What is a Door Header Size and Why Should You Care?
The door header is a beam that spans the opening above doors. You should care because, without the proper door header size, your door could sag.
How to Calculate Door Header Size
- Determine the Maximum Span: This is the width of the opening you need the header for.
- Reference the Header Size Table:
| Header Size | Maximum Span |
|---|---|
| 4×4 | 4 feet |
| 4×6 | 6 feet |
| 4×8 | 8 feet |
| 4×10 | 10 feet |
| 4×12 | 12 feet |
- Select the Header Size based on the span measurement.
Calculation Example
For a 10-foot door span, you need a 4×10 header.
For a 9-foot span, go with the next highest option: 4×10 header.