Recess in new concrete slab for curbless shower
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We’re pouring a full slab in our new walkout basement. I’m trying to plan a curbless shower in this bathroom and would like to minimize the transitions by recessing the concrete to receive the pre-fab shower pan (probably a Schluter pan).
I’ve looked on this forum, youtube, web search, etc. and can’t find anyone explaining how to form and finish a recessed area (This guy did at the edge of a slab, what I’m wanting to do 5 feet in, but doesn’t explain what he did https://www.youtube.com/watch?v=grwL9wICbPI ) There are lots of people cutting and chipping concrete after their slabs are poured or retrofitting a curbles shower which seems like a lot of work.
Does anyone have experience with recessing an area that’s not against an outside wall? Any methods, links, etc. would be appreciated.
I’ll be asking my concrete contractor, but I’m doing all the form work myself.
Thank you.
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Replies
Bryce,
By far the easiest way is to block out area to be recessed and pour it afterwards. It doesn't need the same level of finish as the rest of the slab so it's an easy DIY job you wouldn't need the concrete sub for.
Another option if you are using sub-slab foam is to frame the recessed area out of PT lumber and plywood.
The most common way this is typically formed is with pt 2"x6"s which stay in place after the two slabs are poured. I don't like that detail as it leaves an area that is subject to shrinkage between the two slabs.
Thank you Malcolm. Yes, I was overthinking it and trying to get it all done in one pour which is complicated (impossible?). The two step method seems more management for a novice like me.
No sub slab insulation (CZ 3 in North Alabama). So it will just be the top of the gravel and my vapor barrier. I'll have to patch that up and then fill with concrete.
Why don't you skip the pan and put down a liner and concrete shower base with tile, then you can go to any level you want and pitch it accordingly.
I'm going to try and do this concrete bit myself as well as the shower pan which I figured is more manageable with a pre-fab panel system. I was thinking Schluter but their stuff is expensive.
I should probably get a quote from a tile guy and if it's not bad then I could go your route and have them do it. The materials would be cheaper and would then just be paying their labor for a more traditional install.
Thank you for the alternate idea.