If you’re looking for an eco-friendly flooring option which not only looks good but is versatile, warm and hard-wearing, look no further than recycled floorboards. By using floorboards that have been re-milled from old wood such as beams, or have been floorboards in an old house that has been demolished, you’ll be saving new trees from being cut down, plus you’ll probably get more interesting and more resilient wood and you’ll be gaining a floor imbued with age, character and history. If you can use a hammer and saw, installing floorboards is not as hard as it sounds.
Put the recycled floorboards into the room where you are going to install them and leave for at least a week to acclimatise. The boards may shrink or expand depending on the temperature and moisture content of the room. During this time, remove any old nails or other hardware from the recycled boards. Check for splinters and remove or sand down.
Prepare the subfloor. If laying over joists, check they are all sound. If laying over a solid wood subfloor or a concrete subfloor, it is best to cover it with a layer of builder’s felt or red rosin paper. If the concrete is damp, you may need to install a damp-proofing membrane.
Measure the room to check it is square. If not, you will have to lay the floorboards to account for this "unsquare-ness" by tapering the boards at one or both sides of the room. Remove the floor trim moulding by levering out carefully with a wide chisel. Mark a starting line 1/4 inch out from the straightest wall. This is the expansion gap and allows the boards to expand and contract. It will usually be covered by the moulding when replaced.
Lay the first board along the starting line and nail in place. If tongue-and-grooved floorboards, lay with grooved edge facing the wall. If laying over joists, boards must be perpendicualr to the joists and nailed at the joist lines and all joints must be over joists. If laying over a solid subfloor, stagger the boards to prevent creating lines across the room.
Nail the next board at the end of the first board and continue until you reach the end wall. Remember to leave the expansion gap at the end wall.
Lay several rows of flooring (without nailing) to check for warped boards, defects and colour patterns. This is called “racking” the floor. Arrange boards to create the best combination of grain and colour. Nail each board in place, from end wall to end wall. Ensure boards fit together snugly by tapping into place using a block of wood or by using a flooring jack which holds the boards together as you nail them.
Cut the last lengths of board to fit the final space, remembering to allow for the expansion gap.
Finish by sanding and staining if necessary and revamping the boards with a protective finish such as varnish, polyurethane, wax or oil. Replace the trim moulding.
If laying your floorboards over joists, the boards need to be at least 3/4 inch thick to support the weight. If laying boards over a solid subfloor, boards need only be 3/8 inch thick. If nailing floorboards over joists, all joints must be over the joists otherwise the floorboards will sag and creak. Tongue-and-groove boards can be “secret-nailed” by driving nails into the tongue at 45 degree angles and setting the nails home with a nail set so they don’t interfere with the interlocking of the tongue and groove. First and last boards will need to be surface nailed. Lay out the boards before nailing, as recycled flooring can have all sorts of bends and bows and defects. Avoid using old nail holes as nails may work loose more easily.
Always wear protective clothing when working with power tools and when handling wood: tough gloves (to avoid splinters), safety glasses and sturdy footwear. Before buying or installing recycled floorboards check them for dry rot and woodworm. If left untreated, these can spread to other wood in your house, including structural timber.