Measuring the opening correctly is the crucial first step when planning to install an internal bifold door, ensuring a proper fit and smooth operation.
Here's how to measure the opening where your internal bifold door will be installed:
1. Measure the Height
To determine the necessary height for your bifold door, you need to measure the vertical distance within the door frame.
- Step One: Take your measurement from the sub-floor to the lintel above the opening. The "sub-floor" is the base floor layer, not necessarily the finished flooring. The "lintel" is the horizontal beam or support directly above the door opening.
- Step Two: Taking three vertical measurements – from the left, right, and centre of the opening – will reveal whether you have a crooked opening. It's essential to note the smallest measurement if the height varies, as this will dictate the maximum door height you can accommodate.
2. Measure the Width
Just like height, the width of the opening needs to be measured accurately at multiple points to account for any irregularities.
- Measure the width across the opening at the top, middle, and bottom.
- Note the smallest measurement. This is the critical dimension for determining the maximum width of your bifold door system.
3. Check for Squareness
The process of taking multiple measurements for both height and width helps you identify if the opening is perfectly square or if it's "crooked" (out of square).
- As mentioned in the reference, measuring height at the left, centre, and right clearly shows any vertical variation.
- Similarly, measuring width at the top, middle, and bottom reveals horizontal variations.
Why is this important? Bifold doors require precise alignment to fold and slide smoothly. If your opening is significantly out of square, you may need to consider adjusting the frame before installation or selecting a door system that allows for some tolerance.
Summary of Measurements
It's helpful to record your measurements clearly. You should have at least six measurements in total:
| Measurement Type | Location | Value (e.g., mm) | Notes (e.g., Smallest) |
|---|---|---|---|
| Height | Left Side | ||
| Height | Centre | ||
| Height | Right Side | Smallest Height | |
| Width | Top | ||
| Width | Middle | ||
| Width | Bottom | Smallest Width |
Use the smallest recorded height and width measurements to determine the correct size requirements when ordering or selecting your internal bifold door system. Remember that door manufacturers usually recommend a small clearance gap around the door for ease of installation and operation. Always check the manufacturer's specific measuring guide and recommended tolerances.
