Site shed conversion

[musorob]

Hi there
I'm in Louth Park NSW Australia. I'm converting a building site shed on my farm. It's 7.2m x 3m x 2.4m(h), 75mm steel frame construction. Currently it has a thin gal steel sheeting on the outside and I plan to clad it with 25mm cypress pine weather boards. 1st question is can I leave the gal steel sheeting there and clad over it(easiest solution) or should I remove it and screw the cladding straight onto the steel frame? I'll be using insulation batts in the wall and lining inside with gyprock. Isolation is a moderate concern, with Nanna living in a granny flat nearby and occasional tractor noise from next door's farm.
There will no doubt be more questions for you but for now I'll just start with that one
Cheers
Rob

[Soundman2020]

Hi Rob. Please read the forum rules for posting (click here). You seem to be missing a couple of things!

- Stuart -

[musorob]

Hopefully all fixed :/

[Soundman2020]

Hopefully all fixed

Yup!

1st question is can I leave the gal steel sheeting there and clad over it(easiest solution) or should I remove it and screw the cladding straight onto the steel frame?

Good question! Acoustically there's not much in it (as long as there is no rattling between the metal and wood!), but from a practical construction point of view there might be issues, such as moisture condensing on the metal and causing rust or rot over time... You should probably check with building contractors in your area, to see what they do in this type of situation.

I'll be using insulation batts in the wall and lining inside with gyprock.

That's fine for the inside, but don't forget that you will also need a vapor barrier in there someplace: probably up against the drywall, but once again check with local contractors and check your building code, to find out what the legal requirements are.


- Stuart -

[xSpace]

A vapor barrier proper is required in cold climates. It was a development that allowed people to not have the house rot due to migration of condensation from warm side to the cold side. In a warm climate...IF it is required at all it would go on the exterior of the building.

What dictates does your assembly need a VB or not is that climate and the ability of the wall to dry out from the exterior to the interior or the interior to the exterior be part of the construction. This is dictated by the perm rating of the materials used to build with from exterior to interior exclusively.