How to line and insulate my lean to after rebuilding? Information, help and advice on many architecture, self build and design problems and issues

[CaptainSillyboxes]

Hi all

I've rebuilding a lean-to on the side of my house. It measures 2500mm x 900mm. It has concrete base, 3x2 walls,15mm external cladding, osb roof with rubber covering. Here are photos so far

We are going to put the washing machine and tumble drier in it and I would like to insulate it. I have some 8mm timber t&g to cover the insulation.

It won't have direct heating but will receive heat (and humidity) from the tumble drier and some heat will enter from the kitchen through the cat flap.

Do I need a breathable membrane behind the insulation?
Do I need a vapour barrier in front of the insulation?

Any other considerations I should be thinking about?

thanks!

[stoneyboy]

Hi captainsillyboxes
Yes to breathable membrane, yes to vapour barrier and don't forget ceiling.
Regards S

[B4Less]

Vapour control layers are recommended for use to the warm side of the insulation, it combats the passage of vapour through the wall. Breather membranes are used externally behind the cladding, these protect from wind driven rain while allowing air to pass through. Make sure to use associated tapes to tape and seal both correctly. (Double & single sided tapes)