Insulation: Multilayer foils vs Celotex

[DoubleSix]

Hi chaps,

It's that time of year, my attic conversion is old school and freezing.

A trade friend mentioned multilayer Superfoil SF60 with an R value of 4.63 as an alternative to Celotex etc

This has a lot of appeal in terms of fitting as I can just bang it up under the rafters instead of sawing and taping bits of Celotex which is a tedious job.

So, anyone used this stuff? Thoughts?

[DoubleSix]

Space isnt an issue. I was going to batten out the inside of the rafters and staple the multilayer foil, taping the joints. It's just attic space/storage at the moment.

Thought it would be an easy install...

So is multilayer foil snake oil or not?

[DoubleSix]

Ok, so given the Superfoil SF60 product im looking at is 100mm thick (not that thin) am I right in thinking this an easy install alternative to Celotex, Kingspan et al?....

http://www.just-insulation.com/002-brands/superfoi...

[DoubleSix]

Not sure people are taking the time to look at the product before commenting.

This product is 100mm thick!

[DoubleSix]

andy43 said:

How do you fix it if it's 100mm thick? Staples won't work as they'll compress it to nothing. And how do you join it - tape won't work as it's presumably multiple layers of foil/bubble wrap.
Reflectivity and airtightness when installed right are positives, but the fact that some BC depts don't like it speaks volumes imho.

Well, that was type of discussion I was hoping to get into!

I called the manufacturer and they state it compresses to 20mm where it is stapled (around the edge). I don't think there's any issue with taping together as the outer sheets are heavy duty foil. There are around forty layers, no bubbles that I'm aware of...

The chap above mentions £10 a metre which again shows people have other products in mind - the stuff i have linked to above is not cheap!! Around £180 a roll. Maybe why BCs dont like it?

An expensive but easier to work with solution??

[DoubleSix]

TA14 said:

Why not just run it across the lower edge of the rafters, stapling in the middle of each rafter? That would be quick, easy and effective for a storage area.

Yeah could. But a lot of strain on a few staples then. Battens would allow staples every 20cms as recommended.

But tbh I started the topic as I'm interested in the efficacy of the product itself, installation not really an issue.

So far, only anecdotal or 'reckoning' has been put forward as a reason not to use it which isn't enough for me to dismiss what appears to be a good product. Especially when most seem to be refering to the thin stuff that makes big claims....

I am disappoint.

[DoubleSix]

TA14 said:

To be fair to the PH commumity I thought that this was quite a good post

Little Lofty said:

I used it on a couple of lofts a fews back. There was a big debate going on about its claimed u values so LABC stopped us using it for a while. I quite liked it, it wasnt cheaper but saved loads of time and mess, it takes up far less storage ( try getting 20 8x4 sheets in a loft) and is much nicer to work with, celotex dust is not nice stuff. We did go back to using 2 layers of Celotex as most of the building inspectors prefered that method, but it does have its uses.

Absoultely. I'm hanging on to it as an example of real world experience and someone who understood the OP.

Cheers Lofty!

[DoubleSix]

Hi Lofty,

Here's a spec sheet;

http://www.just-insulation.com/002-brands/superfoi...

100mm is stated, guess it's a premium version. I figure it takes same amount of time to fit so might as well go for the best - also on promo at online retailer right now.

Any further thoughts?

[DoubleSix]

037 said:

I didn't look at the product before commenting! I use Tri ISO super 10 which is around 30mm thick. I can only comment that I think it's a great product.
I'll not offer any advise as you sound like you know it all already.
I'm out!

Apologies if it came across like that, just feel like I've going round in circles on this one!