Ok, so I’m sure you’ve been asked this question a million times and I know that you are supposed to install new wood flooring over old wood flooring in the opposite direction but I have what seems to be a unique situation. My 4" heart pine floors have been sanded down too far in some key high traffic areas and some of the tops of the grooves are breaking off. Also my floors are also subfloor as well as finish in the second story of my house. So my question is: Can I install a nail down floor in the same direction as my old floor if I purchase 6 to 8" planks? Its going to look awfully funny if I have to go in the opposite direction (i.e. hallways, stair landings etc).

Since your existing pine floors also serve as subfloors and they have been sanded so many times that you are down to the T&G (almost), I suggest installing a layer of plywood over these floors first, then go over that with whatever you wish. Since the T&G is breaking in areas, the old pine floors will continue to get worse and the structural integrity of those floors could be comprimised. A layer of 1/2" CDX plywood, well screwed and glued, will salvage your subflooring and you will be able to install new floors over that in the same direction as the pine flooring.

Thanks Gary. I do have to tie into a magnesite staircase so are there any other options since I will be 1" (1/2" ply and 1/2" flooring) above the staircase? Are there any other extremely thin but stout underlayments in existance? The sub/finish floor is still about 5/8 + with minimal deflection. I do notice slight deflection when my father roams about upstairs but he is 300 +.

UPDATE:

The problem areas are where the floor was reversed and groove is to groove, with no spline present. This is the only location so maybe the problem isn’t as bad as I thought. The floors are actually in beautiful shape overall so is there a repair I could do given that its also the subfloor?

I would take the old floor up and start over. Using the old floor as the sub floor is just cutting corners in my book. It you want the job done right, and don't want your ceiling to start getting closer to your head take the old wood up, check the subfloor install new moisture barier and and nail the new wood down. I can assure you that method is going to be full proof, as for the other you never really know.
Just my 2 cents.

Edited By Administration: Welcome to the forums Blaine but please refer to our terms of service(TOS) Thanks!

we are not talking strip plank flooring here. My floors are upstairs and the subfloors happen to be the actual finish floor. So my interior and exterior walls happen to be on top of the floor in question. Not taking them out unless you want to help?

Always love to help.

I understand what you have, even though Blaine doesn't seem to. How thick are these pine floors upstairs? 1&1/2"? 3/4"? Are the joists/beams supporting the pine floors exposed from below so when you view your first floor ceiling, you are looking at the beams and the bottoms of the pine floors? Or you could just have an older pine subfloor, nailed over joists with either sheetrock or lath and plaster ceilings. Either way, the CORRECT way to do this is to install the 1/2" plywood. This is per the NWFA and NOFMA. Now if you don't want to do it the correct way, that's fine. Have it your way. I'm just telling you how to do it so you won't have problems down the road. The transition to your stairs isn't a problem. You simply install the stair nosing along with the rest of the flooring. The first step down maybe a little tall, but it wouldv'e been anyway laying a new floor over your pine. It's either this or lay the new flooring perpendicular or horizontally to the existing. Your choice.

Geez! Just install it diagonally.

What a dumb mistake! I mean't to say DIAGONALLY, not horizontally! Thanks Chuck, for mentioning the correct direction.

P.S. Glad you're back!

I thought you were advising that it be installed on the floor.

I like doing things the right way. That is why i am even coming to this forum. If it was a slam dunk easy project then I wouldnt be consulting you guys. So a magnesite staircase, lets just call it a "stone staircase", cannot and will not accept any staircase nosing. So maybe we are now getting the magnitude of the project. I am not going to use a 1" transition strip from a top stair to top of new floor + CDX. Was hoping beyond all hope that someone would have a trick solution to the problem. I guess I will just install the new floor perpendicular to the old floor. As for diagonal installation - I dont own a modern house - I own an Arts and Crafts Tudor style. I will not sacrifice the style of the home.

Gary, adding a 3/4" tread/nosing to the top stair would be a violation of building code, and I know you don't mean to do that.

OK guys, look here. Lets take this one "step" at a time.
1) You have an existing floor/subfloor on the second story with a "stone" staircase. How is the transition made now? Is there a wood nosing that is flush to the existing floor and overhangs a stone riser? I'm trying to get a picture of this wood to stone transition.
2) IF there is a wood nosing, you simply cut it back flush to the stone riser OR remove it and install some wood of the same thickness that DOES NOT overhang the riser.
3) Now, at this point, you can:
a) install some plywood to strengthen the existing subfloor and then
install your new flooring paralell to the existing flooring OR;
b) install new flooring running perpendicular or diagonally to existing
wood floor/subfloor
4) At the staircase/step transition, you simply install a new stair nosing that sits on top of the existing floor and is FLUSH with the new floor and overhangs the riser. Quite simple really.
Now if the issue is that the rise at this transition will be too great, then there is NOTHING that can be done EXCEPT to remove the existing flooring OR rebuild the stairs.
5) If, at the top of the stairs, there is now some sort of stone nosing, you can either attempt to remove it and re-install it at the new level OR have another one fabricated.

The only "code" issue would be the rise from the last stone step up to the wood floor on the second level. Since I don't know what the actual measurements are, I don't know if there would, in fact, be any code violation. Assuming that the rise NOW is exactly the same from the bottom step to the top, the ONLY way he could add a new floor without removing the existing floor and still be within stair code is to install a 3/8" thick floor OR thinner (5/16") and not use any plywood underlayment. You may have up to a 3/8" variance on the rise.

OK, school's over. Now go out and play!

Gary you're almost right. If he installs 5/16 - 3/8" flooring to only the second floor (the top step), then it's ok. But if he installes new flooring to the first and second floor, the code is violated and the black helicopters will be circling his house any minute.