existing extension on back of house made of 2 x 4 wood and?

Question

plaster board on the inside and wooden slats on the outside, not strong enough for double glazing, apart from knocking down existing walls to rebuild (leaving roof in situ), is their a way to strenthen what I have ?

Answer 1

take off plasterboard ,cover with building polythene over studs,erect new stud work around all exterior walls 2inches away, insulate between stud work with 4inches of fibre glass then plasterboard.

hope you got room to erect the new walls (good luck)