Bathroom drainage, number of downpipes, pre-walls, etc....

Good morning,

Stub gap = only a maybe 60 cm high gap, not room-high or floor-spanning.

Real stone was jokingly meant to be the [Kalksandstein] - from a structural point of view, it causes the least problems. We had it installed everywhere - even on the upper floor.

Hello Sebastian,

What is supposed to be wrong with downpipes in the exterior wall? Especially statically? That is a gap of 15 (?) cm – which of course must be taken into account in the structural analysis.

The greatest stress on an exterior wall is load transfer. Exterior walls also mark the protection between outside and inside, regarding temperature differences. So if you interrupt the wall – in your case a relatively thin aerated concrete wall – the shell builder usually has to reinforce this interruption with a reinforced concrete core. This also changes the calculation for the thermal insulation verification. You are building a two-layer wall; I personally would not want the drainage installed within the insulation either.

What I also consider essential is what happens if you have to access the “hidden” pipe? Right, you tear everything open again.

You can’t always drain/vent everything to the inside...

Every clever architect will recommend this option to you; box constructions are not so bad that they can’t be incorporated aesthetically.

Best regards from the Rhineland

The greatest stress on an exterior wall is load-bearing. Exterior walls also mark the protection between outside and inside, the topic of temperature differences. So, if you interrupt the wall—in your case a relatively thin sand-lime brick wall—the shell builder usually has to tackle this interruption with a reinforced concrete core.

What do you mean by reinforced concrete core? I really can’t imagine where you see something like that? A sand-lime brick wall is already load-bearing from 11.5 cm thickness and I can’t follow your argument—a window is also a weakening of a wall, as is a door. Here we’re talking about a 15 cm gap (not a chiseled wall)—the load does not have to be carried with great effort.

Also regarding temperature differences—you insulate the pipe and the intermediate space again. Don’t forget that sand-lime brick is not an insulating brick. It might be different with aerated concrete…

I happened to raise this topic at the time with the structural engineer and architect.

This also changes the calculation for the thermal protection verification.

No, because the thermal protection verification was ultimately calculated for this—normally no one makes such slots in the middle of the construction phase.

You are building double-shell; in the insulation, I personally would not like the drainage to be installed.

It’s not in the insulation, but in front of the insulation. I personally see no problem with that…

What I additionally consider essential is what happens if you have to get to such a “hidden” pipe? Right, you tear everything open again.

What do you mean by “everything”? I would then chisel open the slot covered by expanded metal, insulation & plaster and get there. The casing must also be torn open. There is a bit more mess with my option, but the effort is not significantly different…

Every clever architect will recommend this option to you; casings aren’t that bad that they cannot be incorporated aesthetically.

I consider my architect and also the shell builder quite clever and experienced (so you don’t need to disparage them) — a casing or routing outside the exterior walls would not have been possible—or should the things come down/up in the middle of the room?

Some might not care, but we do.

It just isn’t your taste, but technically I really can’t read anything against it from you…

What do you mean by reinforced concrete core?

I assume that - if the wall is interrupted - this weakening of the exterior wall must be compensated.

- a window is also a weakening of a wall, as is a door.

So you have no lintels in the house?

No, because the thermal insulation verification was ultimately calculated with it - normally no one makes such slots in the middle of the construction phase.

Of course this was calculated and "taken into account" before construction began.

I consider my architect and also the shell builder quite smart and experienced (you therefore don’t need to disparage them) - a boxing or routing outside the exterior walls would not have been possible - or are the things supposed to come down/up in the middle of the room?

It is interesting - you are rarely delicate in expressing your opinion, but if it goes the other way, you accuse “disparagement”? For your information: there are also people among architects who always take the path of least resistance. Whether this is sensible for their clients is for someone else to decide.

It’s just not your taste, but technically I really can’t read anything against it from you...

It has little to nothing to do with “taste,” I primarily consider the accompanying circumstances. Our architects would only agree to drainage in the exterior wall if there is no other way to divert the water elsewhere. It is also not about spoiling your execution, but merely about mentioning the circumstances. Rhineland regards

You assume, but there is no compensation...

I already understood what you meant – and that's how I responded. And you keep assuming... for your information: It was not part of our contract that we wanted no encasements. But we just like it the way he executed it.

I wouldn't care if you disparage it or not – you are not a professional in statics & thermal protection, but of course you have an opinion, as do I. And when two "experts" explain it to me, just as I had already thought, I first think that they are not entirely wrong.

It was only about how it is usually done – and I didn't describe more than that.

So with us there were neither problems with the statics nor problems with the heat loss Beton wurde in unseren Wänden auch nicht verbaut.