Fitting laminate flooring around door frames is one of those jobs that separates a neat, professional finish from a frustrating one. The frame itself is not the problem — it is the expansion gap. Laminate is a floating floor, so it needs to move. If you cut the planks tight to the door frame, the floor will soon start to creak, lift or gap. The answer is to undercut the frame so the laminate slides underneath, leaving the required expansion gap hidden from view.

Why Door Frames Need Undercutting

Laminate flooring expands and contracts with changes in temperature and humidity. Most manufacturers ask for a gap of around 10mm at every wall and fixed object. Door frames, architraves and skirting boards are all fixed. If the laminate butts against them, it has nowhere to go. In a doorway, that pressure often shows up as raised edges or clicking joints.

Undercutting means cutting away the bottom of the door frame — the jamb and the architrave — so the laminate can pass underneath. The frame then acts as a bridge, hiding the expansion gap. It is a simple idea, but it needs a fine saw and a steady hand. Get it right and the floor looks as though it was laid before the frame was fitted.

Tools and Preparation

You do not need a workshop full of kit, but the right tools make the job clean and controlled. Gather these before you start:

• A fine-toothed saw — a Japanese-style pull saw or a flush-cut saw is ideal because it cuts on the pull stroke and leaves a neat edge.
• A scrap piece of laminate, plus a piece of underlay if you are using it. This is your height guide.
• A sharp knife or utility knife for scoring the frame.
• A pencil, masking tape and a vacuum or brush.
• Spacers, a tapping block and a pull bar for laying the floor.
• Scotia beading, a fine nail gun or panel pins, and a mitre box if you are fitting beading.

Acclimatise the laminate in the room for at least 48 hours before fitting. Check the subfloor is clean, dry and level. Any unevenness will show up as movement at the door frame, so sort it first.

Undercutting the Door Frame Step by Step

Start by protecting the surrounding area. If you are working over an existing floor, tape a piece of cardboard or hardboard against the wall to catch sawdust.

Place your offcut of laminate flat on the subfloor against the door frame. If you are using underlay, place a piece of underlay under the offcut so the guide matches the finished floor height. The saw will rest on top of this guide, so the cut sits just above the thickness of the floor.

Hold the saw flat against the offcut and begin cutting through the door jamb. Work slowly and let the saw do the work. Do not force it. Cut through the jamb and the architrave on both sides of the doorway. If the frame is painted, score the paint line first with a sharp knife to prevent it from splintering.

Once cut, remove the waste piece. Slide a scrap of laminate under the frame to test the clearance. It should slide in easily, with a small gap above it. If it catches, make another pass with the saw. Repeat on the other side.

Laying Laminate Under the Frame

When you reach the doorway, slide the plank under the undercut frame. Do not push it tight against the wall behind the frame. Leave the same 10mm expansion gap you have used around the rest of the room. The frame hides this gap, so it does not need to be pretty — it just needs to be there.

Use spacers against the wall and check the gap with a tape measure. If the doorway is wide, you may need to cut a plank lengthways so it fits neatly between the frame and the next row. Take your time with the measuring. A slightly loose plank is better than one that is forced.

If you are laying through two rooms, keep the expansion gap at the doorway and use a threshold bar or a T-bar to cover it. If the laminate runs continuously, the undercut frame is usually enough to hide the gap, provided the gap is not too wide.

Fitting Beading Neatly

Beading, often called scotia, covers the expansion gap along the skirting boards. It should be fixed to the skirting, never to the laminate. If you nail beading through the floor, you stop the floor from moving and create the very problem you are trying to avoid.

Cut the beading to length and mitre the corners. For a door frame, butt the beading neatly against the frame. If the frame is undercut, the beading can sit under the frame too, giving a continuous line. Use panel pins or a fine nail gun, and fill the nail holes with matching wood filler. A thin bead of flexible sealant along the top edge can hide small gaps, but avoid rigid caulk that might crack.

Getting the Details Right

Undercutting a door frame is not difficult, but it rewards patience. Cut too high and the frame looks hacked. Cut too low and the laminate will not slide under. Use a fine saw, take your time, and test with an offcut before you commit.

Remember the basics: leave a 10mm expansion gap, fix beading to the skirting, and never trap the floor. If you are unsure, practise on a piece of scrap timber first. A clean undercut and a neatly fitted bead will make the whole installation look deliberate and professional — exactly what you want when the job is done.