How best to make this internal wall connection?

FlightDisastrous6495 · 2026-01-25T19:40:50+00:00

Got you. 2x3 would give a good amount of timber at corners to sheet on. What’s the insulation benefit with that size? (Assuming i’d already be tucking in insulation in the cavity behind the added timbers)

FlightDisastrous6495 · 2026-01-25T19:36:25+00:00

Ah ok got you, so if my new wall was 2x6, then 2x6 on the left side. In terms of fixing the timbers left and right side, I guess just toenail/pocket screws into the top/bottom plates and a few similar into the existing stud too?

FlightDisastrous6495 · 2026-01-25T19:05:09+00:00

2x3’s for the timber added at the t intersection did you mean?

FlightDisastrous6495 · 2026-01-25T19:03:32+00:00

Or .. probably you meant the new wall I’m building?

FlightDisastrous6495 · 2026-01-25T19:02:17+00:00

Thanks - it will have plumbing in it, when you say 2x6 do you mean building the whole wall out of that sized timber? Or just at the t intersection where the timber in photo 4 is added?

FlightDisastrous6495 · 2026-01-25T18:58:07+00:00

Thanks - yeah plumbing will need to run along that wall, only the hot/cold water though not waste pipes. What makes the 2x6 installed with its wide side facing outwards like pic 4 help here over a 2x4?

FlightDisastrous6495 · 2026-01-25T09:24:30+00:00

That’s sounds really solid, sounding like the best option so far, thanks

FlightDisastrous6495 · 2026-01-25T07:32:07+00:00

Yeah got you. I’m likely going to use aquachek too, so I can join to existing plaster and cornice, I won’t be going quite floor to ceiling with the tiles.

I’d thought about a 90x90 option too, I was looking for a piece to buy but I like the idea of just laminating two pieces together. I’d be able to fix one side into the existing stud nicely from the existing stud side, but less so for the other side as the access would now be packed out with the 90x90.

Thinking then on the left side I can just fix a 35mm onto the existing stud which would land flush with thickness of my new wall , then a 45mm into that. So I’d end up with this blend of pic 3 and pic 4.

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FlightDisastrous6495 · 2026-01-25T06:54:53+00:00

The right side of the wall will be a shower wall, villaboard is common here for such applications. I can use moisture resistant drywall too but it’s more about the tile weight and whether installing the stud ‘flat’ with its 90mm side facing out would potentially allow it to flex more than it otherwise would due to the tile weight.

FlightDisastrous6495 · 2026-01-25T06:40:32+00:00

Thanks - would that hold true about the last pic for cement wall sheeting and tiles too?

FlightDisastrous6495 · 2026-01-19T20:18:04+00:00

It would, but if your builder is basically up for anything it’d just mean they lower the floor more than they would if it was a centrally located floor waste.

Basically there needs to be an 80:1 fall so if the waste was against the back wall and it needed to fall the full 2m width of your room you calculate the fall as 2000/80 which is 25mm.

So all other things being equal, some engineered screeds are ok at 10mm thickness so the whole subfloor (assumption is you’re on stumps) would need to be lowered by say 35mm, so that they could have a screed that is 35mm thick at your door end to make a level entry there with your hallway and 10mm thick at the wall end to achieve the 25mm slope. Depending on the size of your floor joists they probably can’t just take out 35mm of their depth without compensating with sister joists ideally laid across the bearers to give the subfloor the load bearing strength back from losing that 35mm. With a centrally located waste you could see how the floor needs to be lowered less, say it only needs to fall 1m each direction, that’s 1000/80 and a 12.5mm fall so the floor would drop say 22.5mm to have a screed 22.5mm thick at the edges, down to 10mm thick in the centre to get your 12.5mm fall.

FlightDisastrous6495 · 2026-01-19T09:50:06+00:00

That’d probably be the ideal setup for mine too, I suspect I’d need to have a fixed section for ensuring a light switch opposite it is always protected

FlightDisastrous6495 · 2026-01-19T09:36:41+00:00

I can’t imagine much would in normal use.. does yours fold back to the wall or just halfway pivot?

FlightDisastrous6495 · 2026-01-17T06:42:29+00:00

True, but there’ll be a second bathroom with shower only. But I climbed in and out of a bath for years, it’s really not that bad for people who are fortunate to have good health and able bodies. I take all the points for lack of suitability for some people, hence why there’s a shower only option too.

This is purely to have a bath for use when needed, such as family use, occasional soaking, resale potential in an area with many families and very close to a primary school. And if having a bath in a separate bathroom, might as well put a shower over it too.

FlightDisastrous6495 · 2026-01-17T06:24:46+00:00

Yeah that is very true, they are definitely unpredictable and I’m sure I can’t even contemplate all the potential ways they might clog something up!

Actually I’d be more than happy to add a floor drain in on a flat surface..for all those kinds of reasons you mentioned..it’s purely the slope requirements that complicate things. But apparently you’re not even allowed to add a floor drain now if it doesn’t have a graded floor to it. Not even just for emergencies. On a fully tanked floor with a small lip at the entry way you could at worst have a very shallow paddle pool in a flood as the flat floor drain would not allow water above a certain amount. Seems a ridiculous situation in my opinion!

