Skirting board tutorial – scribed and external mitre joints you need to know

The joins you NEED to know for tackling corners are all in this skirting board tutorial

piece of skirting clamped into a wooden DIY mitre box

Background to this skirting board tutorial…If you follow me on Instagram, you’ll know that I recently started a big bedroom makeover on a budget and one of the first things to go were the manky old skirting boards. I’m a big fan of tall boards and found these great value ones at Wickes which came ready primed and beautifully sculpted (ok that sounded weird, but never underestimate the difference a beaut new bit of skirting will make to a wall, or in fact room).

Ripping off the old ones was satisfying (I wrote a ‘how to’ for Real Homes which you can read here if you are interested…)but not nearly as satisfying as fitting the new ones.

Lots of people had questions about how I’d done the internal and external corners so I thought I’d pop a quick skirting board tutorial post out with some top tips.

The correct way to tackle corners

When fitting new skirting boards, at some point you are going to need to go round a corner. This might be an internal corner an external corner, or both. If you have a mitre saw that’s great, but if you are here reading this and looking for advice, it’s more likely that you have a mitre box and a handsaw. If your skirting boards are too tall for your mitre box then read my ‘how to’ on making a DIY mitre box to the exact height you need…

External Mitre Join

For going round an external corner you should cut two 45-degree angled cuts and join as shown below…

two pieces of skirting board lined up in an external corner shape

Scribed Internal Join

For internal corners, you might be tempted to do the opposite of the above join and cut two 45-degree angled cuts to create a right-angle join, but this only works if your walls are perfectly straight and plumb. As walls are often slightly out, it’s better to create the below type of ‘scribed’ internal join. You stick one piece of skirting to the wall without cutting the end on any angle (ie so the end is a straight cut that goes flush to the wall) and then you scribe out the shape of the second piece of skirting so that it fits into the first piece perfectly.

a piece of white primed skirting board cut at 45-degree angle laying on the floor.

The easiest way to scribe the join is to cut a 45-degree angle first, as this will show you the profile of the decorative detailing…

A scribed piece of skirting board lined up against another

Then, use a coping saw to cut along the edge of the profile so it looks like the piece in the image…

Then you can butt the scribed piece up to the piece you stuck to the wall and it should fit perfectly even if the join meets at an angle that is slightly off from 90 degrees.

How to hide the joins in the skirting board

Now you know how and where to cut them, the final piece of the puzzle is to hide all your hard work & smooth those joins so it looks like one continuous piece of skirting board beauty. This is the easy bit and by far the most satisfying if you ask me. Simply fill the gaps with decorators caulk, wipe any excess, allow to dry, then sand to create a smooth finish and prime and paint… et voila!

Read my must-have DIY tools post to find out all the other toolbox essentials I recommend.

Thanks so much for reading. I’d love to keep you up to date with future DIY, decorating, interior styling, and upcycling projects, if you would like to receive my (not more than weekly & no spamming I promise) emails, then please subscribe (scroll down to the box at the bottom of the page).

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