I just reinstalled our couch (on top of new cork flooring) and used a
hex head screw designed for installing metal roofs. They are double hot
dipped galvanized, have a neoprene washer (which on a barn roof seals
the penetration but in other applications acts as a lock washer) and
best of all they have a 1/4" hex head that can be driven with a nut
driver. These are virtually impossible to strip and very easy to drive
in awkward places. They can even be driven with a socket wrench in a
pinch. Only downside is they stick up ~ 3/16" above the floor, but
under the couch and most cabinet locations that's not an issue.
Available at farm supply (lots of those here in WI) and may building
centers in a variety of lengths.
My second choice, for lower profile applications, is a torx style drive
pan head. Easier to drive and harder to strip than square drive.
Chris K.
1979 Int'l
#8638