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Hi there. I’m looking for advice or help to secure this walnut to a concrete slab floor. I need to allow it to expand and contract with the humidity of the shower in this bathroom. I will be using something like a silicone caulk where the wood borders the stone and mortar around it. I’m just not sure how i should secure it to the floor though. Any advice would be appreciated. It is currently 6/4 thickness. Thanks!
There are adhesive's made specifically for gluing wood flooring to Concrete. Some of them have built-in moisture barriers that are formed when the glue is applied. Check with a local flooring contractor. I I know our flooring contractors use them for glue down wood flooring over concrete but I do not know of a specific brand offhand.
that said this seems like a dangerous installation outside of a shower with a high probability of issues down the road.
Very interesting idea! I'll be interested to see what answers come about and some photos of the final execution.
The only way way I would consider executing this kind of design would be "entombing" the entire floor in epoxy resin and making it a giant solid. Similar to making a large rectangular table with a live edge slab. multiple pours would be in order for a project this deep.
please keep this updated with your progress and decisions along the way!
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If I had to do this, I would cut the trunk and branches into smaller, and narrower pieces so that it ends up being more of a mosaic. Then I would use a wide, silicone grout between the pieces.
While, as Harold says, it's a very interesting idea, I would lean toward what Prashun says to cut the wood into smaller pieces because such an organic material as wood will tend to change shape according to humidity and the season. That said, wood is predictable in that it expands and contracts much more across the grain than along the grain. Accordingly, you would probably be safe to cut the pieces long and narrow. I think pieces could be cut as long as 18" ~ 24" and as narrow as 3" ~ 5".
This is all dependent on the "grout" you plan to use. If you use stone, it is pretty inflexible and even smaller pieces may show cracks between the grout and the wood in dry weather and may buckle in humid times, while using something like epoxy (as Harold suggests) or, say, Bondo, may be more forgiving.
I would say experimentation is in order but, wood movement experiments would be quite long term and your timing needs may not work.
I have all of that figured out to allow for expansion and contraction. I was looking for ideas to secure the wood to the concrete floor. I am using spar varnish on the bottom and have decided to screw the sections down with tapcons.
Screwing down with tap cons is a bad idea. They will not allow for movement you will likely have cracking or buckling for both around the screwed area as moisture affects the material. The screws only provide local attachment. They will hold the local area secure during movement but not the surrounding area. The glue is both slightly flexible but will also provide total adhesion. If you are sealing the material you should seal it with the same sealer all the way around. You want even moisture protection.
Thanks for the advice. I figure it would be no different than attaching breadboard ends when building a table...tightening the screws down but drilling oval-shaped holes in the boards to allow wiggle room for the boards to move from side to side. Adhesive on the other hand, i just can’t picture that going well with movement. Maybe I’m wrong and that a flexible adhesive against the concrete floor may be the way to go, but one thing i really won’t to avoid is finding out one or more of the boards broke free and is floating. Then comes the silicone caulk against the edges of the wood separating from either the wood or the mortar, the mortar chipping away, etc. if i screw them down and my method of allowing for movement with humidity changes doesn’t go as planned, I can deal with a little splitting if the rest of the floor will stay intact. The boards are already a little checked after drying them out in my attic after the first planing.
I welcome more advice disagreeing with my plan. I feel like I have all things considered now, but certainly would change my plan if i am convinced. Thanks!