What To Do With Wood Board After Leveling the Floor?

[jaykchan]

In one of the "Ask This Old House" TV show, Tom helped a guy to level a concrete floor which was not even in this way:

- Find a 2x4 wood board that is straight.

- Put the 2x4 on top of the highest spot of the floor.

- Level the 2x4.

- Scribe on the 2x4 to transfer the ups and downs of the floor on the

2x4.

- Use a power tool to cut the 2x4 along the scribed line.

- Put the 2x4 back on the floor to exactly where it was. This time the

2x4 should be flat on the floor with its top side becomes level.

- Do the same thing on another 2x4 and put it parallel to the first

2x4. (I guess the distance between them depending on how large the floor is). These two 2x4 form a dam.

- Pour leveling compound into the dam.

- Put another straight wood over those two 2x4, and squeeze the leveling compound in order to level it.

I really like this technique. My question is: What should we do with those two 2x4? Should we leave them on the floor? Should we remove them when the leveling compound is stiff enough? I would assume we want to remove them. But the problem is that if we remove them, we would lose the level surface when we try to level the area adjacent to the first area. But if we don't remove them, I am afraid that they may become rotten.

Any idea?

Jay Chan

[tbasc]

The surface of the newly placed leveling compound can take the place of the 2x4. A new 2x4 will have to be scribed at the far edge of the next pour. TB

[Gina and Les Armstrong]

IIRC, they glued and nailed the forms/dams to the existing floor. I assumed they used P/T lumber for the forms/dams.

[jaykchan]

This makes sense. This means that we will need to do a very good job in leveling and smoothing the surface of the first area. Otherwise, any unevenness in the first area will show itself in the adjacent second area. This is probably still OK if we are going to put ceramic tiles over the area.

Thanks for the info.

Jay Chan

[jaykchan]

Really. Somehow, I didn't remember that they did that. You are probably right. They needed to have a way to secure the woods in place before they could pour the leveling compound into the dam; otherwise, the leveling compound would burst the dam. Now, I think about this; I seem to vaguely recall that they really glue the wood onto the floor.

But I seem to remember that the wood didn't have the greenish pressure treated wood look. The wood just like a regular wood.

Jay Chan

[Gina and Les Armstrong]

Check this link.

The description is brief, but it says that the boards were fastened to the floor after scribing and cutting.

Les

[jaykchan]

Yes, you are right. Tom indeed fastened the wood shrims on the concrete floor. As I mentioned in my last post, I vaguely recalled that Tom used adhensive to glue the wood shrims. I "seemed" to recall that he said the adhensive was marine-grade and very high quality or something.

I surely hope that those wood shrims can withstand moisture because that concrete floor is either right at the ground level or slightly below grade.

Jay Chan