How to Install Filler Strips Between Kitchen Cabinets

Installing filler strips between your kitchen cabinets can be a tedious process. They’re usually included with the package of your cabinet, but they’re not often the exact size to fit your kitchen. Since kitchens are seldom alike in size, dimensions, and design, installing cabinet filler strips will require some handy work to make it fit.

So how can filler strips be installed between kitchen cabinets? You may either have upper cabinets or base cabinets, but the process is typically the same. First, you’ll need to measure the gaps between cabinets and the wall or the gap between an adjacent cabinet if you have a corner cabinet. Cut the filler strips to match your measurements. Once you're confident with the size, slide it between the gaps to attach it.

Materials You’ll Need Before Installing Your Filler Strips

• Tape Measure. Cabinet manufacturers will usually package in filler strips that you can use. These are essentially pieces of wood that come in a general size. This means that they’re seldom the exact size that you need to fill in the gap in your kitchen. That’s why the tape measure is an essential tool that you’ll be needing to know the ideal size of the filler strip. 
• Belt Sander. Simply sawing the filler piece may result in jagged edges or wood on the sides. It’s better to slowly sand down to the size that you need rather than risk over cutting the filler piece. The belt sander tool is also perfect for smoothing out the sides of the filler piece to make the fit even more snug.
• Pencil. A simple pencil should suffice to mark the areas of your filler piece that you need to cut. If you have access to it, you can also use a scribing tool to get even more accurate markings with your measurements.
• Saw (Straight or Circular). The saw that you're confident and comfortable in using should work. If you have access to it, you can use a circular saw with a tooth blade to make your cuts cleaner and more accurate but a straight saw should suffice too.
• Cardboard. A fairly inexpensive item that you’ll need to trace around the cabinet fillers to act as a template. 
• Wood Glue or Silicone. Having these will ensure that the strip is securely attached. Though a snug cut of the filler strip might pass without needing to use any adhesive, it would still be preferable to use it, especially for jobs involving upper cabinets. 
• Optional: Drywall Screws, Drill, Drill Bits, and 4 Small Wood Blocks. For a more secure fit, you can also screw the filler strip onto the cabinet frame itself. This will require more tools however. It’s recommended that the drill bits that you use are a similar size to the screw shaft. The wooden blocks should be at least the same thickness or a few inches thicker than the filler strip; its length should be equal to the trip's width.
• Optional: Step Ladder. If you are dealing with upper cabinets, you may need the aid of a step ladder to reach where you intend to install cabinet filler strips. 

Safety Precautions to Remember

The tools used for this job are not to be handled lightly, especially the saw, belt sander, and drill if you intend to use them. Always be careful when using these tools to avoid any risks to your health. Always wear safety goggles and gloves while operating these tools. Always keep children and household pets away from the area that you will be working in. For additional safety, ask someone you trust to help you or spot you for support if you're climbing a step ladder. 

If you have little to no experience operating these tools, and you see this as an advanced project, it’s highly advised that you contact a professional to do it for you. Here at Zothex Flooring, we take your safety seriously. We will be your partner in designing custom kitchen cabinets that fit your home only. Contact us and let us know if you are interested in styling your kitchen together. 

1. Measure the Gap Between Your Kitchen Cabinets Thrice

Why thrice? Cutting the filler strips is irreversible, which is why you want to make absolutely sure that your measurements are accurate. It is also because spaces between cabinets or walls are seldom the same. 

Gaps between kitchen cabinets are not universal in measurement. Take measurements of the gap from the top, middle, bottom of the cabinet to the wall or the neighboring cabinet. There are occurrences where sections of cabinet are inconsistent or you have uneven walls or an uneven floor in your kitchen; the cabinet bottom may be closer to the wall or adjoining cabinets than the top or your kitchen floor may slope downwards. 

Also measure the height of your cabinet box or cabinet doors to know the exact size to cut the filler strip. You ideally want the cabinet filler strip widths and height to be the exact size or slightly larger to keep it forced between the gaps once you've installed them.

2. Cut the Cardboard to Test Your Measurements

After you have found the measurements, cut a piece of cardboard to match the exact size. Then, place it in the gap to see how accurate your measurements were. You can use a simple utility knife to cut the edges of the cardboard that you feel is too wide or tall. Measure, test, and refine until you are confident with your measurements. 

3. Trace the Cardboard on a Filler Strip then Saw 

Once you have found the appropriate measurements, place the cardboard onto the strip of wood that is the gap filler. Trace around the cardboard and be prepared to saw, but don’t go at it just yet. Try to make your cut a few inches wide at first, and do this especially if you don't have access to an accurate circular saw. 

4. Sand The Sides until It Reaches a Snug Fit

You’ll need to repeat the process that you did with the initial cardboard sizing: measure, test, and refine. Use the belt sander to refine the edges of the strip until it's reached a snug fit in the gap between cabinets or the wall. 

5. Attach the Filler Strip

Spread the wood glue or silicone along the side of the filler strip. Then attach the strip diagonally. First place the glued side of the strip along near the cabinet, then push the other side until it aligns flush with your cabinet or a few inches within the gap, depending on your preference. 

Alternative Method Using Screws and a Drill

This method should be performed with the advice of someone who has had experience installing filler strips; you will be drilling through the cabinet's frame. Drilling holes through your cabinet will be irreversible. 

First, remove the doors of the kitchen cabinet to make it easier for you. Then, place the small wooden blocks outside of the cabinet frame, flush with the front, behind where the hinges are attached. Align the blocks to where the hinges are screwed and pencil a mark below it; you will be drilling through the frame to attach a screw through this block. 

Attach small blocks of wood to the back of the filler strip itself. To ensure that it is secure, counter-drill through the block until halfway through the filler strip, to avoid the sharp point of the screw poking out from the other side. Then drill in the screws to firmly attach the blocks.

Then drill a screw through the cabinet frame at the area that you marked previously. Afterwards, reattach the cabinet door.

Should attaching filler strips between your kitchen wall cabinets be too labor intensive for you, it is recommended to contact professional services such as Zothex Flooring.

Design Custom Fit Kitchen Cabinets with Zothex Flooring

We design custom cabinets that will fit your kitchen nicely. We have a wide selection of cabinet styles and designs, including frameless cabinets and framed cabinets of the wood type of your choosing. If you're still feeling unsure about which cabinet is right for you and your kitchen, you don't need to worry. We offer FREE consultations with our experienced designers to guide you. Contact us through our website to learn more. 

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