Soundman2020 - Studio Design Forum

The challenge is to affix the insulation to your inside out wall in such a way that it will not slip down over time - fishing line and some hooks or nails would do the job.

Right! There's also these impaling spikes or clips that you can use for that: And these things too: sort of like a nail with a huge plastic washer on it:
One thing to be aware of with the cavity insulation: if there's a chance your slab might get wet, then use mineral wool rather than fiberglass. Mineral wool holds up to water a lot better than fiberglass. Since part of Gareth's place will be below ground level, this might be worth considering.

- Stuart -

Thanks for the help! I will find mineral wool for this, as even though the below ground bit will be surrounded by a waterproof membrane with a french drain around that there could be condensation in this cavity.

Those spikes and I splint clips make sense although seem harder to come by in the UK. I’ll search some out!

Gareth

garethmetcalf wrote:Source of the post Those spikes and I splint clips make sense although seem harder to come by in the UK. I’ll search some out!

There's a simple, ugly, DIY hack for that: you can make your own by hammering a few nails through small pieces of thin plywood, then attaching those to the wall surface.

But, as with all pointy spiky things, do take care with those! They can hurt you pretty bad if you aren't careful...

- Stuart -