Door Frame Calculator
Here’s a comprehensive table for Woodworking Door Frame Sizing, covering essential dimensions, gap allowances, frame widths, and guidelines for building and installing door frames in woodworking projects.
| Measurement Type | Standard Dimension/Formula | Description & Use |
|---|---|---|
| Door Width | Measured across the door’s widest part | The exact width of the door; required to calculate frame width and ensure a proper fit within the frame. |
| Door Height | Measured from the top to the bottom of the door | Exact height of the door; required to calculate the frame height and ensure smooth operation. |
| Frame Width | 75–100 mm (standard); may vary | Typical frame width for residential doors. Adjust as needed for strength and aesthetic preferences. |
| Total Frame Width | Door width + (2 × (frame width + gap allowance)) | The total width of the frame; adds frame width and gaps on both sides to the door width. |
| Total Frame Height | Door height + (2 × (frame width + gap allowance)) | The total height of the frame; adds frame width and gaps on top and bottom of the door height. |
| Gap Allowance (Side) | 2–3 mm per side | A small gap on each side of the door to ensure smooth operation and prevent binding, especially with humidity changes. |
| Gap Allowance (Top/Bottom) | 2–3 mm | Top and bottom gaps allow the door to open and close smoothly without scraping against the frame. |
| Clearance from Floor | 10–15 mm | Provides a gap between the bottom of the door and the floor for clearance, particularly for carpet or rugs. |
| Hinge Spacing (Standard) | 7 inches from the top, 11 inches from the bottom | Standard placement for door hinges; ensures stability and balance for proper door operation. |
| Number of Hinges | 2 for doors under 80 inches; 3 for doors over 80 inches | Use two hinges for shorter doors and add a third hinge for taller or heavier doors to prevent warping. |
| Door Thickness | 35–45 mm (standard) | Standard door thickness; impacts hinge and hardware choices. |
| Rebate Width (for Rebated Frames) | 12–18 mm | The rebate (or lip) where the door sits within the frame; commonly 12–18 mm wide to accommodate most doors. |
| Materials | Solid wood, MDF, or engineered wood | Common frame materials; solid wood is durable, MDF and engineered wood are cost-effective alternatives. |
| Finish Allowance | 1–2 mm | Extra space in the frame to account for paint or finish, ensuring the door still fits after finishing. |
| Weather Stripping Allowance | 1–2 mm if applicable | Leave space for weather stripping if used, especially for exterior doors to improve insulation and sealing. |
Key Considerations for Woodworking Door Frames
- Total Frame Width and Height: The frame should be calculated by adding the door’s width and height plus the frame width and gap allowances on each side. For example, for a door width of 800 mm with a 75 mm frame and 3 mm gap allowance, the total frame width would be 800+2×(75+3)=956800 + 2 \times (75 + 3) = 956800+2×(75+3)=956 mm.
- Gap Allowances: Typically, a 2–3 mm gap is needed on each side, as well as at the top and bottom. This prevents the door from binding in the frame and allows for seasonal expansion.
- Frame Width: Common frame widths are between 75–100 mm, providing stability and a balanced appearance. Wider frames are often used for heavier doors.
- Clearance from Floor: Allow 10–15 mm of clearance at the bottom of the door to accommodate flooring changes, rugs, or carpeting.
- Hinge Placement and Quantity: Standard hinge placement is 7 inches from the top and 11 inches from the bottom. Use two hinges for doors under 80 inches and three hinges for taller doors to prevent warping.
- Material Selection: Choose solid wood for durability, or MDF and engineered wood for a more economical option.
- Finish and Weather Stripping Allowances: Account for an additional 1–2 mm of space for any finish or weather stripping to ensure a snug fit.
This table provides essential information and formulas to calculate door frame dimensions for custom woodworking projects, ensuring a proper fit, smooth operation, and aesthetic appeal.