Kingspan K118 or Woodfibre IWI

[wokingham74]

I am in the process of renovating an 1879 mid-terrace. The property has a cavity wall (early type where external stone is turned "sidewards" and ties into brick inner leaf.

I am looking to insulate the inside of the house and am torn between insulated plasterboard such as Kingspan K118 or Limegreen IWI with woodfibre boards. I know they are both totally different systems but would like to know if people have used either on Victorian terrace properties and what you'd recommend.

 

[jeds]

K118 is about four or five times better insulation value than wood fibre board, and also provides you with a vapour control layer. Personally I would go for standard PIR board fixed in place with battens + VCL and plasterboard over.

 

[George_engineer]

If you've a ventilated cavity then the kingspan shouldn't cause adverse effects on the wall.

Wood fiber has other benefits that can help offset it's higer thermal conductivity - a higher density (leading to a good thermal decrement delay), no potential issues with degassing and behaves hydroscopically to help control humidity/control interstitial condensation. However unless you are going for a more sustainable option then wood fiber generally only gets used if the wall is solid and built from lime mortar.