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  • Writer's pictureMalcolm Petit

How to Measure for New Internal Doors

Are you in the market for new internal doors for your home? From oak doors to wooden doors, the options are endless. However, one crucial aspect that often gets overlooked is getting the right measurements. To ensure a perfect fit and a hassle-free installation, it's essential to learn how to measure for new internal doors. In this guide, we'll walk you through the process step by step, ensuring that you have all the information you need for your carpentry project.

Why Accurate Measurements Matter

Before diving into the measuring process, let's understand why precise measurements are so crucial. Overestimating or underestimating the size of your internal doors can lead to several issues, including difficulty opening and closing the door, draughts, and noise infiltration. To avoid these problems, follow our comprehensive guide to measuring your internal doors correctly.

Step 1: Measuring Door Height

To measure the height of your internal door, you'll need a tape measure, a pencil, and a piece of paper. Here's how to do it:

Measure the inside of the vertical sides of the door frame. Keep in mind that not all frames are symmetrical, so measure both sides. Start with the left side, measuring from the top corner to the bottom corner, then repeat in the middle and on the right side.

The longest length you obtain from these measurements will be your required door height. Be sure to account for any floor coverings, as they can impact the door's height.

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Step 2: Measuring Door Width

Just like with height, doors are not always the same width throughout, so it's essential to measure accurately. Here's how to measure door width:

Measure at three different points inside the door frame: top, middle, and bottom. Starting at the top corner, measure across, then repeat this process in the middle and at the bottom.

Use the widest of these measurements to determine the width of your new door.

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Step 3: Measuring Door Thickness

Measuring the thickness of your existing door is relatively straightforward, as most internal doors have standard thickness. Here's how to do it:

Measure the door's thickness at handle height. In most cases, the standard thickness is 35mm for internal doors. However, it's worth noting that some rooms, like kitchens and garages, may require thicker fire doors, which can be either 40mm or 44mm.

To understand the thickness that your frame can accommodate, measure the frame rebate where the door sits when it's closed.

Additional Tips for Measuring Your Internal Doors

To ensure a proper fit and a smooth installation, consider these tips:

  • Double-check all measurements before making a purchase.

  • If you're fitting new frames, make adjustments to accommodate standard door sizes and avoid the need for bespoke doors.

  • Take into account how the floor might affect the ease of door opening, especially if it's uneven on either side.

  • Consider any finishing touches, such as hinges and handles, when measuring for your new doors.

  • Standard Sizes for Internal Doors

While there isn't a single standard size for all internal doors, most fall within a specific range of sizes. Common internal door sizes include 1981 x 762 x 35mm, but they can vary. For a more detailed breakdown of standard sizes, you can refer to our internal door size guide.

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Measuring for Doors: Frame vs. Existing Door

There's often confusion regarding whether to measure based on the existing door or the frame. We recommend measuring based on the door frame to ensure a flush fit with the frame, which your current door might not provide.

Understanding Door Size Terminology

Door sizes can be confusing, with measurements given in industry terms that may not be familiar to everyone. For instance, you might hear about a "30 68" door, which translates to 30 inches wide by 6 feet 8 inches tall. In the UK, doors are usually measured in millimeters. When shopping, you'll see door sizes presented as Height (mm) x Width (mm) x Depth (mm), like 1981 x 762 x 35. Our internal door sizing guide can help you convert between metric and imperial measurements.

What is a Rough Opening?

You might come across the term 'rough opening' when shopping for doors. It refers to the approximate size of your doorway, including both the door and the frame. Typically, it's calculated by adding between two and two and a half inches (50-64mm) to the size of the door.

How Much Smaller Should a Door be Than the Frame?

When hanging a new door in an existing frame, it's essential to achieve the right fit. Most doors come with generous lipping, allowing you to plane them down for a perfect fit. Ideally, there should be a gap of around 3mm (⅛ of an inch) at the top and sides and around 9mm (⅜ of an inch) at the bottom for easy opening and closing without compromising insulation.

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In conclusion, measuring for new internal doors is a critical step in ensuring a successful carpentry project. By following this comprehensive guide and considering all the factors involved, you can save time, money, and avoid potential installation headaches. Don't hesitate to contact us if you have any questions or need further assistance in selecting the perfect doors for your home. Happy measuring and carpentry!

At Malcolm Made This, I am not just passionate about providing you with top-quality doors; I am also committed to making your carpentry dreams a reality. Whether you need assistance trimming your doors or have other wooden visions in mind, I'm here to help.

To learn more about how Malcolm Made This can bring your carpentry projects to life, please don't hesitate to reach out. Fill out our contact form, and I will be delighted to assist you every step of the way. Your vision, my craftsmanship – together, we can create something extraordinary.

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