How To Seal Gaps Under Kitchen Cabinets

  • By: homeshacks
  • Date: March 22, 2023
  • Time to read: 7 min.
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Gaps under kitchen cabinets are not only unsightly, but they can also let in crumbs, spills, and rodents like mice or squirrels who like to make their nests there. Since you cannot always move your counters, here are some ways that you can seal the gaps with things around the house that you may already have.

1. Expanding Foam Sealant

To use this method, first, take a damp paper towel and wipe off the counter to remove dust, dirt, or oil so it will better adhere to the surface of the cabinet. Then follow these steps:

  • Get some canned expanding insulation foam from your local hardware store.
  • Squirt a bit out onto a plastic bag. Make sure that it is sturdy enough to contain the foam when you push the nozzle in.
  • Place one hand on each side of the gap and slowly press in along the length of the gap, stopping when you get near furniture or cabinets.

Note: The foam will expand by about 100 times its original size.

2. Rubber Cement

This method may not work as well as the expanding foam sealant, but it is much easier to use. You can find this item at office supply or stationery stores and some arts and crafts stores. Here’s how it works:

  • Make a small amount of rubber cement by stirring together white or yellow rubber cement and water.
  • Press the paste into the gap with a stick, paintbrush or any other suitable implement.
  • Use a damp paper towel to remove excess glue residue from the countertop and cabinet surfaces.

3. Spray-on Joint Compound (optional)

This method will also cover both the gap and the surface but it takes some time to dry. You may need to wait overnight before you can apply the paint. Follow these steps:

Thoroughly clean both the countertop and cabinet surfaces around the gap. Make sure there is no dirt or debris on either surface as this may clog up the nozzle and stop it from sealing properly.

Prepare a coat of joint compound by mixing it with water. You can buy this at your local hardware store and some arts and crafts stores.

  • Apply the paste around the gap and on both surfaces of the countertop and cabinet opening.
  • Let dry for about an hour then apply a second coat. (This will seal any cracks that may be in between.)
  • Wait until the next day then use your hand or a paintbrush to spread on the final coat.

5. Caulk Gun & Caulking

This method is probably the easiest, but it may be harder to find all of the materials you need for this option. However, if you have caulk at home, this is a good option for you. It is also the best method for larger gaps because it has a wider nozzle. For this job, you will need:

A caulking gun

Caulking – There are many different types of caulking so make sure you buy one that is suitable for your specific needs. If you have ceramic tiles or mosaic tiles on your countertop, make sure to buy acrylic caulk.

Caulking tape – this is optional but makes it easier to seal in gaps where the caulking may come out when you move your countertops.

  • Before starting, thoroughly clean both the countertop and cabinet surfaces around the gap. Make sure there is no dirt or debris on either surface as this may clog up the nozzle.
  • Hold the gun near the gap and slowly squeeze in a stream of caulk along the length of the gap, stopping when you have enough sealant.
  • Use a damp paper towel to remove any spills from around or on top of the countertop or cabinet surfaces.

6. Kitchen Counter Gap Repair Kits (optional)

There are many counter gap repair kits available at hardware stores. You can also find them online though there may be an additional shipping charge. These will usually include the following:

A caulking gun with a tube of sealant

Caulk tape – this is optional but makes it easier to seal in gaps where the caulking may come out when you move your countertops. Follow the same steps as for the caulking method above.

Why is there a gap under kitchen cabinets?

A common question I am asked is why there is a gap under kitchen cabinets. This has been puzzling homeowners for years, and the answer is more of a design decision than it is a defect. In fact, many cabinet manufacturers really don’t leave any gaps – but some that do may only have a slight gap at most, or none at all.

Most cabinet manufacturers leave an open space or gap under the toe kick (the piece of the cabinet that extends beyond the wall) to allow for ease of movement. This is usually about 1/4 to 3/8 inch space but varies by manufacturer.

Why do they do this? It allows you to easily sweep under your cabinets with a push broom to get all the dust and debris; it also allows you access behind the toe kick if you need to adjust or install wiring that is usually routed there.

What about the gap between the cabinets and the wall?

Many cabinet manufacturers do not leave a gap between cabinets and baseboard, as the wood expansion would create problems with gaps over time. The toe spaces are left open instead of trying to accommodate wood movement, which is often not possible. You may notice that cabinets and toe kicks in some areas do not have an expansion gap and yet the walls seem to be protected from gaps. This is because manufacturers use a different type of wood on the toe kick – such as poplar, which does not expand or contract as oak or maple would.

There are too many factors to consider when planning a home addition or renovation, and this is just one more example of why it’s a good idea to have your plans reviewed by a design specialist.

When you are planning your kitchen, think about the appliances that will be in the cabinets – such as an oven or microwave – before installing them. You don’t want to have to do any modifications or have to cut into your cabinets after installation.

How do I fill a large gap between cabinets and walls?

There are many ways to fill a large gap between cabinets and walls, depending on the material you choose. For example, if you used materials similar to your cabinets for the installation of new cabinet-to-wall face frames or filler strips, it is unlikely that the dark color of the wall will show through. To reduce shadow lines around each individual piece, cut or paint the filler so that it contrasts with the wall color.

For removable options, consider exchanging for adjustable shelving units instead of replacing the entire cabinet. Adding 3M command strips to each side of your cabinets can help keep them in place while you clean around them. Another option is to hang a piece of decorative fabric onto one or both sides of the cabinet.

For a more permanent solution, you can either paint or wallpaper over the wall behind your cabinets to create an illusion of depth and/or texture. Paint tends to be less expensive than wallpaper; however, it will require more frequent repainting as it chips away with high-traffic areas. Wallpaper is more permanent but also more expensive.

If you are looking to change the style of your cabinets without removing them, consider adding molding around the perimeter of your cabinet doors and face frames. This provides a clean finish around the edges while maintaining the open concept feel in your kitchen.


There are several options for you to choose from depending on your budget and personal taste. You can use wood filler, drywall mud, or joint compound to achieve the same effect.

  • Clean out any dust from the gap using a damp cloth and allow to dry
  • Place a small amount of wood filler into the gap ensuring that it is packed tightly into all of the corners before allowing to dry
  • After dry, you can use a fine grade of sandpaper and wet and dry paper to smooth down any roughness from the wood filler
  • When satisfied with the smoothness apply a layer of joint compound ensuring that it is feathered out to blend with the surrounding wall. Allow this to dry before repeating again and again until you are satisfied
  • Once the joint compound has dried to a hard crust, sand down any excess and paint. If required apply several coats of primer prior to painting. Allow your bookcase to blend in nicely with your wall.


As you can see, there are many ways to seal up gaps under kitchen cabinets no matter what kind of countertop you have. You can use one or more of the methods above to plug up those gaps so they are no longer a problem for you, and your kitchen area will look great as a result.

And don’t forget…you’ll save yourself money by not having to replace that broken countertop!

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