How to Prepare a Bathroom for New Floor Installation

Nobody actually looks forward to installing a new bathroom floor. It’s not easy, and it’s not fun. Even if you have two and a half baths, putting one of them out of commission disrupts your normal routine. However, when the job is done, you’ll be much happier with the first room you see in the morning and the last one you visit at night.

view of small bath before and after construction

This bathroom project started out ugly, ended up pretty!

How do you know when it’s time to replace your floor?

Repairs and patches can only delay the inevitable. See our tips for deciding on a new floor to help you decide when to stop putting off this job.

Can you still use your bath while it’s under construction?

Sometimes, yes. In many cases, a cabinet-style vanity can stay in place. Same goes for the tub or shower. Your new floor can go up to these fixtures, rather than beneath them. On the other hand, the toilet has to go! We’ve seen installers leave the toilet in place. Bad decision; don’t do that. If necessary, you can remove and re-install the toilet at various phases of the project.

These things must go:

  • Toilet–replace shut-off if needed
  • Floor-based heat registers
  • Baseboard trim (most cases)
  • Old floor finish materials
  • Existing underlayment (usually)

You may be tempted to install a new floor directly over your old floor. Sometimes, this is perfectly acceptable. Those times are the exception. The best results always come when you start with your house’s original sub-floor and an empty room.

Please don’t try to save money by leaving wooden baseboard in place. Paintable wood trim isn’t expensive, and you’ll probably find that your new floor is better finished with a different product, anyway.

If your current floor uses a marble threshold, chances are about 50/50 that you can re-use it. Not all bathroom flooring needs a doorway threshold, though. We prefer Schluter™-type edges for many applications. Certain other flooring materials will call for specialty doorway moldings.

What’s the toughest part of the job?

Without question, removing your old bathroom floor is the least pleasant and most challenging part of the project. You’ll probably need knee-pads, work gloves, safety glasses, a dust mask, and tools like hammers and chisels. Basic vinyl floors usually come out easily, leaving hundreds of tiny staples behind. Mid-century concrete and tile floors present the biggest hurdle. Just finding a place to get leverage under those monstrosities can be difficult.

Be sure to protect other nearby flooring, like carpet or hardwood, from dirt and debris created during demolition. For extra-dusty tear-outs, use plastic sheeting to seal-off doorways. Work carefully to avoid damaging any fixtures you’ve left in place. Beware of sharp edges and rusty fasteners. Don’t try to carry out too much debris at once.

Add the right underlayment for your new floor.

New vinyl floors need plywood and flashing. Hardwood uses paper, and most laminates use foam padding. Ceramic and porcelain tile requires a heavy substrate–you have several choices for this. Before you install any new floor, always check the existing sub-floor for decay, excessive flex, and loose or squeaky sections. Repair as needed.

Preparation, preparation, preparation. There are no short-cuts to getting great results. When you do it right, you’ll only replace your bathroom floor once. See our related articles for information about floor design and installation.