How to build non-load bearing stud wall?

[ChrisLW]

Hi,

I am looking to build a stud wall in my garage, non load bearing as it is just to divide the space for different purposes. The garage is free standing single brick with double brick pillars throughout, the roofing material and supports are all hardwood.

I have worked out what I need and a lot of material I have viewed shows the top plate getting nailed or screwed straight into the roof timbers directly which I assumed was ok until I came across standards that make it pretty clear to not affix it directly but use other methods to attach with a gap to allow the appropriate movement.

With this new information putting a question mark over what I previously thought was fine (the bunnings video literally does this by the way, straight into the roof timbers), I am looking for some advice as maybe I am misunderstanding this requirement affecting what I am trying to accomplish? (A dividing wall basically).

[JacobZ]

Hi @ChrisLW,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

It is always important to follow the National Construction Code, as well as the Australian and New Zealand Standards, so if they call for a certain method of construction, then they should be followed. These standards are also complex and written for a variety of different scenarios that may not apply in this situation.

Having said this, I can't see a reason why you couldn't attach your top plate directly to the underside of the roof timbers. The only reason I can see this being an issue is if the weight of the roof pushes down on the wall, causing the stud wall to break under load. This is extremely unlikely to happen because the roof is already being supported by load-bearing walls. 

Do these standards you've read give a reason why they advise against it? Is it possible they are advising this for earthquake or cyclonic regions?

I know in earthquake-prone regions, construction calls for measures to account for deflection, which is the bending or displacement of a structural element under load. If the roof structure is not able to flex or move sufficiently under load, then it may cause structural failure of the wall. 

Having worked for a commercial linings and partitions contractor, we built to these standards because we were in large commercial buildings with suspended slab floors and ceilings that in the event of an earthquake could "bounce". In a residential application with a timber roof structure, I can't see a reason why this would apply.

If you can point me towards the standards, you are looking at, I would be happy to read and interpret them for you.

Also, allow me to tag @Nailbag for his thoughts.

Jacob

[Nailbag]

Hi @ChrisLW 

Other than any building regulations due to your location, which is worth checking out as per @JacobZ recommendation. The main reason for that would be to cover yourself from an insurance standpoint in the unlikely event the new wall caused an issue. Insurance companies are always looking for an out.

Other than that, I would build the frame just nicely flush with the plasterboard or even a few mm shy, and then use packers at the point of fixing to make it easy on yourself and allow for an uneven floor. The side walls can then match the frame and use quad/trim to neatly cover the gap. Again to make it nice and easy on yourself.

Nailbag

[Noyade]

I followed the advice of the late Shirley Strachan from Skyhooks fame when he was a presenter on the TV series "Our House."

Glue battens to the ceiling and extend down.

In my case it was second grade MDF attached to a wood framework.

So, this corner is 'fake' so to speak - no load bearing.

[Nailbag]

Hi @Noyade 

I used to work on Shirl's Neighbourhood back in met early Ch7 days. and a good mate of mine was his technical advisor on "Our House" Basically anything Shirl would cover building wise came from Ed.

Nailbag