Hovis builds a garden office*

mostly buried my head in the sand.

I found a few areas where the ants were actually coming in and out (rather than just pushing insulation through gaps. So i put poison down around those areas and sealed up everywhere else. It seams to have worked - but could just be they died out over winter, and are planning a come back?

The alternative of taking all the internal walls off, and redoing everything is not something i fancy…

My walls are plywood and simply held on with screws so I do have a relatively simple access route. Much machines and lots of wood racks all over the place so a total pita. I could also start remove cladding from the outside to have a look. There's also foam under the floor on the slab. Fml

Why not OSB for the walls? I’m just about to finish the frame for mine, so buying walls and vapour membrane is next for me

Aesthetics, I'm sure it's functionally fine.

This. At the time, birch plywood wasn't the price of gold, and looks much nicer to my eye.

Thanks. Did see your reply a page later. Yeah it’s not the prettiest stuff. Only for non visible areas only.