I sawed some 1/2" thick boards on the saw mill that I installed between the joists. These boards are only there to hold the insulation, so they won't carry a lot of weight.
The insulation was added (6"), and a plastic membrane was mounted on top. I am not quite sure that it is needed since there will not be much human activity in the barn to breathe out humidity, and besides it also shields the insulation a bit while I am working on the floor itself.
The floor boards are 1 3/4" thick and are joined by means of a loose tongue.
I have finally gotten around to using my Veritas BU jointer that I bought some years ago at a great price. I use it to joint the edges of the boards before I make the groove for the tongue.
The upper corner is planed off with two swipes of the block plane, so it is just a tiny bevel that will keep splintering to a minimum.
The groove is made with an electric router. A year ago I finally had it with my old router and forked out some real cash and got myself a more professional Makita router. That thing is so much better than the old one, it is easier to hold, it can actually retain the cutter in the desired position and it does a quick job of making a groove.
Due to the width of the boards I am installing them with nails through the top instead of using hidden nails or screws.
I would have liked to use headless nails like I used for the porch, but those are not available in 5.5" so that is why I am using regular nails. They look a bit crude, but it is a barn after all.
They are mounted 5/4" form the sides of each board, and if the board is very wide I also put a nail in the middle as well. To keep the heads aligned, I am using a piece of string to mark out the position.
Olav stopped by today and gave me a hand, and also took some pictures. So all the pictures of today are by the courtesy of Olav.
Floor boards on the right, Merlin half way hidden.
Veritas BU jointer with fence, now in use!
The board is clamped to a 5x5 to be able to stand on an edge.
Beveling the edges of the groove.
Larch floor board prior to grooving.
Grooving with the Makita.
A router is noisy and dusty but fast.
Merlin is supervising the project.
A finished board with grooves.