Cavity wall, insulations

[khan71]

Hi there I hope some expert can help me as I planning to built a externaland cavity wall and I will use 50mm insulation can somebody tell me actual gap in between two leafs. should it be 50mm or more then 50mm if more then 50m how much gap should be in between to leafs.thanks and regards

[stoneyboy]

khan71,
Direct reply to your question - you need a 75mm cavity and to fit clips on wall ties to hold the insulation against the inner cavity.
Depends what you are doing but if it is a house extension you need to meet regulations so thickneess of insulation will depend on construction esp inner leaf.
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