A complete guide to lay floorboards. Replacing part or all of a wooden floor is a big job which must be done with care, but even so, it is certainly a job that most people can attempt themselves. Assuming the joists are sound, laying floorboards is really all about planning, careful cutting and taking your time to make sure each board is fitted properly before moving on to the next. This guide will look at the methods involved in laying both square-edged and tongue-and-groove floorboards. You can find out guide to replacing individual floorboards here.
Preparing the Room
If the house is not a new build and has skirting boards in place, remove them all before you start. Skirting boards always sit above the wooden floor. You cannot just buy the boards and start work the same day or you are just storing up problems for the future. Lay the boards in the room that is being boarded for two or three days. This lets the wood acclimatise and will help to stop the boards bending and warping in the future.
If the room is currently completely unboarded, lay thick sheets of chipboard down across the joists to create a safe working platform.
Laying Square-Edged Boards
Laying the First Row
Lay the first board across the floor joists, starting in the corner of the room. There needs to be a 10mm gap between the edge of the boards and the wall, so cut some 10mm wedges from scrap wood and use these to maintain this gap all the way along the board.
When the board is in the correct position, start to nail it in place. Use two nails at each point the board passes over a joist. Position the nails centrally on the joist and about 25mm in from the edge of the board. When the board is nailed all the way along its length, go back and use a nail punch to make sure the nail heads are below the surface of the wood. If you do this now, as you fix each board, you are less likely to miss a nail than if you try to do them all once the floor is laid.
If your new floorboards are not long enough to stretch the full length of the room, you will need to make sure that the end of a board is sitting on top of a joist. If you need to trim the boards so that they do this, do so before you nail them down. The end face of the board should be exactly over the middle of a joist. When you cut a length of board to fill the shortfall, make sure you take into account the 10mm gap needed at the wall. The end of the infill board should butt up against the full board, sitting on top of a joist.
It is a good idea to alternate the boards so that you do not end up with a single long joint running across the room. This will not only look better, but will also result in a stronger floor.
Clamping the Floorboards
Now that you have the first row in place, you can either continue to lay rows by pushing each up against the previous row and nailing it into place, or you can use the clamping method. This involves laying the next four or five boards loosely, and then using a Floor Clamp to push them together and ensure a tight joint between the boards. You can hire Floor Clamps fairly cheaply.
An alternative way to ensure a tight joint between the boards id to use a pair of wedges. To do this, cut a short length of waste floorboard (about 200mm long) and then cut this in half diagonally. Lay the next four boards loosely, leave a gap the same width as a board and then temporarily fix a board to the joists. Lay the two wedges into the gap so that they look like a single piece of board and then use two hammers to knock the wedges together. This will act to press the four loose boards together and ensure a tight joint between them. You can then nail down all four boards and repeat the process over the remainder of the floor.
Finishing the Floor
Unless you are very lucky, it is quite likely that the last row of floorboards will need to be cut down to fit in the gap between the penultimate board and the wall. Measure the gap and take 10mm off the total measurement to allow for the gap at the wall. Cut a floorboard to fit and lay it with the uncut face against the last board (the cut edge facing the wall). You won’t have room to clamp the last board in place, but you should be able to get a tight joint by using the 10mm wedges you cut earlier to maintain the wall gap.
Nail the final board in place and remove all of the wedges around the edge of the room. It is a good idea to let the floor settle for a day or two before you start to fix skirting boards around the walls.
Laying Tongue-and-Groove Floorboards
The method used for laying tongue-and-groove floorboards is similar to that used in laying square-edged boards. The main difference is that the boards can also be fixed by driving nails through the tongue of the board (known as secret nailing), thereby hiding it from view when the floor is finished.
Secret Nailing Tongue-and-Groove Floorboards
Place the first row of boards as detailed above, laying them so that the tongue of the board is facing towards you. Place the point of a nail at the point where the tongue joins the vertical face of the board and drive it into the joist below at a 45 degree angle. You must then use a nail punch to make sure the head of the nail is below the surface of the wood. If you do not do this, the nail head could stop the groove of the next board sliding over the tongue of this one.
Position joints above joists, just as you would when using square-edged boards, and finish the floor off in the same way. If you do not want to bother with secret nailing, simply follow the clamping and nailing technique described above for square-edged floorboards.