Gone West

We used timber studwork covered in 12mm Hardiebacker board in all our bathrooms.

That's interesting, our trims were steel and were screwed down and the membrane was welded to the trim.

The problem is, who does that? To ensure it is correct would mean educating the masses about WC, who don't want to be educated about 'boring stuff'. As has already been said, finding professionals who can do it is difficult enough.

I don't understand. The underlay used is a material that looks like a dark green nylon pot scourer and isn't visible in the last picture 😕.

IIRC the upstand is on top of the underlay.

These are the best I've got, sorry.

I'll have a look, probably not from close to.

We had a Sika single-ply membrane installed on a small extension a couple of months ago. The edge trim upstand is a steel profile covered with a membrane. The profiles were fitted first, then the underlay and then the roof membrane was welded to the profile. The edge of the roof was just a double layer of 18mm OSB.

We've got a couple of sun tubes in our kitchen, but they have frosted plastic at the bottom. It's probably so you can't see the reflective tube. Incidently we're going to replace them with boxed in skylights sometime.

Welcome to the forum. I hope you are able to achieve what you want with the Planners. Looks like a lovely site.

We had back to back bathroom and ensuite which both connected to a single stack with an AAV. It was a snug fit and the BCO was interested but happy it was all ok.

When we built our house I went to one of the two Jewsons in the city as they specialized in timber, and we were building a timber frame. We spoke to the manager, explained everything, set up an account, and he gave us a list of all the products Jewsons stocked with the full price and our discounted price listed for everything. Those prices applied to the other Jewsons as well. Their timber was sometimes complete crap, but they always replaced it and often we kept the old stuff. They can be ok, but you do have to ask. Free delivery is useful too.

@Pbuc Fill the gaps in the brickwork by packing in mortar, then a coat of bonding plaster out to 3mm below existing plaster and skim to finish with jointing tape around the edges.

You're getting on at a fair rate of knots there. Well done, it's looking good.

As @dpmiller says pushfit and solvent are different diameters. This table may help. Pipe sizes and dimensions chart.pdf