DIY Doctor UK DIY Forums

I'm thinking of adding a porch. It would be joining an existing rendered cavity wall and part is stone/slate cladding. Are cavity trays needed for rendered walls or are they just required were the extermal wall is face brick? There is also some foam insulation in the cavity.

you dont need cavity trays,the render is providing protection to the elements

thanks for reply, just curious, am I right in what I said previously, are cavity trays only needed for facebrick walls?

cavity trays are needed over lintols but not needed on a gable end

ah so i will need them as the porch would be in front of an existing doorway?

if the render is cementitious based it will still need cavity trays. we detail cavity trays over all openings

For readers looking for related advice please see our cavities DIY how to projects pages which covers stuff like damp issues and fixes, vertical Dpc, insulation of cavities, cavity trays and lintels and pumped cavity walls.