Looking to buy a cottage, but it will need a full length extension to the rear, housing a loo, utility area/ rear porch, and the remainder will be a shed/store.
Concrete block walls or timber frame? It will be single storey,with a lean to tiled roof, I’m good with wood, but not good with blocks, if it was to be timber, what would it be made up with? I’m thinking 6×2, clad on the outside with either shiplap,or rendered osb, some insulation of some description, breather paper,then maybe osb, then plasterboard and skimmed, any suggestions? Thanks

Personally, I’d go for block. More solid, better soundproofing. Never sure about the longevity of wooden buildings in the uk. Built my own extension in blocks. Not quick but easy enough. If you have the skills as a carpenter you’ll have the skills with blocks.
Rich.

You might struggle to comply with Building Regs Part L if you use blockwork alone.

Why would you struggle with part L?
Block work is a much better option if you’re gonna just render it anyway. Less work, quicker etc.
you would never need to go 6×2 if done out of wood. That’s way over engineered.

I am a bit crap with blocks so went with thermalite etc and thin joint system. Made putting up blocks very easy. Nice and light to work with, quick to put up.

the question you need to ask your self really is ….

do i want a house extension or a shed.

even if i was cladding in wood or doing a timber frame id still build a block structure.

Trying to sell a cottage with a wooden lean to shed with a toilet in it …. most folk will view it as a negative as oppose to the positive it is.