How to add bracing for external wall?

[Sopwith]

The Bunnings workshop is so helpful. I hope you might be able to help solve a puzzle I have.

Two of my friends are each building a timber-framed shed, 3mx6m. In each case, the plan is taken from instructions online by (I can't recall the exact name) but think it is a Timber Industry association. The plans claim that they are suitable for the type of location my friends have.

One friend is using a technique I've seen many times - bracing the wall frame with galvanized straps, diagonally arranged, in a cross, with a butterfly tensioner.

The other - who has spent time in north America - is using structural ply. This is being nailed, as per manufacturer's instructions, which cite the NCC. I'd seen ply bracing near corners or door ways, but not an entire build, but gather that is usual in North America.

In both cases a vapour wrap will be fitted and then timber cladding, over battens. The timber frames will be stuffed with insulation, prior to the lining being fitted. One shed is to be a darkroom; the other, a writing space / hobby room.

The location of both sheds is southern Tasmania.

My questions are:

1. Is there any difference between the two bracing techniques - or is preference down to cost?

2. If bracing is via structural ply, is the vapour wrap still necessary?

The two approaches have provoked quite a bit of friendly discussion.

Thanks for reading.

[MitchellMc · Accepted solution]

Hi @Sopwith,

Both metal strap bracing and structural ply bracing are effective, with the choice depending on cost, material availability, and structural needs. Metal straps provide tension resistance, are lightweight, and allow for larger openings, while structural ply offers superior shear strength and can be easier to install. Ply bracing is more common in North America but is gaining popularity in Australia, especially in high-wind zones.

A vapour wrap is still necessary with ply bracing as it alone does not provide a weather barrier. Vapour wraps protect against moisture while allowing vapour to escape. This helps prevent condensation and improves the durability and thermal efficiency of the shed.

Please let me know if you have further questions.

Mitchell

[Sopwith]

Hello Mitchell

Thank you for a prompt reply and very informative too.

The area where the sheds are being built is N3, and both sheds have one end face into the prevailing winds. I recall the discussion did include a too and fro about shear forces.

Thanks again. I'll be interested in seeing how my friends' sheds turn out.

S.