Hardwood flooring as countertop??

[Jeff Guerrero]

I'm looking to use leftover red oak flooring (unfinished, 5" wide) to create the counter/surface on top of built-in cabinets on either side of the fireplace. On top of the counter I'll build built-in shelves up the rest of the wall. Each counter will be ~30" wide x 20" deep and I want it to overhang (~1") the 2 cabinet faces that don't butt against a wall. I'll round over the overhang and I think just keep it the thickness of the wood (3/4") instead of adding faux thickness to the edges.

My questions:
1) How much should I consider expansion/contraction? I'd like to have the boards run along the width, and then rip some of the boards down for 4 mitered trim pieces around the outside. But will my miters just gap due to movement?

2) Suggestions on best way to fasten the boards? I could just create a panel and only glue the t&g so they're edge glued, then screw from underneath from inside the cabinet. Or I could put the whole panel onto some ply and glue to that surface as well. But then I'll have to consider hiding the ply underneath with faux thickness. I'm also not sure if I can glue the bottom faces of the wood or if expansion/contraction will buckle/gap the whole panel.

Really appreciate any thoughts!
Jeff

[John Lankers]

Welcome to the forum.
Not a counter top, but to give you an idea. When I built my current workbench 5 years ago I needed something heavy and tough but didn't want to break the bank so I glued up 3 layers of 1" MDF (24" x 72", glued and bradnailed left over 3/4" prefinished red oak flooring to it and then framed the whole slab with 2 1/2" x 6" red oak (handcut boxjoint corners) - it ain't going anywhere.
I think with a good substrate and stable humidity level (I assume dry near the fireplace) it might work. Engineered hardwood is being glued down on concrete floors even in basements and it works. It is all about the substrate and stable humidity levels. I used regular PVA glue, hardwood flooring glue would allow for minimal movement.
The alternative would be a floating slab with room for expansion around the perimeter - think tabletop.

[Robert Engel]

1) How much should I consider expansion/contraction? I'd like to have the boards run along the width, and then rip some of the boards down for 4 mitered trim pieces around the outside. But will my miters just gap due to movement?
I would expect up to 1/4" expansion/contraction in 30" but depends on climate & whether house is climate controlled. No way to predict, but miters always risk gapping in an application like this. A butt joint would be a surer way to go. I would expect minimal movement in a flooring board.


2) Suggestions on best way to fasten the boards? I could just create a panel and only glue the t&g so they're edge glued, then screw from underneath from inside the cabinet. Or I could put the whole panel onto some ply and glue to that surface as well. But then I'll have to consider hiding the ply underneath with faux thickness. I'm also not sure if I can glue the bottom faces of the wood or if expansion/contraction will buckle/gap the whole panel. Its thick enough so I would glue up like a panel.

[Jeff Guerrero]

Thanks for the thoughts! I think I'll glue up as a panel and risk the miters. I think they'll look better that way.

Jeff

[Brian Holcombe]

The reason why most floors do not have issues is that they're allowed to expand into each other. If you glue them all together they will expand as a whole panel, which is not good in a mitered frame. You could use breadboard ends instead and have a much more properly functioning table (so long as the breadboard ends are made to allow for wood movement.