How to install battens in bathroom?

Hi @awl,

Welcome to the Bunnings Workshop community.

Have you got any photos of the area you are looking to batten out? I'm assuming that the need to batten out the wall means it is a masonry or concrete substrate? Also, can you advise the measurements of the plumbing that would need to be covered? This would help our members to give you some more specific advice.

James Hardie's Villaboard installation guide shows the minimum batten size to be 38mm wide but your choice for timber would all depend on what needs to be covered.

They also don't recommend a specific sized fastener for attaching to walls, stating only to "Use suitable masonry fasteners to securely fix timber/steel battens". Without specific advice, my approach is to always over engineer. Depending on the eventual width of the timber, and the thickness of the substrate, Ramset 10 x 120mm Zinc AnkaScrews at 300mm centres should do the trick.

If you let me know answers to the above questions, I'll happily investigate further and offer more tailored advice.

Jacob

awl

Thanks Jacob, I'll come back with the details.

Hi @awl,

The advice I've received from James Hardie is that a standard 70x35 stud on its flat should be an adequate timber for this application.

Let me know when you've got those details and I'll be more than happy to assist further.

Jacob

awl

Apologies Jacob, have been unwell but back in board now. The walls are brick and the plumbing I'm concerned about is the two hot and cold water lines that run the height of one wall but are installed in the corner and adjacent to a second wall.

Hi @awl,

I'm sorry to hear you've been unwell, but it's great to hear you're better and ready to crack on with this project.

Looking at the space, my advice would be to use 70 x 35mm MGP10 H2 Pine Framing attached to the brick with Ramset 8 x 75mm Galvanised AnkaScrew Masonry Anchors at 450mm spacing the full height of the timber. Make sure your AnkaScrews make solid contact with the brick as opposed to the grout lines.

You can then use Villaboard Lining to line your bathroom, noting that there are different methods of attaching the Villaboard based on whether it will be tiled over or not. For wet areas, you can use the Villaboard Lining Installation Guide in conjunction with the Wet Area Construction Application Guide to ensure you meet the required standards for wet areas. Page 6 of the Wet Area Construction Application Guide shows an example of how you would normally deal with corners in wet areas.

There is quite a bit to it and as waterproofing and plumbing are licenced industry, you're going to need some assistance from a waterproofer and a plumber. I'd suggest having them come in to quote early in the project so you can discuss the best method of handling that corner to ensure you meet the required standards.

Let me know what you think and if you have any further questions, please don't hesitate to ask.

Jacob

awl

Thanks Jacob.

Can you use the stud with either side to the wall?

I want to box out by 90mm, so can I use a 90x45 stud with the 45 side facing the wall?

I also intend on fixing a 900mm wall hung vanity to the wall, with these size studs be sufficient for that?

Hi @squeakysim,

Yes, you can use the 90x45 on either plane.

90x45 timber is more than adequate to support a wall hung vanity as long as you use quality screws in a suitable size and length.

Let me know if you have any further questions.

Jacob

Thanks @JacobZ

I intend to box out the wall by 90mm to allow space for plumbing and waste and electric. I'm fixing to a brick wall with plaster finish. The battens will be covered by 6mm villaboard ready for tiling.

What would be the recommended batten size and fixing type factoring in that a 900mm vanity will be attached to the battens aswell?

Would an 8mm coach screw be sufficient? The screw will be countersunk, but how deep should the screw go into the wall, is 50mm enough?

Thanks

Hi @squeakysim,

You'll find batten details for Villaboard in the installation guide. Their minimum thickness must be not less than 38mm. So, that would allow you to use either 70 x 45mm or 90 x 45mm.

Fixings for attaching the Villaboard to the battens would be 30mm x 2.8mm Galvanised FC Nails.

Please let me know if you have further questions.

Mitchell

Thanks @MitchellMc

My question about fixings was about fixing the batttens to a brick wall. Given the 90mm depth (minus 10mm countersink), I thought that maybe 130mm length would be sufficient, giving 50mm bite into the wall...?

Hi again @squeakysim,

You'll essentially be building a stud wall in front of the brick rather than attaching battens to the wall directly. So the bottom plate gets attached to the ground and the top plate to the timber structure above, the vertical studs are fixed between the two with timber screws.

Here's a helpful guide: How to build a stud wall.

Mitchell

Ah right! I hadn't thought of it that way! That would save the need for all the fixings to the wall wouldn't it?!

However, I currently have no floorboards down, as the plan is to bring the plumbing up through the floor and inside the new wall cavity into the vanity. So I can't fix a timber to the floor. So I think maybe I don't have a choice but to fix to the wall as if they are battens. What do you think?

EricL

Looking at the photo you posted earlier in the post, it appears that you have a concrete floor. Please let me know if I am looking at this incorrectly, the ceiling does not have a cover on it. Technically your wish to run the water pipes through the battens will still be possible and the timber base plate can be anchored to the concrete floor. As for the ceiling the top section of the stud wall will need to be anchored to the brick wall. This will still allow you to build the stud wall in the traditional manner.

However, if you are hanging a vanity onto the stud wall then it would be prudent to anchor those timber pieces to the brick wall where the vanity will be screwed into. Adding noggins is also a good idea as this will allow you to attach more traditional screw fixings to the wall.

