There are many ways to build a shower niche and I have used just about every method under the sun to make one. First off these shower niches for the most part fall outside of Industry Guidelines. Where they usually stray are at the back side of the niche where they are either part of the opposite rooms drywall or worse part of an exterior wall.
I'd like to showcase this particular shower niche's build because it showcases a lot of basics that people should understand when building one from scratch.
One of my rules when building a shower niche is to oversize them somewhat so I can fine tune the final tile position once more of the tile setting has been completed. When you oversize a niche you will in the end need to fill in this void or space with something. Using regular thin-set is not going to cut it since it is allowed to be used up to 1/4" thick. And this is not so thick.
Here is a play by play of this shower's niche. I build the walls out of Denshield, the framing is a combo of steel studs and 1/2" plywood strapping. The waterproofing product is Ardex 8+9 (a cementitious waterproofing product).
Rule number one: The Layout
The layout should be perfect. After all it is a custom niche so it should be custom. We charge a pretty penny for building these and we deliver exactly what looks best or exactly what the client has requested.
A tile niche should be centered on grout joints or centered on a wall. They should align with the other joints joints and when possible the tile should seamlessly fold in and out of the shower niche. This niche is centered on the short wall above the Tub's waste and overflow. Many times a tubs waste and overflow is used as a fixed reference point. If you have not installed the tub as yet and need to get framing done. Consider oversizing the studs against this back wall - it is easier to infill later than move things around after.
This niche will measure 30cm x 30cm exactly (+/- 1 mm) - The tile is 30cm x 60cm (1'x2' roughly).
Here is a peak at step one in action.
After the layout on day one we set the back tile and the two vertical side pieces. These sides where set a hair lower since the niche will have a sloped bottom to allow water to drain away.
Heading to work.... Will add the remaining pictures and posts this week as the niche takes shape.