Back to Flooring Replacement Checklist
Transitions PhaseStep 29 of 32
Cut Doors
Trim interior doors so they swing freely over the new flooring without dragging.
Quick Summary
Measure the gap needed for new floor height, mark each door, and cut with a circular saw. Most doors need 1/4 to 1/2 inch clearance above the finished floor.
When Door Cutting Is Needed
- New flooring is thicker than old flooring
- Underlayment added height to the floor
- Doors were already tight against old flooring
- Carpet replaced with hard surface (usually adds height)
Measuring for the Cut
- Place a flooring sample on the subfloor at the door location
- Add underlayment thickness if not already installed
- Mark the new floor height on the door jamb
- Add 1/4 to 1/2 inch for clearance gap
- Transfer this measurement to the door bottom
Pro Tip
Use a piece of new flooring as a marking guide. Set it on the subfloor, add a coin or washer for clearance, and trace the line onto the door.
Cutting the Door
Step 1: Mark the Cut Line
- Use a straightedge to draw a line across the door
- Apply painter's tape along both sides of the cut line
- This prevents chipping and tear-out
Step 2: Set Up for Cutting
- Lay door flat on sawhorses
- Support near the cut to prevent sagging
- Clamp a straightedge as a saw guide
- Cut from the side that will be less visible
Step 3: Make the Cut
- Use a circular saw with a fine-tooth blade (40+ teeth)
- Set blade depth just through the door thickness
- Cut slowly and steadily along the guide
- Do not force the saw - let it cut at its own pace
Hollow Core Doors
Most interior doors are hollow core. You can usually cut up to 1 inch from the bottom. For larger cuts, you may expose the hollow center and need to reinsert the bottom rail.
Finishing the Cut Edge
- Sand the cut edge smooth with 120-grit sandpaper
- Seal the edge with paint or clear finish
- This prevents moisture absorption
- Allow finish to dry before reinstalling
Reinstalling the Door
- Match doors to their labeled locations
- Align hinges and insert pins (or attach screws)
- Test that door swings freely without touching floor
- Adjust strike plate if latch no longer aligns
Special Situations
- Solid wood doors: Can cut more, but may need to refinish entire door
- Fire-rated doors: Consult manufacturer - cutting may void rating
- Bifold doors: Cut each panel the same amount
- Door too short: May need door sweep to close gap