I have a new 20'x7' shed which my wife will use as an artist's studio.
The shed is heavy duty T+G. I want to insulate the walls and roof.

My local Sheffield Insulation Trade Counter recommends new-fangled
stuff called "Frame Foil" stapled onto the uprights of the shed walls,
with "moisture board" directly on top of that. But it will be pricy -
I reckon about £600 for the Frame Foil alone.

1. How good is "Frame Foil"?

2. What alternatives are there? Preferably cheaper...

3. Could I use T+G pine cladding?

3. What gaps do I need between "moisture board", insulation and
outside walls?

4. There will be a 5-socket ring in the shed. What is the best way to
get the connections to the electricity sockets through any wall
covering/plastic membrane/insulation?

Many thanks to all