I’m laying 3/4″ bloodwood in my home office, about 140 sq ft. My floor is concrete so I’ve layed a 5/8″ plywood subfloor. The bloodwood is so hard that nails have split some of the tongues. Given this problem, I’d like to predrill and countersink for trim head screws. My concern is that no one includes screwing down a hardwood floor as an option. Is that because it will take a month of Sundays or because it’s a bad idea?
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This may not be a great deal of comfort, but at least one other person has thought about doing this. :o) My guess is that the time is the argument against.
Normally, screwing it down is done from the face with wider boards than as a hidden fastener. Other than the tiome involved, I see no problem with what you are thinking off. Be sure the screws have a smooth shank for the portion in the flooring strips. In other words there will be threads holding in the subfloor but smooth in the flooring strop.That way there is some alowance for wood movement with the seasons and from traffic.
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How will you cover the trimhead screws? Putty? won't look good. Standard size plugs are too big. You may have to make your own unless you screw thru the tongue.
I don't think people are real high on exposed screw heads on a finished floor. Also installation time, as well as going back to plug all those holes is gonna cost more in time, aggravation, etc.
You gonna plug, or leave the heads exposed? You mention countersinking, not counterboring. Be a shame to have screw heads mar the surface of that wood...
Why would there be any holes or screw heads showing? AZ says he's getting tongues splitting when he nails the stuff, so wouldn't you assume he's going to drill and countersink for screws through the tongues instead of nails? It was Piffin who mentioned screwing through the face.
Too true.
I never met a tool I didn't like!
I have set up a jig to guide a countersink and counterbore through the tongue at 50 degrees - no exposed heads in my floor! :-)
The counterboring was tough, I had to increase the diameter by 1/8" in my test piece of wood over what I'd normally use with a #6 screw because the wood is so hard.
What Kind of nailer are you using? My Porta-Nailer's nails are thin enough that they seldom split the tougue in even the most brittle wood.....
I installed about 100 SF of t&g fir on an exterior porch using stainless trim screws thru the tongues, after predrilling each hole. Worked fine, took less than a day to cut and install all of it.
Did you put a vapor barrier under the plywood you installed on the 'crete?
When I'm ready to go, I'll put 2 layers of 6 mil paper paper under the ply and a layer of tar paper between the ply and the wood.
Forgive a dumb question from a homeowner. Are you using nails or staples? If the former, might staples split the wood less?