A solid oak floor is one of the finest floor finishes on the market. It is instantly useable, hardwearing, beautiful to look at and most of all it improves with age. It is a top of the range product that doesn’t come cheap but if you lay it yourself you will save as much as half the supply and fit cost. This guide will hopefully fill in any gaps in your knowledge and give you the confidence to have a go. When it comes to cutting the boards it is a question of good tools and accurate measuring. This can only be gained by experience but some careful thought with the first few boards will set you up perfectly to cover the rest of the room.

What is an oak floor?

The very best solid oak floors are cut in a timber mill from kiln dries timber. It is important to distinguish solid oak from engineered boards or laminate. Engineered boards are advertised as solid wood because they are a thin layer of oak (about 5mm) glued to plywood. This gives a very stable board but it does not have the inherent natural beauty of a true solid board.

Sizes

Standard depth of oak boards is just under an inch, varying between 20-22mm. As the boards are cut from whole trees they are restricted by the original size of the trunk. Standard boards are about 8 inches wide. The most important measure is the ‘cover’ of the board. This is how much of the board is seen after it is fixed so it doesn’t include tongues. An 8” board produces a cover of just over 180mm. Wider or narrower boards are available as required. Wider boards come with a greater chance of cupping

If ordered from a timber mill the boards will be supplied in random lengths, varying from approx. 500mm to 3000mm.

Acclimatising the oak

Most important for ensuring a good oak floor is to allow the oak to adjust to the humidity of its new home. This is easy to do, but is frequently ignored. Stack the oak with spacers between the boards to allow it to breath and leave the oak in the room in which it will be laid for at least a couple of weeks. Failure to do so could lead to warping as the floor swells or shrinks once it has been laid.

Sub-floor

The type of base upon which the oak will be laid dictates the method used to secure the boards.

Concrete/Screed.

There are a number ways to lay oak onto a solid sub-floor. It is crucial if laying on a new floor that the concrete or screed is allowed to dry. Screeds dry at a rate of 1mm a day so allow the sub floor plenty of time to dry.

• Timber battens. Approx. 50x50mm softwood secured to the concrete and each other spaced 400mm apart with noggins can be laid down. The oak planks can then be fixed to the battens. Insulation can be laid between the battens if desired.

• Floating floor. This method also allows the opportunity for insulating beneath the floor. A layer of Jablite or Celotex type insulation is laid on the floor and then covered with flooring chipboard, available in 2400x 600mm. The boards are glued together but the floor is not fixed down. Then the oak is fixed to the chipboard.

• Elastilon A self adhesive roll that grips the boards. It requires no other fixings. Visit www.elastilon.com for more information.

• Wood floor adhesive. Supplied in ready mixed tubs, this PU adhesive is spread on the floor and bonds the wood to the sub-floor.

Timber floor

On a pre-existing timber floor, in sound condition, the oak can be fixed to the floor joists or even onto the floor boards. Take care to avoid nailing through pipes or cables concealed within the floor void.

Laying the floor

• The first task is to decide which way the boards should run in the room. If they run along the length of the room it will appear longer, across the room and it will appear wider. Boards must run at right angles to the floor joists so in some cases the decision will be made for you.

• The floor will come with tongue and groove edges and square cut ends. A top tip is to soften the edges of the boards with sandpaper so the joints between the boards become more conspicuous. This will better disguise any deviations in the joints.

• To join boards end to end use a biscuit jointer. This will stop the ends lifting or warping and is essential if the ends of the boards are not supplied tongue and grooved, as most solid floors are not.

• It is important to stagger joints in boards. No end joints should be within 300mm of a neighbouring joint, and never have a regular pattern of joints. When laying on joists this is particularly important as it is easy to end up with a regular pattern of joints across the room. Selecting boards from your stock at random is the best and quickest way to ensure the floor has a natural appearance.

Secret nailing

Where boards are being fixed to timber, nails will be needed to hold the floor down. For a traditional look use flooring brad nails fixed through the top of the boards, a pair in each joist. But a far more modern look can be achieved by secret nailing the boards. A nail is driven through the tongue of the board at an angle. Pilot drill the hole for the nail first, and then drive the nail home and finish it flush with a nail punch. The next board will fit over the tongue and thus conceal the fixing. As shown in the two pictures above.