Hello!
I discovered that the carpenter placed the gypsum board joint over the plywood board joint on one of the bathroom walls right by the shower. The plywood is 15mm K20/70 900mm, gypsum board 900mm, studs 450cc. A waterproof membrane will be applied and then tiled. The plywood is screwed into the stud and the gypsum is screwed with screws going 15mm into the stud. Is it a problem to have joint over joint? (It's an old house from the 70s, so I assume the house/walls don't move as much as in new construction).
I discovered that the carpenter placed the gypsum board joint over the plywood board joint on one of the bathroom walls right by the shower. The plywood is 15mm K20/70 900mm, gypsum board 900mm, studs 450cc. A waterproof membrane will be applied and then tiled. The plywood is screwed into the stud and the gypsum is screwed with screws going 15mm into the stud. Is it a problem to have joint over joint? (It's an old house from the 70s, so I assume the house/walls don't move as much as in new construction).
Yes, that's probably best. However, the drywall seam ends up between the hot and cold pipe exit for the shower mixer if you lay the drywall in the other direction. Since the mixer should be mounted in the middle of a stud. Maybe not optimal either?Krille-72 said:
The plywood is secured with Chipboard screw 4.2x41mm FZB screw.
No general joints between plywood and gypsum. It's really not more complicated than that.G Graphite said:
"Since the mixer should sit centered on a stud"
I don't quite understand what the mixer has to do with plywood/gypsum?
If you've installed a nogging piece for a mixer as an extra precaution, then it's probably a horizontal stud? This stud isn't necessary but certainly not wrong.
If you mean you don't want a vertical gypsum joint between cold and hot in the shower, you can relax.
No general joints as mentioned. That's the most important thing.
Maybe ridiculous but still important to clarify what applies.G Gabbe1 said:
From Säker Vatten:
"Boards are screwed according to the manufacturer's installation instructions. When screwing plywood to steel studs, screws with release/free clearance should be used. Incorrect type of screw or screw sequence can cause buckling of the board against the stud."
The so-called "Wet Room Wall" is approved by all industry organizations involved in wet rooms. This means that no single industry dictates how the wall should be constructed.
The important part in the text above is actually the screw mentioned against steel studs. It’s the free clearance that is important and should apply even to wooden studs. Maybe there is a text about it on the manufacturers’ websites?
We have been using wood screws for a long time with sufficient clearance for wet room plywood. Many use chipboard screws but we believe the head is too small to ensure the board is truly pulled in against the stud.
As for both drywall and plywood being screwed into the stud, I say hmm.
If the plywood board is attached properly, then it is only for fire considerations that this matters.
Anyone with other information is welcome to teach me something new!
Nothing unusual. However, some are careless with noggins between the studs and let the plasterboard pull the plywood together. It becomes too weak even if it is framed 45cc.Viktor.J said:
But with some strips of plywood or whatever you have available, it turns out great!
Yes.G Graphite said:
Until you start screwing things. Then you need to have a noggin precisely everywhere something needs to be screwed.
In addition to 15 mm k Plyfa stabilizing the wall, the entire wall is seen as one large noggin where secure attachments can be made.
Sorry, poorly phrased question by me. I meant if it's okay with a wall where everything is according to safe water with 15mm plywood etc., but with the only difference being double layers of gypsum instead of one? For example, if you want to soundproof the bathroom or for fire protection.
