What is the thinest wall that meets regs?

[wadge]

I'm building a single storey extension (WC/shower and utility room). However, width is at a premium, only about 2.1m external measurments, therefore every inch counts.

What is the thinest wall I can build (block as it will be rendered) that still meets regs? The building officer said look on the net and didn't give me much info at all, other than saying using a good block, I could possibly get away with a 50mm or 70mm cavity (depending on insulation type).

I was thinking single skin and studded on the inside, but what is a good block to use and good insulation?

 

[Fluffster]

You are going to have to go for a thermal block such as celcon, thermalite etc.
Insulated with rigid foam such as kingspan or xtratherm.
The thickeness of both depend on your loading and the u value that has to be achieved. I believe 100mm is as thin a block around, I maybe mistaken.
Have a look on ech manufactures web sites for detailed info.
Pete

 

[memor maplin]

Solid walls (no cavity)
In blockwork minimum is 250mm block.
Brickwork is one and a half bricks thick 327.5

The internal wall can be battened using continuous timbers along the top and bottom of the wall ,vertical timbers and noggings Insulation can be inserted in the squares, covered by a vapour control layer (polythene sheeting) then plasterboarded.

Memor

 

[NS215]

sounds like a timber frame construction to me is the way ahead

 

[freddiemercurystwin]

SIPs panels are about the thinnest, they're the next big thing imo eg http://www.sipbuildingsystems.co.uk/Technical-Papers.aspx

 

[wadge]

Thanks for the advice. Will look into the panels.

BC want a U value of 0.35 so will read up to ewhat can be achieved with these panels.

 

[freddiemercurystwin]

SIP's fart in the face of U values! eghttp://www.siphome.co.uk/structural_insulated_panels.htm
http://www.siphome.co.uk/Standard_Details.pdf page 15

Quote The total wall thickness of the Kingspan TEK Haus Building System, including the external weather protection, can be as little as 194 mm.