Are you tired of constantly struggling to open or close your bilco doors? Are you worried about safety and security issues due to improperly functioning doors?

How to measure bilco doors accurately is essential to ensure a proper fit, whether you’re replacing existing doors or installing new ones. With the right tools and technique, you can take precise measurements to save time and prevent issues during installation. This guide will walk you through the key steps necessary to measure your bilco doors correctly, covering everything from assessing the dimensions of the opening to accounting for any irregularities in the surrounding structure.
Before starting, gather the required tools, such as a tape measure and notepad, and prepare the area for ease and safety during the measuring process.
What Are the Benefits of Accurate Measurements?
Taking accurate measurements for your bilco doors has several benefits. These include:
- Ensuring a Proper Fit: Properly fitting bilco doors provide better insulation, are easier to open and close, and can also improve the overall appearance of your home.
- Saving Time and Money: Accurate measurements prevent issues during installation that could lead to costly adjustments or replacements.
- Enhancing Safety and Security: Well-fitted doors reduce the risk of accidents and break-ins, providing peace of mind for you and your family.
What Will You Need?
To effectively measure your bilco doors makeover, you will require the following tools:
- Tape Measure: A tape measure is essential in taking precise measurements of the door opening.
- Notepad and Pen: A notepad and pen handy will allow you to record the measurements accurately for future reference.
- Ladder or Step Stool: Depending on the height of your bilco doors, a ladder or step stool may be necessary to reach and measure certain areas.
Once you have all the necessary tools, it’s time to start measuring!
10 Easy Steps on How to Measure Bilco Doors
Step 1: Measure the Width
To begin, open the bilco door fully to gain unobstructed access to the entire opening. Use your tape measure to determine the width of the door opening by measuring from one side to the other at the widest point. Ensure the tape measure is straight and taut to achieve an accurate measurement. Take note of this width in your notepad for future reference.

Repeat the measurement at least twice to confirm accuracy and rule out potential mistakes. Precision is key in ensuring that your replacement or new bilco doors fit correctly.
Step 2: Measure the Height
Next, measure the height of the bilco door opening. With the door fully open, position your tape measure vertically from the top edge of the opening down to the bottom edge where the door rests. Be sure to measure at the tallest point of the opening to capture the full height.
Like the width measurement, perform this step multiple times to verify accuracy and record the results in your notepad. Proper height measurements ensure the door’s functionality and compatibility with the opening.
Step 3: Measure the Depth
To complete your measurements, determine the depth of the bilco door’s frame or opening. Place your tape measure at the front edge of the opening and extend it straight back to the inner edge where the door meets the frame or floor. Ensure the tape measure remains level and does not sag during the measurement.
This step is essential, especially for doors with sloped or angled designs, as it ensures a precise fit. Write down the depth measurement in your notepad and double-check by measuring again to confirm accuracy. Accurate depth measurements are critical for proper installation and achieving a secure seal.
Step 4: Verify and Double-Check Measurements
Once all measurements—width, height, and depth—have been taken, it is essential to verify their accuracy before proceeding. Recheck each dimension by measuring again and comparing the results with your recorded values. Any discrepancies should be addressed by taking additional measurements to confirm the correct values.

Proper verification ensures the bilco door will fit perfectly within the opening, avoiding potential installation issues or future adjustments. Taking the time to double-check now will save time and effort later in the process.
Step 5: Prepare the Installation Opening
Before installing the bilco door, ensure that the opening is prepared correctly. Start by cleaning the area, removing any debris, dirt, or old materials that might interfere with the installation process. Check the surface for any irregularities such as cracks, unevenness, or damage. Repair and level the surface to create a smooth and stable foundation. A properly prepared opening will ensure the bilco door sits securely in place and operates efficiently over time.
Step 6: Position the Bilco Door
Carefully position the bilco door over the prepared opening. Ensure that it aligns properly with the edges of the foundation and sits evenly on the surface. Use a level to double-check that the door is correctly aligned both horizontally and vertically. Adjust the position as necessary to achieve proper alignment. Once satisfied with the placement, temporarily secure the door with clamps or braces to prevent movement during the fastening process. Adequate positioning at this stage is critical for smooth operation and a professional finish.
Step 7: Fasten the Bilco Door
Once the bilco door is appropriately positioned and securely held, begin fastening it to the foundation. Use the appropriate hardware, such as anchor bolts or screws, recommended by the manufacturer. Start at one end and work around, ensuring each fastener is tightened evenly to avoid shifting the door out of alignment.
Double-check that the door remains level and properly aligned as you secure it. This step ensures the door is firmly attached and ready for long-term use.
Step 8: Seal the Edges
After fastening the Bilco door, seal the edges where the door meets the foundation to prevent water infiltration and ensure a weather-tight installation. Use a high-quality exterior-grade caulk or sealant, applying it evenly along all seams and joints. Pay special attention to areas prone to water entry, such as the corners and gaps. Smooth the sealant with a caulking tool or your finger for a clean, professional appearance.
Allow the adhesive to cure according to the manufacturer’s instructions before continuing with any further steps. Proper sealing will protect the area beneath the door from moisture and improve the overall longevity of your installation.

