I have a single skin porch which was originally built as a porch but previous owner has knocked through to hall to enlarge. Don't want to put another door in to original house or add an interior block wall as will make space unuseable, but keep getting really bad condensation on exterior porch walls. What can I do to make the exterior "porch" walls less susceptible to condensation - line them?
You could try a dry lining with battens, insulation, vapour barrier, plasterboard and finish. But then you will need new skirts, and possibly little window cills on top of lining. It is also no guarantee, depending on your exposure and temps etc.
You might consider a little wall mounted heater or better still can you get a rad out there?
Sorry, not to be a ray of sunshine but it is always going to be tricky to cure this kind of problem on a single skin!
Also, be careful as it may contravene building regs/planning if you need to sell it now that it has been opened up.