How to insulate and plasterboard Colorbond shed?

Question

Hi, I’m starting the reno of my shed. I’ve just got the floor epoxy’d, now I’m looking at insulating and cladding the walls.

This is my first time doing this, so I’d like to check whether my plan will be OK.

Fill all gaps with expanding foam.

Insulate using 25mm foil boards. I’ll glue spacers to the metal walls then glue the foilboard to the spacers to create an air gap.

I don’t want to build out a whole wooden frame, so I’ll attach plasterboard directly to the metal frame, which will also leave an air gap between the foilboard and plasterboard. I’m not sure whether plasterboard is best here, or whether I should use 9mm plywood instead?

my reason for plasterboard is that it seems cheaper, provides a smoother finish and I’m not intending to hang much on the walls, maybe just a TV.

does this approach sound OK? Thanks

MitchellMc · Answer

Top hats would be suitable if you can find them in the correct depth @ben1984.

Foilboard is a solid choice. You could use Earth Wool, and a vapour barrier would be relatively easy to install if needed.

Mitchell

A note to our New Zealand members: The use of foil-based insulation products is prohibited.

ben1984 · Answer

Thanks Mitchel. Can I use top hats to create vertical studs and mount the plasterboard to that?

Also do you think Foilboard is the best choice? I was thinking earth wool, but I don’t know how to create a Vapor barrier.

thanks

MitchellMc · Answer

Hi @ben1984,

Your approach sounds great right up until the plasterboard is attached. With the current metal frame, you will not be able to install the plasterboard as per guidelines; you'd need far more vertical fixing points. Here's the installation guide.

I see your posts are proud of the horizontal metal frame pieces. Are you planning on fixing the boards onto the posts? If so, I'd run a series of vertical timber studs at the correct increments of 600mm centres to adhere to specifications. That should be fairly simple, just use Zenith 10G x 65mm Galvanised Countersunk Head Metal Screws to attach the verticle studs.

Your stud selection will be based on the height difference between the horizontal metal frame and the vertical post. Say it's around 35mm, you'd use 75 x 35mm H2 Pine.

If you plant to leave the vertical studs exposed and place the plasterboard between them, then you'd need to install studs between the horizontal metal frames and flush with them.

Obviously, if you have a TV or such to mount, just stick a bunch of extra studs in that area to accommodate the mounting points.

Please let me know if you have any questions.

Mitchell