RECLAIMED WOOD FLOORING – INSTALLATION GUIDELINES
A reclaimed wood floor is an asset for any property. Installed correctly and finished sympathetically, it will enhance the appearance and provide a durable and functional feature to last as long as the property stands. Any short cuts made throughout the installation process – from purchase of the floor to the final coat of finish – will affect the finished article in both longevity and durability, as well as lessening the intrinsic beauty that reclaimed wood floors provide. Traditional and antique wood floors have always been installed in a thorough and methodical fashion and as such they remain serviceable for centuries. Modern construction techniques and lack of skilled tradesmen, coupled with an insatiable thirst for ease of use and speed of completion, have directly threatened the correct procedures required to achieve faultless reclaimed solid wood installation.
Sub-floors and climatic conditions for Reclaimed Wood Flooring
Moisture content and acclimatisation of timber
To service a centrally heated environment, reclaimed and new solid wood floors will need to contain a moisture content of between 8% and 12% (an average of 10%), no more, no less. Timber should be acclimatised in a sealed, dry and, if necessary, heated site prior to installation. Timber should either be laid out or placed with sticks in between (to aid circulation of air) away from any direct sunlight or windows for this introductory period prior to installation. This should be for no less than 7 days.
Sub-floors - Suspended
Reclaimed timber flooring will need to be installed to a securely fastened, level and dry subfloor without contamination. The moisture content of the sub-floor will need to be in equilibrium with the timber flooring it is going to receive. Plywood sub-flooring or joists will need to be checked for both structural integrity and moisture content prior to the arrival of timber flooring. Plywood will need to be a minimum of 18 mm in thickness and of WBP grade. Chipboard is not suitable for mechanical fixings and should only be provided for floors that are to be fixed to the sub-floor with a flexible wood flooring adhesive.
Sub-floors - Solid
All concrete sub-floors will need to be fully dried and sealed with a minimum of 2 coats of a compatible liquid Damp Proof Membrane (DPM). A solid concrete floor is dry from the moment it reads 65% or less relative humidity across its entire area. If a self-levelling latex top coat is required to smooth the surface then this will need 1 day per millimetre of drying time prior to application of a liquid DPM. Adhesives used for the flooring will need to be compatible with the liquid DPM.
Installation of solid wood flooring - Mechanical fixing
Nail-down installation is the most straightforward installation method but is only advisable if you have a wooden sub-floor. This installation method is typically performed by a professional as it requires certain skills and a level of knowledge on the process as well as the use of specialist tools.
When installing over Plywood or composite board, the direction chosen to lay the planks does not matter; however, if the new flooring is nailed down over existing floorboards, the new planks must be installed at a 90° angle to the originals. This is done to ensure stability and to avoid the risk of excessive movement, buckling or warping.
Installation of the solid wood flooring should start at one end of the room and then a ½ inch gap should be left around the entire perimeter to allow for expansion.
For tongue and groove floors, fitters should nail a soft wood batten in place as the centre line and carefully select several of the straightest boards. They should then place the boards against the batten and nail through the tongue, predrilling and nailing at a 45° angle with a manual or pneumatic floor-nailer.
The floor nail or cleat used should be ring-shanked or jagged and no less than 2.5 times the thickness of the boards. They should be set into each floor joist or batten 16 inches apart. Boards must have a minimum of two nails each. No two connecting boards should end on the same line so the installer should alter lengths, staggering the joints at least 6 inches apart. Often the last row will not fit a full strip of flooring and should be cut so the installer is able to hand nail the last row, leaving enough space for a ½ inch expansion gap between the wall and the wood.
Installation of solid wood flooring – Adhere to sub-floor
Glue-down installation requires the use of an adhesive or bonding agent applied directly onto the sub-floor, and can be used with both concrete and wooden sub-floors. Some of these adhesives are designed with under floor heating in mind and can be used for both solid and engineered floors. Laying over a concrete sub-floor will first require a two-part epoxy liquid DPM to ensure no damp rises into the new floor.
The glue-down installation method can provide an extremely stable floor when done properly, although it will require a slightly longer overall installation period. As with other installation methods, the installers should leave an expansion gap around the perimeter and follow the same laying pattern. This method can be used for wide planks although it is more commonly used with parquet flooring.
Floating floor installations
The floating method of installation will require pre-laying an underlay in order to provide a cushion between the floor and the sub-floor. On ground and basement levels or above concrete sub-floors the underlay should combine a built in DPM. An acoustic option underlay should be used in multi occupant buildings to provide sound reduction between floors. The floating method will only lend itself to engineered boards; although these must be narrow boards, wide engineered planks are not recommended to be used for this method.
Once the underlay has been fitted, the installers should start laying the planks from one end of the room and leave a ½ inch gap around the entire perimeter to allow for expansion. Nails are not used; the boards either connect using a click system or the tongue and grooves are glued together. The only downside to floating floors is that they are more likely to “creak” and the PVA glue that is commonly used can break down over the years, meaning the joints weaken.
Sanding and finishing of Reclaimed Wood Flooring
Gone are the days of systematically sanding the life and soul out of wood floors. Their patina and character is evidence of a bygone era and is individual to each and every floor salvaged from its previous dwelling. The colour in the original surface is unique and is impossible to replicate to any degree of authenticity whether using pigments or hand distressing. The sanding and finishing should be assessed individually with each batch of reclaimed wood flooring. A sympathetic approach should be adopted with buffing, scraping or hand-held machine sanding with fine grit sandpapers to achieve the correct degree of restoration. Finishes should be selected based on the amount of footfall expected on the floor, regularity of maintenance and desired hue and sheen.
From a telephone consultation to a complete design and installation service, Thomas Mountford @ T M Flooring Supplies Ltd can offer a complete and comprehensive service complete with guarantee using LASSCO Floorings reclaimed wood flooring range.
T M Flooring Supplies Ltd
No 79 Clyde Road
London N15 4JZ
07946 496 365