Subfloor questions

Q: I have a couple of subfloor questions for you. I have removed the old wood floor from the first floor of our home. Our sublfloor is 4 wide X 3/4 thick planks run diagonally across the joists. The planks have gaps between them of about ¼ to ½.

I have been screwing the planks down to quiet the floor and I understand that I next need to install some sort of sheet material on top of the planks before the hardwood floor can be installed. What type of sheet material (plywood, osb, thickness?) do you recommend?

Also, I have read that I should put down rosin or felt paper on top of the sheet (plywood) before installing the wood floor. What purpose does this serve? Should I also put this on top of the original diagonal plank subfloor before installing the plywood?

Also, should I remove the baseboard trim before doing all this or can I leave it installed?

After installing the new subfloor I am thinking about hiring a pro to do the floor install. It is a 350 square foot area. Prefinished. Would you like to give me a quote?

A: I have found that screws driven through these old sub floors into the joists often causes splitting. So I generally spike the old sub floor first. If that has not been your experience, thumbs up to you.:) I would screw down 3/8 spruce sheeting, again into the joists. Best to mark on the base or wall where the joists are, then drop chalk lines on top of the plywood. this will give you a good solid sub floor, which really is the point of the exercise. Nothing like putting down a new floor and having it squeak all over the place! If you find there are still occasional areas that squeak you can pull that sheet up, apply some urethane adhesive and screw it back down. While installing plywood sheeting over the existing sub floor is not often absolutely essential, it does provide a more solid and smoother surface to build on.

Being an older home, you likely have higher baseboards, 7″ or better. You don’t need to remove these, and doing so may impact your plaster walls. If it was smaller base, say 3-4″, it would have to come off, since there would be little showing after installing 1 1/8 of additional flooring and then quarter round.

The flooring paper assists in sliding the boards into place, and also as a moisture retarder. This is used between the sub floor and hardwood floor only.

While I do install pre finished flooring, I always give my recommendation to a site finished floor. There are a number of reasons for this. No, a site finished floor is not a match to one that is finished by machines and other specialized equipment in a factory, where they apply multiple coats of aluminum oxide coatings along with UV blockers with specialized equipment. This is a very tough finish. No doubt about it. However, this actually becomes a problem down the road when the finish finally starts to look tired and shabby and needs a re coat. At that point, reality takes a left turn. If you can’t sufficiently abrade or scratch the existing coating, you won’t gain adhesion for the next coat of finish. Aluminium oxide coatings are designed to resist abrasion. At this point, the bevelled edges also come into play. they would have to be dealt with also to try and get another coat of finish to stick. The point of the bevel is to hide the fact that these floors are not flat, from one board to the next. That creates another issue in trying to abrade a floor like this. So, in reality, you would be looking at a complete re sand, and not just a light buff and coat to freshen up the look. A site finished floor offers unlimited choice of colours if you want it stained. The look and coating applied on such a square edge floor gives a uniform flow, since there are no bevelled edges to separate each board. This is also better at resisting spills, since the coatings are across the entire floor, joints and all and not just applied to each individual board.

Pre finished, if it is a good quality product, is more convenient initially, but in my opinion poses more issues in the long term than what it is worth. Given a cost comparison between the 2, if you are looking at one of the better products, such as Mirage which is about twice the cost of unfinished flooring, the 2 types of floors come out near the same total cost in the end.

I (note: these are OLD/outdated prices!) charge $3.00 sq. ft. to install prefinished, and $2.25 for unfinished. (My site: Sanding, staining and finishing with 3 coats is $3.25, and natural is $2.35 sq. ft. I have recently had opportunity to use a different type of finish on several jobs that I am now offering as an alternative to urethane top coats. It is a penetrating tung oil finish which offers good protection to wear and tear, excellent water resistance and great ease at care and refreshing the finish.