Build a Wood and Slate Basket-Weave Floor: Border and Fastening
Trim the floor square and build the border before gluing and screwing the entire assembly to the subfloor
I’m going to straight edge the edges. If I need to trim this at all, I’ll take a circular saw and cut it to perfection. There was just enough variation in my joints that there are a few long boards and a few short ones.
I know I need to cut this. It’s going to make my life a lot easier if it’s nice and flat. So I’m going to pull the woven boards out of the way; sweep the floor and mark where my radiant heating is under the subfloor; put construction adhesive on the back of the boards; and then screw the assembly in place and finish the installation.
I’m using a Kreg jig. It allows me to drill at a steep angle along the edge of the board where you can’t see it, and it also guide the screw at that same angle. Because the jig is meant to slide along the edge of continuous decking or flooring, it is a little wider than the openings in our basket weave. We had to trim a few guide tabs off of the jig to fit our application.
In practice, you just register the tabs against the edge of the board; use the drill bit that comes with the jig to drill a hole; drop in a special screw with a head that is just big enough to fit into the jig; and then drive the screw until it’s tight.
I’m laying out my plug holes in the ends of the boards because I have to screw the whole thing down so it’s flat before I cut it. Because I have radiant-heat tubing down below, I need to be really careful about the depth that I drive these screws. So I’m using a countersink bit with a stop collar, and I’ve kept my screws to 1-in. length to be sure I don’t go any deeper than 1-1/4 in.
Next, I’ll use my Festool circular saw and guide rail to make perfect cuts along the ends of the woven boards. Then I’ll cut the border boards to length, pocket screw the entire border together, and screw and glue it to the subfloor around the weave.
I cut a bunch of plugs from various scraps of the pine to match the different colored boards. Then I match the plugs to the color and grain of the various holes, glue them in, and chisel and plane them flush.
The trick when sanding the entire floor is that there’s a whole lot of character and figure in this heart pine, so you don’t want to take this down to bare, perfect joinery and smooth wood. You want to take it down to where it’s reasonably smooth along the joints and leave all the character you can.