Getting the corners right is the difference between a professional finish and a DIY look that nobody wants.
Mitre Joints
A mitre joint cuts both boards at 45° so they meet in the corner. It looks clean on internal corners in new builds where walls are perfectly square — but in older UK homes, walls are rarely true. If the corner isn't exactly 90°, a mitre will leave a visible gap.
Use mitre joints for: external corners (where the skirting wraps around a protruding wall). These are almost always mitred.
Scribe Joints
Scribing means running one board flat into the corner and cutting the second board to the profile of the first, so it overlaps it. The result is a joint that looks invisible even if the wall isn't square — and it won't open up over time as the timber moves.
Use scribe joints for: internal corners. Always. It's how professional joiners do it.
How to Scribe a Skirting Board
- Fix the first board flat into the corner.
- Cut the second board at 45° on a mitre saw — this reveals the profile.
- Use a coping saw or jigsaw to follow the profile line created by the mitre cut.
- Test the fit, pare back with a file or sandpaper if needed.
- Fix in place — the joint should sit flush with no gap.
Tips for MDF Skirting
MDF is dimensionally stable and less prone to movement than solid wood, which means mitre joints on internal corners are more forgiving than with timber. That said, scribing is still the preferred method for a long-lasting finish.
At Univers Skirting & Architrave, all our moisture-resistant MDF profiles are supplied at 3050mm lengths — long enough to run full walls in most rooms without joints.