SuperFoil at aldi and skillbuilder

[George Miles]

aldi are selling superfoil

it good?

See also Roger Bisby Skill Bu8ilder at

opinions and experience please...

George

[Theo]

It depends what you want it for.

Foil blocks radiated heat very well - this is why you get foil windscreen covers and spacecraft. However just a sheet of bacofoil would do that.

In terms of conduction, this SF6 has an R value of 0.99 ('core performance') and various bigger numbers 'including air spaces' (roof R=1.9, wall R=2.32, floor R=3.64), the exact conditions are unspecified. R-values are thermal resistance, like electrical resistance.

By contrast foil-backed Celotex GA4000 has the following R values:

50mm: R=2.25 75mm: R=3.40 100mm: R=4.30

So the superfoil is useful if all you have is a narrow space, but not so great in comparison to thicker celotex. And superfoil is quite pricey for what you get.

But at the end of the day no insulation is going to help you if air can flow past it. So different form factors can help in different scenarios.

Theo (this is interesting in respect of my celotex thread - admit I hadn't considered the superfoil behind plasterboard...)

[Theo]

The numbers I did for my roof calculations for the other thread:

I started off looking at aerogel products since they have the lowest conductivity per thickness, but then they have to be bonded with plasterboard.

Spacetherm 32.5mm = 20mm Aerogel + 12.5 PB R(plasterboard) = 0.125/0.19 = 0.066 R(aerogel) = 0.02/0.015 = 1.33 Total R = 1.4

Spacetherm 17.5mm = 5mm aerogel + 12.5 R = 0.4

Celotex 37.5mm = 25mm PIR + 12.5 PB R = 1.2

Celotex 27.5mm = 15mm PIR + 12.5PB R = 0.7

Thermaline 22mm = 12.5mm EPS + 9mm PB: R = 0.35

Spacetherm Multi:

6mm MgO PB + 10 / 15 /20mm aerogel R(plasterboard) = 0.006/0.19 = 0.0315 R(10mm aerogel) = 0.01/0.015 = 0.66 R = 0.7

15mm aerogel + 6mmMgO R = 1.03

20mm aerogel + 6mm MgO R = 1.33

PIR foam (celotex) without plasterboard

40mm R = 1.8 30mm R = 1.36 20mm R = 0.9

Pavatex Reveal Board (wood fibre)

30mm: R = 0.65 40mm: R = 0.90

Wediboard (XPS laminate)

20mm R = 0.15 30mm R = 0.8 40mm R = 1.086

27mm R = 0.58

So, given the SF6 superfoil is 30mm thick, if we believe the numbers for a roof it's R=1.9, and that compares with 30mm of PIR at R=1.36. And the PIR gives a smooth surface while the superfoil would need a plasterboard or ply surface to make it flat. If we only take the core numbers, the superfoil has an R=0.99 so not as good.

On the other hand the superfoil can be useful if you need a flexible product rather than a board, eg for fitting between timbers.

Theo

[ARW]

Big snip - sorry pal.

I did find these two sites in case it helps either of you.

But that says it is 25mm thick. And "This DIY product is made using the same high-quality materials as the fully certified Trade equivalent but will not have the extra 3rd party certification. This helps to keep the price low and the target market will not require this extra level of certification."

However

says it is 30cm thick and gives some R values.

Both 12sqm packages weigh the same.

I might have missed something (just got in from work and I am knackered)

- like they are different products.

[The Natural Philosopher]

This allows inferior crap to be sold to gullible idiots

[Andrew]

when tacked to rafters and compressed by the plasterboard it has hardly any insulative properties at the point of compression.

There have been some interesting 'arguments' between its makers and the people who make PIR rigid board insulation regarding the way it has been tested for performance.

It is more suited to houses in Southern Europe where keeping radiant heat out is more important than keeping heat in.

Only of use if it is imperative not to lose any headroom.

[Maksim Fetisov]

вторник, 11 января 2022 г. в 20:40:10 UTC+2, Andrew: