How To Guide Solid Strip & Overlay Floors Installation Guidelines Sub-Floors Sub-floors should be dry and level, no more than + or - 3mm over 3.0 mtr in any direction. Moisture content of the concrete should be no more than 5%. New concrete normally takes around 1 month per 25mm to dry or 1mm per day.
Site Conditions All building work including wet trades should be finished; there should be no visible or measured signs of moisture or condensation. The building should be heated (including normal ventilation) to its operating temperature for at least 1 month prior to the floor being fitted.
On Delivery All solid Hardwood/Softwood flooring should be left to acclimatise (sit) in the room for around 14 days prior to the installation. The temperature should be around 15 - 25 degrees C, and the relative humidity should be between 40 - 50%.
Installation 20mm strip floors can be nailed onto battens or joists, existing timber floors or a plywood or chipboard subfloor. Joist or batten centres should be around 300mm spacing, flooring can be secret nailed through the tongue onto the sub-floor. A 12mm expansion gap should be left around the perimeter of the floor; either a skirting or beading to finish the floor can cover this. Occasionally you may need to leave an expansion gap across the width of the floor at regular intervals depending on how wide the expanse is. Solid overlay floors should be PVA glued on the back of the boards and then pinned through the tongue every 300mm onto an existing timber floor (always running in the opposite direction) or onto plywood or chipboard sub-floors.
Sanding and Sealing The first sanding is normally done with a large floor sander using progressively finer grits for a smooth finish; the floor can then be finished with either a lacquer or oil, depending on your choice. With the lacquer 1 coat of primer is normally applied first and then 2 coats of the actual lacquer.
Trouble Shooting Flooring should never be left outside in the elements, it is Hydroscopic and will absorb moisture and therefore shrinks when fitted. Before laying, it is important to recognise any services, especially electrical, water and heating systems. If a nail during fitting goes through a water pipe it will leak and be absorbed by the floor and expand causing rafting. Page 34