If you need further assistance, please let us know.

Eric

Thanks. Sorry if i've confused things, but I'm not the OP! I've piggy backed on this thread as it was dealing with the same topic I was looking for help with.

Below is the space I'm working with! As mentioned before, the floorboards have now been taken up. The wall on the left is going to be built out 90mm and the vanity attached, the far wall is also going to be built out but only half height and the same 90mm depth. The question still remains for where I need to fix to the wall, what are the best fixings and how deep should they go into the brick work? Thanks

EricL

My apologies for the miscommunication. Early in the discussion Jacob suggested using Ramset masonry screws, I suggest looking at the Ramset 12 x 150mm Galvanised AnkaScrew Masonry Anchor - 20 Pack. I would not advise going lower than 130mm in length. When attaching 90x45mm timber on its tall edge (90mm vertical) to a 100mm thick masonry wall (for example), the general rule of thumb for masonry screws (like Dynabolts or concrete screws) is at least 40 to 50mm of embedment into solid masonry, but not so long that it risks blowing out the back of the wall or compromising its structural integrity.

My best advice is to drill pilot holes both in the timber and the masonry wall to avoid cracking or weakening the wall. I still suggest adding extra support screws to the area where the vanity will be hung and adding noggins to the studs you'll be installing.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

Nailbag

The most common way of fixing a parallel timber stud wall or any other internal wall for that matter, is through the top and bottom plates into joists with additional fixing points tied to the wall for additional strength depending on wall height and what additional loads may be fixed to the front of it once completed. Top and bottom plate fastening is usually done with a railgun. Otherwise 14ga 75mm or greater bugel/ batten screws can be used.

Both the left and rear walls would be fixed directly on top of the floorboards matching the spacings of the joists. You would drill pilot holes through the 45mm bottom plates and then drive 100mm batten screws to fasten. Basically the same again for the left hand wall top plate. The cornice needs to be removed, then the fastening points need to match the ceiling joists. If they are running the wrong way, then you will need to get into the ceiling space and install noggins to accomodate the fixing points. This video shows the process.

For added strength and stability you can fix right-angled brackets to the studs with screws and masonry screws back to the concrete wall. Or fix short off-cut timber blocks to the wall against studs to save the expense of the brackets. This is also how you would secure the top of the rear wall frame.

Some additional supporting photos below.

Regards Nailbag

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Thanks @Nailbag and @EricL

I fear I have confused things a bit by not providing all relevant information in the first place!

I want to build the wall before I lay the floorboards, to make the plumbers life easier, and ultimately save me money! The ceiling is concrete (I'm in a groundfloor unit) so I'll need to use revelant fixings to attach the top plate on the left. But, the wall at the rear is not going to be full height as that is where the walk in shower will be, and I want to create a ledge. So the top plate will probably need to be fixed to the wall instead.

The more I think about this, I wonder if I can get the plumber to do their work first and I build the wall in post rough in... It would certainly make the construction more straightforward by the sounds of it!

Side question - the flooring is going to be Hardie Secura board, can you nail into that in the way that you describe when fixing the floor plate?

You'd likely need to pre-drill and screw through it @squeakysim.

It's always difficult working around trades. It might be worth asking the plumber whether constructing the frame will cause them any issues and what they'd prefer you to do.

Mitchell

Dave-1

Good Morning @squeakysim

Mmm A lot of the wall questions I would say I am learning as much as you as you travel along. If you have the stud wall offset from the brick wall even by 30mm then you could run services behind it? (Not sure of the ruling for that) That way things could be roughed in and then you can construct the wall.

Having the wall directly on the beams instead of the floor sheeting, Most times Ive seen it the floor sheeting goes down first. But that is only observational data. The load of the wall needs to be transfered down to the floor joists then beams would be my main thought. So the flooring would be down before the wall?

And sorry I have not used the Hardie Secura board, will leave that to @EricL or @MitchellMc

Dave

Yeah, I guess I could build the wall directly on to the joists, and then butt the floor up to the wall. But that would only work where the joists run perpendicular to the wall I'm building. Along the left wall the joists run parallel, so I'd probably need to add another joist to ensure there is enough of a platform for both the floor to attach to as well as the wall.

Does anyone see any issues with fixing the wall directly to the joists and then butting the floorboards up to it?

Physically, I don't see an issue @squeakysim. It's important to consider how this joint will be waterproofed, so it might be worth consulting whoever is doing your waterproofing to see if they have any issues.

As far as I'm aware, there should be no issue sealing that joint with polyurethane and then waterproofing over it.

Mitchell

Nailbag

@MitchellMc makes an excellent point in speaking with your plumber first. It's always a good idea in having all your trades people in early so they are across the project build and can advise on what they need from you and vice-versa. When it comes to plumbing rough-ins, it's also a good idea to have already purchased your fixtures like shower rose, wall mounted spouts and taps and mixers. These will all have their own internal wall fittings the plumber will need in planning and roughing in. And if you're considering under tile floor heating, which is getting very popular these days as new affordable models hit the market to get your sparky across its requirements.

Regarding the Hardie Secura Board, my understanding it would sit within the walls, not the walls fixed on top of it. @MitchellMc maybe able to confirm this or contact the suppliers advice line.

Nailbag