Shower curb
 

First tiling project. I need a higher shower curb than usual. My plan is to use 2 2x6s on end capped with hardibacker and wrapped with Kerdi. Is this acceptable?

Welcome to the forum, Brian! :wave:

Initially, I’m hesitant. Is this over a wood subfloor or slab? How were you intending to fasten the “on edge” 2x to the floor? And would you have an objection to building up the exact same size, but with 2x (or ply) material laid flat to the floor and stacked to your desired height?

:)

No objections, it’s just that I already have the 2x6s, and they’re the length that I need. My thought was to use a high strength construction adhesive to fasten curb to the subfloor. The more I think about it, though, the more it would make sense to build up with 2x4s

Edit: it is wood subfloor

Assuming it's a wood-framed subfloor, I think you could probably screw them together, toe-screw them into the subfloor, and screw them in at both ends.

But doing it the way Kurt talked about would be the sturdiest.

I’m more concerned about expansion and contraction of the 2x6 “on edge” vs. the same overall curb dimension if it was made with flat stacks of 2x. The Hardibacker will insulate the brittle tile on top of it from a certain amount of wood movement below it, but I’m concerned that the movement will be beyond its limit.

Wood is hygroscopic and will forever expand and contract with changes to its relative moisture environment. It expands and contracts at a rate twice tangentially around the growth rings vs. from the pith of the tree outward. So, most (sans what most folks call quarter-sawn or rift-sawn lumber) 2x will expand and contract in the direction of its width by twice that of its thickness. So, if you wanted a taller curb, I’d prefer flat stacks of 2x or plywood...or better yet masonry or foam.

:)

Great info. Thank you!

Hi all, :)

I'm not sure the nature (wood or concrete) of the subfloor was ever determined here. If by chance it is concrete, a wood curb should not be used. It should instead be made from bricks or concrete blocks or portions thereof.