The Benefits of Starting from the Centre Line

When our floors are being nail-fixed and the width of the floor is greater than 12m we recommend that the installation is started from the centre line and the boards laid out towards the opposite walls.
 
The drawing below shows how the first pair of boards are jointed together and fixed.
 
This means that two teams of installers can work separately from one another and so the installation time is reduced.

This also means that the floor will expand more evenly across its area and post socket covers will not go out of alignment.
 
When a floor is secret nailed the nails are driven in at a 45 degree angle. When the floor is set out from the centre line the nails in one half of the floor will slope in the opposite direction from the other half. This means that the natural expansion of the floor will happen evenly from the centre line of the floor towards the opposite walls. This makes the movement of the floor very predictable and ensures that best use is made of expansion gaps. Also if our Bushings are used this means that the Bushing is less likely to go out of alignment with the post socket below.
 
On the other hand, if a wide floor is set out from one side of the hall it will tend to expand more towards one wall than the other which can lead to the floor lifting... and a lot of head-scratching because this may be interpreted wrongly as a damp or humidity problem, but no signs of moisture will be found. Also bushings can quickly go out of alignment with the sockets.