Can you use ship lap as flooring?

Hi Karen, here's a Hometalk post that you might find helpful.

https://www.hometalk.com/diy/floors-ceilings/laying-shiplap-floors-19215187

No reason why you can't. People have used plywood strips, wood boards, pallet wood, etc.

True shiplap. Shiplap, like tongue and groove, has a special rabbet or notch cut on the edges of the board. These rabbets allow the boards, when installed horizontally, to self-space themselves and keep water from getting behind them because they fit so perfectly.Shiplap is not plain wooden boards nailed on a wall. Often in old houses, these boards can be found on the exterior of the framing just beneath the siding.

Today, we frame a house and then install plywood sheathing to tighten the frame and help square everything up prior to putting on the siding and interior wall coverings. In the days before plywood, we used 1×6 or 1×8 boards, sometimes installed on a diagonal or horizontally as both sheathing and subfloor.

These boards can be salvaged and reused as paneling or other creative design uses since they can add a lot of rich character, but they are not shiplap.It’s Not Tongue & Groove

Sadly, it’s not this one either. Tongue and groove boards are used in all different places in old homes. Flooring is of course the most common, but there is a lot of siding that is tongue and groove as well.

Tongue and groove (or T&G as it is sometimes simplified) is just what it sounds. One side of the boards has a groove and the other side has a tongue. When they are installed side by side, they fit together nice and snug, which strengthens the floor or siding.

What Is Shiplap?

True shiplap

Shiplap, like tongue and groove, has a special rabbet or notch cut on the edges of the board. These rabbets allow the boards, when installed horizontally, to self-space themselves and keep water from getting behind them because they fit so perfectly.

Shiplap is mostly found in siding designs because of the need for consistent spacing and water tightness, but it can be found in other places. The lapped joint is one of the simplest you can use to accomplish the spacing and water stopping needs, which is why shiplap was and is so popular.

Once installed, shiplap can look just like regular wood boards because the rabbets are hidden, so yes, it can be hard to tell it apart from regular sheathing boards to the untrained eye, but it is different.

There are various profiles of siding available in shiplap too. Sometimes it’s just flat shiplap boards and other times you can find profiles like Novelty Drop, Dolly Varden, or the poorly named but still attractive #117 lap siding.

For the purist, shiplap is the original flat profile with a rabbet on top and bottom, but I guess if Mrs. Joanna Gaines keeps making us smile with her clever designs and trash talking of Chip, then we can let it slide that she calls a few more things shiplap than actually are shiplap.

As long as she doesn’t start proclaiming that they come from the shiplap tree, I’m still a fan.

If you are having trouble finding shiplap in your area, you can easily make your own shiplap with this quick tutorial. If you’re one of the lucky ones to have true shiplap in your house and you just need help repairing it, read my post The 7 Best Products to Patch Wood.