How to fit coving & skirting
Difficulty rating: Medium
These tasks may be tricky so will suit you if you're experienced in DIY, or simply love a challenge.
Before you get started on any of our 'how to' guides, please take a moment to read through our DIY safety tips.
Measuring up for coving and skirting boards
- Measure the length of all the walls in the room to work out how much coving you need. Do the same for skirting but deduct the width of any doorways, cupboards and so on. To be safe, allow for 5% extra just in case.
Coving comes in a range of materials:
- Polystyrene: This is the least expensive but it does need a number of coats of paint. Polystyrene coving is also easily damaged so take care when handling.
- Paper-coated plaster: This coving is heavier and must also be painted. The smooth paper covering gives you the best base for painting.
- Plaster: Plaster coving is the most expensive but it has a brilliant white, smooth finish that needs less painting. You can also buy a wide range of authentic period plaster mouldings.
- Duropolymer: Duropolymer gives all the benefits of plaster coving but without the added weight. It's preprimed and comes in a choice of designs.
If your walls are slightly bowed, you can still add coving as styles are flexible enough to give slightly to match the wall. To hold coving in place, fix it to the walls with brass screws. Countersink the heads and fill the holes with filler.
How to fit coving
Coving can be a lovely feature for any room and here are some easy steps on how you get the best finish.
Fitting the coving
- Use a 100mm length of coving as a template to mark the top and bottom edges of the coving on the walls and ceiling of your room.
- Make the marks at regular intervals and join them together with a straight edge.
- Remove any loose wallpaper or flaky paint. Then score between the lines with a craft knife to give a key for the adhesive.
- Start on the longest wall and use a mitre block to cut the end of the first piece of coving at a 45-degree angle. Cut the coving with a fine-toothed saw and sand-smooth any rough edges. Using a mitre block to cut the coving for both internal and external corners will give you a perfect fit.
- With a filling knife, spread an even layer of coving adhesive over the back of the first piece of coving - i.e. the areas that will be in contact with the walls and ceiling.
- Hold the coving in place and line up the edges with the pencil guide lines on the wall and ceiling. Press gently along the whole length of the coving so the adhesive sticks evenly.
- To hold it firmly in place, support the bottom and top edges with a few galvanised nails. When the adhesive has dried, remove the nails and fill the holes.
- Use a damp paintbrush or sponge to remove any adhesive that oozes out from the top and bottom edges of the coving and to smooth the joint lines.
- Work around the room, butting the ends of the coving together where they join on straight sections of wall. You can use a little filler to smooth over the joins once you've finished.
Fix very heavy plaster coving with brass screws at 1m intervals. Hold the pieces in position and drill carefully through the coving and into the wall. Add wall plugs, spread on the adhesive and screw into place. Use filler to conceal the screw heads.
- Skirting boards obviously give you a decorative finish for your room. But they're also very useful for covering unsightly gaps caused by natural contraction. And they help reduce drafts too.
- Skirting is typically made of wood and comes in many decorative shapes (also known as mouldings). It can be varnished or painted.
- Before fitting your skirting, paint the back with wood preservative to extend its life.
When removing old skirting boards, tap the blade of a bolster chisel between the wall and the skirting with a hammer. Prise the skirting far enough to insert a crowbar. Using a thin piece of wood under the crowbar to protect the plaster, lever the skirting board away from the wall.
How to fit skirting boards
Like coving, skirting gives a lovely finish to any room and is really easy to fit when you know how. Here are some top tips.
1. The right type of fixing for your walls
- Any damp-proofed walls: Only use wood adhesive to fix skirting to where a wall has had a damp-proof course inserted. You don't want to drive nails or screws through the damp-proofing as this will damage the waterproof seal.
- Masonry walls: Use two masonry nails or two screws every 600mm. Try to use old fixing points if you're replacing the skirting. If you use screws, hold the skirting board against the wall and drill a pilot hole through the skirting into the wall. Then, countersink the screw holes, insert a rawl plug and fix with a screw. To hide the screw head use a little filler and sand it flush. Important! Check there are no pipes or cables behind the fixing points when using screws or nails.
- Stud walls: With a stud detector locate the studs in the wall. Use these as the fixing points - upright studs are usually 400mm or 600mm apart. Fix the skirting boards with two screws or two lost-head nails at each fixing point.
- Plaster walls: Try to find the studs and fix into these with either two screws or two lost-head nails. If you can't find the studs just fix at regular intervals.
2. Mitring corners for skirting
- The neatest way to fit skirting boards at internal and external corners is to use a mitre block.
- With a panel saw cut the end of the first piece of skirting at a 45-degree angle. Sand-smooth any rough edges.
- Fix the skirting with the method that suits your walls (see above).
- When joining two pieces of skirting at a corner, spread wood glue on cut ends. Hammer in two lost-head nails each side of the corner for extra strength.
3. Joining lengths of skirting
- If a single piece of skirting won't cover the whole length of a wall, you'll need to join two pieces.
- To join two lengths, mitre the ends of both pieces at 45 degrees - one mitre going one way, and the other the opposite way. Check the two pieces fit together before fixing them.
- Glue the cut ends of the two boards and fix them to the wall next to the join with lost-head nails.
4. Finishing off the skirting
- Fill the gaps between the skirting and the wall with decorators caulk and leave it to dry.
- If you're painting the skirting, fill all the screw and nail heads and then sand them flush.
- Apply knotting solution to any knots and then paint on a primer. Next you'll need an undercoat and finally a topcoat of paint.
- If you're varnishing the boards, use an acrylic filler that matches the colour of the wood. Apply the varnish according to the manufacturer's instructions.
Try to make as few joins as possible on the walls. It's worth buying an extra full-length piece of coving or skirting board rather than use up two shorter sections. It will look much neater.