How to fill a large gap between a floor and baseboard

by May 2, 2021Cleaning

Living in an old house can be an exciting adventure. But with old houses comes new problems, and some are easier to fix than others.

A common problem with old homes and even new homes is a large gap between floors and baseboard on the walls.

How to fill a large gap between a floor and baseboard

This hole can be a source of drafts and prevent your home HVAC system from becoming as efficient as possible. Because of this, you will want to close this hole and make sure it stays sealed all year round.

In this article, we have gathered some methods to fill a large gap between a baseboard and floor. Any of these approaches will do the job and keep your home air tight when the weather gets cold.

Filling a gap between a base plate and a floor: Basic idea

The correct method of filling a gap between the baseboard and the floor depends on the size and location of the space.

Some of the ways to get this space sealed include:

  • Fill the hole with caulk
  • Use of flexible trim strips

How much of a hole can be accepted?

how much gap is acceptable

When building a home, there will always be some variation in how things are done. This is one of the things that makes home ownership unique and interesting.

However, gaps between floors and baseboards can be the result of poor workmanship. If the holes are large, you will want to fill them in to get a cleaner and more modern look.

Whether or not you fill in these gaps is up to you. If they are large enough to let in cold air or are particularly noticeable, it may be a good idea.

Add a floorboard

If the distance is due to the floor not reaching the base plate, this can be remedied by adding a new floorboard.

Trim a floorboard to the desired width that hides under the base plate. If the base plate is low enough, you should be able to completely seal the hole.

You may not have access to the original flooring materials that your home was built with. Since this is a trim piece that does not carry the load, you can use thinner floor pieces if you need to.

If your floor is heavy and grooved, you need to be able to snap the new floorboard into place. If not, attach it to the floor joists yourself.

Once the new floorboards are in place, the gap must be sealed or small enough to keep cold air out.

Add shoe molding

add shoe molding

If the distance between floors and baseboards is due to the baseboard being too high, there is another solution. Shoe molding is an L-shaped trim piece that is designed to cover holes like this one.

If the space you work in already has molding, you need to be able to find a style that fits.

Cut and measure the shoe shape, and secure it with finished nails. Then you can paint it to match the walls for a hassle-free fit.

Fill the hole with caulk

Shoe shaping may not fit into the particular style of your home. If you want to maintain a modern, contemporary look, it’s a good option to fill the hole with caulk.

Choose a waterproof, latex caulk that can be painted for this job. This will ensure that it seals the gap and makes it airtight to keep the heat inside.

Apply caulk sparingly with just enough to cover the space. Then use a spatula to level it and make a flush joint that matches the wall.

Be sure to mask the floor when applying caulk to prevent it from staining the floorboards.

Use trim strips

Trim strips are self-adhesive, silicone-based strips that are designed to fit perfectly in trim holes.

They are a perfect solution if you do not want to risk damaging your baseboards or floors with paint or caulk. They fit in the holes and seal with their adhesive backing.

Simply cut the trim strips to the right length and apply them on the gap. They fold between the floor and the base plates and form a tight seal that is as effective as sealant.

Trim strips come in many colors so you are sure to find some that match the paint on your wall.


frequently asked questions about how to fill the gap between the base plate and the floor

  • How high should the bottom plates be from the floor?
Related post  15 ways to clean your home and get organized

If you plan to install carpet, your baseboards should be approx. 1 inch from the floor. This gives you enough space for upholstery and rugs.

If you leave the floors without carpets, do not have any holes. The distance should not exceed about a quarter to prevent heavy pulling.

  • Is it okay to fill in for old moisture?

For the most part, it’s okay to put new caulk over old caulk. However, you must remove it if there is not enough space for the new sealant to escape.

Also remove the old caulk if it rots away or is also water damaged. This will ensure that you get a tight seal with the new sealant.

  • What is the best paint for baseboards?

Semi-gloss paint is ideal for base plate. It is durable and helps protect the base plates from damage.

The bottom plates are an area of ​​high touch that sees a lot of bangs and bumps. Using a high-quality semi-gloss paint gives a long-lasting finish.


Efficiency and style are incredibly important considerations for homeowners. By sealing any holes or openings, you can keep your home environmentally friendly and warm in the winter.

Sealing the holes in your floorboards also gives your home a finished, polished look. Small details count in interior design and this is an easy problem to remedy.

Skip to content