Pre 1900 built Solid brick wall - Insulation Advice Needed

Hi,

I'm currently renovation my building that was built in 1896. A solid wall construction 3 brick thick.

Building Regs want me to achieve a U-value on my external wall of 0.35

I can't seem to find what my current U-value is on the net.

Can some help me, and advice solutions to achieve my target please

Thanks

Kalp

 

Thank D.A. Was a good read

I read up on some PIR brochures and worked out that I need 50mm

Problem I now have is that without thinking I pre bought a shed load of 12.5mm PB and various sizes of timber, so I have to make good use of those.

I have spoke to a couple of people about the best way to to do the timber frame:

1. To use my 2x2 battens at every 400 mm,50mm insulation, the cross batten with 2x1, then board after services installed

2. To use my 4x2 timber to build a frame at every 400mm, 50mm insulation, leaving a 25mm "breather" then board after services installed.

Option 2 makes more sense to me as less labour required compared to option 1.

Would option 2 comply with building regulations???

I've been warned to make sure BR signed off before plaster boarding which makes sense too.