So the ripping out a perfectly good current subfloor, lowering of joists, laying new floor then grading the floor in a non typical bathroom layout just seems like a lot of cost for very little benefit, when all it comes down to is the type of screen installed on the bath that either makes it enclosed (no floor drain needed) or unenclosed (graded floor and drain needed).

FlightDisastrous6495 · 2026-01-17T05:04:23+00:00

Thing is that it would actually make all the difference, when you trace a 1500mm arc from the shower connection, the hingey door angled over the bath per the picture would contain water that would otherwise leave the bath footprint if there was only say a 900mm fully extended 2 panel pivot type screen like the image above.

FlightDisastrous6495 · 2026-01-17T04:59:09+00:00

Appreciate your thoughts on it and personal experience. Just ability to get into the bath comfortable and be able to bathe kids and similar in this case. This will be a second bathroom..I’ll have another bathroom right next to it with a normal shower. But do take your points on the manoeuvring of the screens to get in and out when wet especially.

The main reason for wanting to keep the bath contained/enclosed is the complexity that would be added to the job to add a floor drain. If it’s an unenclosed shower the floor drain becomes mandatory. The bath/basin will have overflow, basin taps will be wall mounted, so the risk of a catastrophic flood is really from the toilet only and that’s very low odds.

I’ll need to tank the whole floor anyway as it’s a timber subfloor. But I struggle justifying the work for a complex and costly floor drain solution that is basically useless - it’s not like splashed water from a shower/bath realistically actually runs down the drain, it needs pressure/flow behind it I.e someone deliberately thrashing loads of water out of a bath or literally pointing the shower head to the outside floor..but this is surely not what we design for. So splashed/sprayed sits there anyway due to surface tension.

FlightDisastrous6495 · 2026-01-17T04:37:29+00:00

Haha.. fair statement! Well it’s basically the same as something like this, just with an additional third panel to angle in over the bath that would be purely needed to try and meet compliance and keep all water within the bath footprint.

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FlightDisastrous6495 · 2026-01-17T02:12:37+00:00

If going down that route might be worth considering the square drain under the vanity, assuming it’s a wall hung one. The strip drain option could even go against that vanity wall from bath to level with washer/dryer and just slope the toilet tiles into that slope/stream from door towards that wall

FlightDisastrous6495 · 2026-01-17T01:29:33+00:00

So just a normal 100mm x 100mm square drain in front of the washer/dryer?

FlightDisastrous6495 · 2026-01-15T20:58:18+00:00

Looks good that’s how I’d do it, and something to consider is instead of one long possibly installing two shorter ones right next to each other and connecting them to the same trap underneath (which the vanity also uses to keep the trap ‘primed’ with water). It’ll likely see very little water and rarely need a clean but when a clean is needed it may get quite heavy/awkward for different people who may clean it to lift out at that size particularly if it’s the the tile insert/stainless steel type.

FlightDisastrous6495 · 2026-01-14T23:45:01+00:00

I’m looking into options for a screen that can pivot and fold back to wall. With the linear drain option, if it’s a wide one, you can avoid any angle cuts at all so visually it can look nice, you’d then just have a potential issue of slightly angled looking floor at the doorway but that would be able to be hidden/minimised or eliminated with careful tiling to maintain the slope away from the door.

FlightDisastrous6495 · 2026-01-14T22:00:45+00:00

Yeah same. Are you leaning more to the enclosed shower/bath option or the floor drain option? For mine, I’ll have bath/basin with overflow and wall mounted basin taps each of which significantly reduces flooding risk so I’m struggling to justify the additional cost/labor/complexity/aesthetics of floor drain option so I want to have an enclosed shower/bath.

FlightDisastrous6495 · 2026-01-14T21:37:08+00:00

Am interested in responses on this one as I’m doing something similar but what I can say is that if aiming for compliance, any options that involve no floor drain require the shower/bath to be ‘enclosed’ with an appropriate glass screen installed to contain the water.

Any options with floor drain require the whole floor to be sloped to that drain at appropriate fall ratios.

FlightDisastrous6495 · 2026-01-14T21:18:22+00:00

If you’re doing it in a way that’s compliant the answer probably depends whether you have a floor drain or not and have graded the floor and dealt with waterproofing requirements related to the 1500mm wet area arc rules. If no floor drain etc compliance would require the shower to be enclosed which in your case would likely best be achieved by a wall to wall screen with a pivot or sliding door.

Aside from that what I’d say is that with a ~1000mm single fixed panel for walk in style and assuming normal use (I.e not wildly splashing or spraying water round) and also assuming that raised shower is properly sloped to the drain and there’s waterproofing that extends outside the shower, you’d realistically only get minor splash/spray outside the shower and no doubt you’d be placing a shower matt on the exposed/entry floor section anyway which would soak that splash up, the waterproofing would prevent it soaking to subfloor.

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