Step 9: Test the Door
Once the sealant has cured, test the Bilco door to ensure it opens and closes smoothly. Inspect the hinges, handles, and latches to verify they function correctly. Open and close the door several times, checking for any misalignment or resistance. Make any necessary adjustments to ensure the door operates effortlessly. This final check ensures that your Bilco door is ready for regular use and provides a secure, weather-resistant entryway.
Step 10: Clean Up the Work Area
When the installation is complete, take some time to clean up the work area. Remove any leftover debris, tools, or unused materials from the site. Dispose of waste materials responsibly, following local recycling and disposal guidelines. Wipe down the installed Bilco door to remove dust, fingerprints, or excess sealant. A clean and tidy work area ensures a professional finish and allows you to admire the completed project without distractions.
By following these steps, you can confidently measure and install a Bilco door for your home or structure.
5 Things You Should Avoid
- Skipping Accurate Measurements: Avoid estimating dimensions or measuring roughly. Always use a reliable tape measure and ensure precision to prevent installation issues later.
- Ignoring Door Angles: Forgetting to account for the angle or slope of the bilco doors can lead to incorrect measurements. Be mindful of the overall structure and fit.
- Not Measuring Both Width and Height: Focusing only on one dimension, such as width, and ignoring the height can cause problems when selecting or installing new doors.
- Measuring the Exterior Only: Only measuring the frame’s outer edges without considering the interior dimensions might result in inaccurate results. Include all relevant parts for a proper fit.
- Failing to Double-Check Measurements: A single misstep in measurement can create costly mistakes. Always double-check your measurements to ensure they are correct.

What Type of Wood Should You Use for a Bilco Door?
When it comes to the type of wood to use for a Bilco door, several options are available. The most commonly used woods include pressure-treated pine, cedar, and redwood.
Pressure-treated pine is a popular choice due to its affordability and durability. This type of wood is treated with chemicals that make it resistant to rot, decay, and insect damage. It also protects against harsh weather conditions and can last many years with proper maintenance.
Cedar is another popular option for Bilco doors. It has natural oils that make it resistant to rot, moisture, and insect damage without chemical treatments. Cedar also has a beautiful appearance and is relatively easy to work with.
Redwood is another popular choice for its natural resistance to rot, decay, and insect damage. It also has a rich color and attractive grain pattern. However, it can be more expensive than other types of wood.
Ultimately, the type of wood you choose will depend on your budget, personal preference, and the climate in your area. No matter which type of wood you select, proper preparation and maintenance are essential to ensure the longevity of your Bilco door installation.
Conclusion
How to measure Bilco doors accurately is a crucial step to ensure a proper fit and functionality.
Start by measuring the width and height of the area where the doors will be installed. Use a tape measure to record the dimensions at the widest and tallest points to account for irregularities. Additionally, note the angle or pitch of the opening to ensure compatibility with the chosen door style. It’s also important to measure the depth of the areaway to verify the doors will fit without protruding awkwardly.
Carefully cross-check all measurements before purchasing a Bilco door to avoid installation challenges and ensure a secure, long-lasting fit.
About the Author
Adrian Green, a lifelong woodworking enthusiast, shares his passion for the craft through The Woodenify Blog. With a foundation built on years of hands-on experience in his father’s woodworking shop, Adrian is dedicated to helping others learn and grow in the world of DIY woodworking. His approach to woodworking combines creativity, practicality, and a deep appreciation for the art of building with your own hands. Through his blog, he inspires individuals of all skill levels to embark on their own woodworking journeys, creating beautiful, functional pieces of furniture and décor.
Professional Focus
- Specializes in DIY woodworking projects, from furniture to home décor.
- Provides step-by-step guides and practical tutorials for woodworkers of all skill levels.
- Dedicated to helping readers build confidence and skill through easy-to-follow instructions and tips.
- Passionate about fostering a community of makers who can share, learn, and grow together.
Education History
- University of Craft and Design – Bachelor of Fine Arts (BFA) in Woodworking and Furniture Design
- Woodworking Apprenticeships – Extensive hands-on training with skilled craftsmen to refine carpentry and furniture making techniques.
- Online Courses & Masterclasses – Continued education in advanced woodworking techniques, design principles, and specialized tools
Expertise:
- DIY woodworking, carpentry, furniture making, and home décor projects.
- Creating accessible tutorials and guides for beginner to advanced woodworkers.
- Sharing the joys and satisfaction of woodworking, from raw materials to finished products.