Shed roof insulation help needed

[Jim Ferrous]

Hi, my tool shed is 12' x 10' and has a flat tin roof with a gentle slope. The roof has finally rusted out after 40 years and I'm planning on re-roofing it next weekend. I would like to put some insulation under the new tin as when the sun is beating down on it, the heat radiated down can be pretty intense. The way the shed was built there is only 3 beams holding the roof up so I will need to put chicken wire up to stop the insulation from sagging over time.

Ideally I would have liked to have used vapor-chek but because of the way the shed is built, I wouldnt be able to seal all the edges and I think I would have a problem with glass fibres. So I will most likely just use sarking. Will sarking make much of a difference in stopping the heat being radiated downwards? If I put two layers up, does that increase the usefulness of the product?

Any help or suggestions would be great appreciated.

[Dan]

First stop would be to check out the "similar threads" box at the bottom of the page. Then ask more questions.

[Barry_White]

Jim

Sarking will help to a certan extent but no where as good as insulation.

This might be a better option for your situation.

http://www.homebaseexpo.com.au/products/home/astro/


Another one might be 50mm polystyrene sheets. you can buy it up to 6 metres long x 1200mm wide. This can span about four metres unsupported except at each end.

http://www.rmax.com.au/corporate.htm

[Jim Ferrous]

Bazza, I'll give that mob a ring on Monday and cost that.

The sarking for my shed is only $48 or $83 for Vapor-chek, so if that stuff isn't exhorbitant it could be good.

Its a bummer I can't use the Vapor-chek, I just would forever worry about the fibres.

[Jim Ferrous]

I suppose simply, I should have just asked how effective actually is Sarking?

[Ozartisan]

Hi Jim
When I built my shed, I lined everything with Aircell.
Not only does it give pretty good thermal insulation because of the trapped air in the cells, but is also give reflective insulation bacause of its metallised lining on both sides.
My shed is 21m x 9m & 2.7m high at the gutter. Really can notice the difference in temp on a hot day - and no condensation dripping on those cold nights!
I bought mine at Bunnies about 12 months ago when they had a deal going.
Here is a link to the manufacturer website
http://www1.aircell.com.au/pages/rural.aspx
and a couple of pics of my installation...
The stuff is tough too - haven't had the chance to finish cladding for over 6 months - & the aircell has withstood all manner of weather to date!
In my mind - a great product --

No - I have nothing to do with the manufacturers or distributors - just reckon a good product deserves praise.
good luck with your shed
Peter

[Ozartisan]

OOPS - Should have checked Barry's link first - but at least you have 2 recommendations for the same product!

[inflex]

What's a typical cost for this aircell insulation system?

I've got a pair of 6x3m sheds that could really do with a bit of protection from the summer (admittingly they're quite old now, standard cheap tin/steel sheds).

Paul.

[inflex]

I forgot to also ask, Since these sheds only have 3 supports with 3m span between each, should I use lengths of 19 x 19 pine glued at 450~600mm intervals to the underside of the roof and then tack on the aircell or foil insulation?

I was thinking that by providing a bit of an airgap between the roof and the insulation would additionally help things keep cooler, especially if I installed a whirly-bird.

Paul.

[old_picker]

I am going to do the roof on my lil fella with foam board from foamex in bayswater [melb]. $70.00 = Enough to do the roof.
i chose 1200x1200x30mm but they will cut to whatever size you want.
Prolly not the best solution but easy to stick up there [glue or silicon] and foam is a pretty good insulator. Like thats what they use in refrigeration I think

Your shed is just a smidge bigger than mine and with a skillion roof foam is the way to go. Easy to cut, light and cheap. I am also gonna stick some more on the outside wall that gets all the sun. The inside of that wall is covered in things hanging up, shelving and machines. To line it inside would be a nightmare so i just mentioned in passing to swmbo that i would be "sticking white stuf on the outside of the shed soon" and she goes "yes dear" thus avoiding future complaints about the ongoing "That shed is a disgrace" discussion.

[inflex]

I am going to do the roof on my lil fella with foam board from foamex in bayswater [melb]. $70.00

Trouble with being out here is that almost everything costs double due to the freight involved. I'll try the local clark-rubber/foam stores (150km away) to see if they have any 30mm foam, you're right though, it does make a good insulator, I was additionally thinking of putting reflective/blue wrapping foil on one side just to stop it falling apart from random strikes as well.

Paul.

[old_picker]

Actually that should read polystyrene instaed of foam.
Doubt clarke rubber would have it.
Wherabouts are you??

[inflex]

Just phoned up a "local" supplier (I'd have to drive in to pick it up, 320km round trip), will cost me about $16/sheet for 3600 x 1200 x 30.

Trouble is that my shed roof panels are 3000 x 1500 :mad:

[Jedo_03]

Just phoned up a "local" supplier (I'd have to drive in to pick it up, 320km round trip), will cost me about $16/sheet for 3600 x 1200 x 30.

Trouble is that my shed roof panels are 3000 x 1500 :mad:

Gets slide rule out..
3600 - 3000 = 600
600/2 = 2 @300
1200 +300 = 1500
So 2 of 3600 x 1200 will give you 2 of 3000 x 1500 remainder 600
Looks right
Cheers
Jedo

[inflex]

Here's something else though that I worked out - I can do the whole 6m shed including the walls with 10 sheets, here's how...

Wall height = 1.8m
Ceiling = 1.5m
So I need 3.3m per shed "half". The shed is 6m wide, so that's 5 widths of 1.2m foam and I'll have an excess cutoff of 300mm x 1200mm (which I'll use collectively for the end walls).

The next trick is the lining, I'm thinking either of 3~4mm ply or random-groove ply (for a nice 1980's look ). Sheets that I obtain here are 2400x1200.