's a lot of houses got unbonded polybead for CWI - believe me it snows the damn stuff every winter, and if you use a core drill there is a chance of never being found again. All it would need is a slip with expanding foam and they would be burying a termite mound or leave you on the front lawn as a "modernist gnome feature". Aside: why don't they bring back the non-expanding foam they once did?

[JimK]

thought they had -in tins anyway?

JimK

[Stuart Noble]

Vermiculite is very good for the garden if you need to get rid of any. Not sure about polybeads, but I guess they would have similar properties.

[Andy Dingley]

Nope. The beads aren't porous (to a useful degree for horticulture). They have _some_ use for conditioning heavy clay soils in somewhere like South Bristol, but not so that you'd ever want them in a pot.

[Stuart Noble]

The strange thing about vermiculite, perlite, (and rockwool) is that they don't *absorb* water, they just suspend it within their structure, rather like a J cloth holds water without being porous. Splitting hairs maybe

[Andrew Gabriel]

Interesting. I think I still have half a large bag in the loft, left over from making the hearth floor. (Loose dry-ish mix with sand and cement to make a high temperature insulating layer).

Bought it from Travis Perkins about 8 years ago. Computer said they had 3 bags, but they had to turn the depot upside down to find them, and none of them had ever seen a bag of it before, and so didn't know what they were looking for.

[NT]

Other than rising to the top and blowing everywhere.

NT

[Stuart Noble]

Vermiculite holds so much water that it rarely dries out sufficiently to blow about. Certainly cuts down watering by a huge amount in summer.

[Stuart Noble]

I bought mine from a large distributor, and the fork lift had to move several pallets to get to the remaining stock. Something tells me it's not widely used these days other than perhaps for flue liners.

[Andy Dingley]

Try the chemical waste trade. They use huge amounts of it - any random junk in small bottles gets loaded into 40 gallon drums, packed around with vermiculite. It's unlikely to react with anything (unlike polystyrene or cellulose peanuts), it provides shock packing and it also absorbs spills.