So why am I posting a wood floor here?
This floor was done with salvaged 2 x 4 from our offices. We removed the wood/chipboard partitions and put in aluminum and glass.
Is that being a good steward of resources? Some other day we go into that.
So I bid on the wood from the old partitions and got a pickup load of 4x2 and chip board for $50.
I used my table saw and cut 2.5 cm strips and then put them on the floor. I nailed from the side and it is pretty tight. Now to plane and sand it smooth, fill the old nail holes. Even the walls I made of old lumber. The outside I had some 1 x 6 laying around.