Insulation?

[Qbgrey 4,259]

What size timbers are the shed walls??? What cladding you having externally and what you putting on walls internally??

[Francie, 2,751]

24 minutes ago, Qbgrey said:

What size timbers are the shed walls??? What cladding you having externally and what you putting on walls internally??

Tongue an groove cladding,thick stuff,then the timber are two by 3s,an iv got 12mm 8by4 plastic sheets to cover up qbrey

[Francie, 2,751]

Just now, Francie, said:

Tongue an groove cladding,thick stuff,then the timber are two by 3s,an iv got 12mm 8by4 plastic sheets to cover up qbrey

The plastic 8by4 sheets are the same as the stuff they use in election boards I think

[dogmandont 10,060]

51 minutes ago, Francie, said:

The plastic 8by4 sheets are the same as the stuff they use in election boards I think

Have you building paper between the stud and the outside cladding Francie. 

[Lenmcharristar 10,247]

8 hours ago, Qbgrey said:

Having celotex with air gap on roof side is good but you need vented soffit/ badge/ fascia or you won’t get air flow. Same with a floor it needs venting

And the winner is this post

[Francie, 2,751]

1 hour ago, dogmandont said:

Have you building paper between the stud and the outside cladding Francie. 

Yes lad,there's good breathable membrane in between stud an cladding

[Francie, 2,751]

1 hour ago, Lenmcharristar said:

And the winner is this post

Have you used this stuff len?

[dogmandont 10,060]

Just now, Francie, said:

Yes lad,there's good breathable membrane in between stud an cladding

Polystyrene between the studs and sheet over the top Francie, you can buy the polystyrene in 8 x 4 sheets of varying thicknesses, far cheaper than kingspan and plenty good enough for a shed. 

[Francie, 2,751]

1 hour ago, dogmandont said:

Polystyrene between the studs and sheet over the top Francie, you can buy the polystyrene in 8 x 4 sheets of varying thicknesses, far cheaper than kingspan and plenty good enough for a shed. 

Thank you lad

[fireman 11,354]

9 hours ago, Goly said:

Yeah, that would be disastrous for the wood, no way to breath and full of moisture, it would rot something rotten.

It does and i don't think you can get mortage with foam over the roof timbers any more...

Edited January 30 by fireman

[dogmandont 10,060]

32 minutes ago, fireman said:

It does and i don't think you can get mortage with foam over the roof timbers any more...

They put card over the timbers now, as well as leaving a cavity between the felt and foam for airflow. Still wouldn't use it in my house. 

[Qbgrey 4,259]

Sounds good I’d go 3x2 studs as you said with tyvek over external timbers with your t@g boards this will let in air in as tyveks very breathable and let’s wind in then 50 mm celotex on the inside flush that will give you a 25 mm air/ breathable gap, then some osb or similar on inside . Forget polystyrene it’s u value is shit. 

[mC HULL 15,546]

10 hours ago, Francie, said:

Thank you lad

if you have vapour barried it which you have then any insulation is ok mate even rockwool which is what i’d use have used mate you don’t need an air gap on walls and the plastic cladding is great but the thin stuff is hard to put up flat if there isn’t board behind 

i

[mC HULL 15,546]

9 hours ago, Qbgrey said:

Sounds good I’d go 3x2 studs as you said with tyvek over external timbers with your t@g boards this will let in air in as tyveks very breathable and let’s wind in then 50 mm celotex on the inside flush that will give you a 25 mm air/ breathable gap, then some osb or similar on inside . Forget polystyrene it’s u value is shit. 

i can remember tyvek first coming out lol 

i was working at burtons before it was all black tar felt 

[dogmandont 10,060]

1 hour ago, mC HULL said:

if you have vapour barried it which you have then any insulation is ok mate even rockwool which is what i’d use have used mate you don’t need an air gap on walls and the plastic cladding is great but the thin stuff is hard to put up flat if there isn’t board behind 

i

We've used fibreglass, kingspan, rockwool and polystyrene in wall construction, it all comes down to budget.