Filling the saw joints in my floor?

[Greg Urwiller]

The other thread on floor coatings reminded me to ask about this. I probably should put some kind of concrete floor coating on my shop floor....but before I do that, how should I fill the saw joints in my floor? They're about 2 inches deep, but they really don't pose (so far!) any problem, other than the fact that I have to spend a little more time to vacuum them out all the time. Any recommendations? Thanks. Greg

[Ole Anderson]

Sitkaflex SL self leveling sealer.

[Matt Meiser]

I was told silicone caulk is fine to. On mine, I put blue tape on either side of the cut, squirted it in, tooled it off and took off the tape so it looks neat.

[John A langley]

Boy are we picky! Clean them out to seal the floor. Either one of the two mentioned items will work well. Mine are filled with sawdust and that works well too.

[Howard Acheson]

I would just fill them with a caulk. But I would avoid silicone or anything that contains silicone. If you ever want to coat the floor with any type of finish, the silicone will cause you no end of trouble.

[David G Baker]

Even silicone won't stick to silicon after it has cured.

[Jason Steward]

My house is on a concrete slab, the best product I have found is a caulk called Big Stretch. It is not affected by moisture, and adheres well to concrete. It was recommended to me by a foundation contractor. It also adheres well between different substrates like wood and concrete. It takes a while to cure but remains flexible.

[Ole Anderson]

It is hard to get any kind of caulk very deep in an 1/8 inch sawcut, that is why a self levelling material works good as it will run into the joint. But squirting any kind of material out an 1/8" hole for 50 feet of joint is difficult, next time I will try a powered caulking gun. But I believe the Sika products are only available in the quart size tube, and I haven't found a reasonably priced power quart size caulking gun.

[Alan Bienlein]

WE always used NP-1 polyurethane caulk to caulk the joints and the control joints in concrete.

[Jason Roehl]

Because of the depth, I would tuck in some backer rod before using a polyurethane caulk. The backer rod (closed cell foam "worm") will keep the caulk in the correct cross-section--roughly an hourglass shape for maximum bonding on the sides and maximum flexibility in the center of the joint.

[Phil Thien]

I'd just leave the saw cuts, they don't look bad. Vac 'em out from time to time.

[Thom Porterfield]

Mine are filled with sawdust and that works well too.

+1

The floors in my house are heated concrete slabs. There are saw-cut control joints, but there are also cracks that decided take their own path of least resistance. I don't remember the name of it right off, but my friend the ceramic tile guy suggested I try this sanded grout stuff that comes in a tube like caulking. Several colors. Compatible with finishes (I wax the floors in the house). It's flexible, shrinks a bit, leaving a concave surface and can be put into cavities in layers. I got mine at the borg.

[Richard Jones]

Because of the depth, I would tuck in some backer rod before using a polyurethane caulk. The backer rod (closed cell foam "worm") will keep the caulk in the correct cross-section--roughly an hourglass shape for maximum bonding on the sides and maximum flexibility in the center of the joint.

WE always used NP-1 polyurethane caulk to caulk the joints and the control joints in concrete.

Ditto on both counts.

R

[Matt Day]

Whatever you decide make sure the filler material can move - in other words don't use grout or soething. Those saw cuts are called control joints, because they are supposed to control the cracking of the concrete.

[Michael N Taylor]

The only product we ever use in commercial construction is an epoxy caulk. Seal the concrete first then caulk the joints and take a scrapper of some kind and pull the caulk flat to the concrete before it sets up. You should be able to get all the escess of the sealed floor.