If you require a fitting service, we can arrange for a wood flooring professional to give you a free quotation for the installation and finishing of your wood floor.
Solid wood flooring packs need one week to acclimatize to room humidity and temperature and should be left unopened horizontally on the intended floor. The room temperature at the time of installation should be at least +18°C. and the packages should only be opened once installation has commenced, not beforehand.
Sub floor Preparation
Like many projects, preparation is the key to trouble free success. Wood floor installation is no exception and the key to this is ensuring that the sub floor is in good condition.
Hot Tip: Make sure the sub floor is sound and level
The floor must be level and free from excessive moisture. Ground floors or lower basement and cellars should have a Damp Proof Membrane on the sub floor. Solid Hardwood floors must be laid on a dry, flat, solid sub floor and it is recommended that they are fastened directly to the sub floor with one of two methods:
The level of floor when measured with a 200cm ruler, should have a maximum allowed deviation of 3mm. If the deviation exceeds 3mm, then the floor must first be levelled using either a suitable self levelling compound board. An old wooden floor should be nailed down if necessary to make sure it is solid and washed first to avoid any unpleasant odour.
Most wood and laminate floors are not recommended for installation in a bathroom or shower room because of the risk of moisture penetration of the wood floor. However people do install wood floors in bathrooms without problems but this is at the customers own risk.
This risk is increased when using chipboard or MDF backed laminate flooring which will permanently swell when in contact with excessive water. However the risk is reduced when using engineered wood flooring with cross ply construction which reduces the likelihood of expansion and contraction.
The relative humidity of a concrete floor without a moisture barrier must be less than 60% and with a moisture barrier, less than 80%.
To check the humidity, either use a hygrometer, moisture meter or place a plastic sheet firmly over the floor for 4-5 days. If there are water droplets underneath the plastic sheet or if the concrete has turned a darker colour then the floor is too moist.
It is recommended that the sub floor is treated with a damp proof solution underneath the hardwood boards to prevent moisture causing excessive expansion and contraction in the floor boards.
Hot Tip: - If in doubt, then treat it!
All wood flooring products require an expansion gap usually 10 - 15mm for wood all the way around the perimeter of the room and including door frames, radiator pipes etc. The gap can be covered with skirting or cover moulding strip. In larger floors, the gap should be 1.5mm per each metre crosswise, for example in a floor 8m wide 8 x 1.5mm = 12mm.
If the floor covers a large, continuous area more than 8 metres wide, an expansion joint should be inserted into the hardwood floor. To make an expansion joint, do not apply glue on the board's long side, but make a so-called dry joint instead. Cut the boards crosswise and cover the seam with a strip, if necessary. The expansion joint should be placed under a threshold, into a corner or other suitable place.
For aesthetic reasons it is best to lay the floor boards in the direction of incoming light. However if the floorboards are being installed on an existing wooden floor, it is recommended to lay them crosswise at ninety degrees.
General Installation Instructions
Always start from a solid wall and check that the wall is straight. If the wall is not straight, draw a line matching the shape of the wall on the first boards, and cut them to fit the shape of the wall.
Use plenty of wedges to ensure that the expansion gap remains constant.
Start from a solid wall with the groove of the first row of boards facing the wall.
Use a plumb line to make sure that the row is perfectly straight because if it is not straight it will create problems when installing across the entire floor.
Hot Tip: Spend time getting the first boards absolutely straight and square
Always cut the last board in the row so that the cut edge finishes at the wall, leaving the required expansion gap.
Start the next row at the opposite end with the cut piece left over from the previous board so long as it is of sufficient length.
Stagger the end joints in each floorboard so that the end joints are spread out in a brickwork pattern for maximum strength.
Use a block to close the tongue-and-groove joints together or hire a secret nailing tool to push the boards together and nail them. Ensure that all the tongue and groove joints, including the end joints are fitted together tightly with no gaps
Nail the boards with secret nailing technique into the tongue of the board at a forty five degree angle or glue the wood to the sub floor with specialised wood flooring glue such as the Sika range of wood flooring adhesives.
Use straps and pull bars to pull the boards together and to hold them.
Fitting the Last Board
Place the last floorboard exactly on top of the previous
Use an off cut and place the tongue side to the wall, but with an expansion gap wedge.
Draw a line on the last board underneath following the edge all the way along.
Saw the board along this line and ease the board into place using a small crowbar or lever.
Remember to use the expansion gap wedges.
First cut the board to required length.
Place it on top of the last board to be fitted.
Using a T square, mark the pipe diameter on the board with two lines.
Measure the distance of the pipe from the fitted board and mark it.
Drill holes for the pipes ensuring that it allows for the expansion gap around the pipe.
Saw off the piece that will be placed behind the pipes
Glue on all sides of the loose piece and place it behind the pipes
Shorten architraves and door frames so that wood floor can fir underneath.
Use an off cut of floorboard and an allowance for any levelling material to cut the correct amount away for the floorboard to fit underneath.
Specialist tools can be hired to make this job easier
Remove all wedges from the expansion gap.
Hold the skirting down to the floor and nail it.
Beware of holding it too tight against the floor which could prevent its normal expansion and contraction.
Installation with Underfloor Heating:
Underfloor heating beneath wood flooring presents special problems because of the wide range of temperature to which the flooring is subjected. During the summer or when the heat is turned off for long periods, high atmospheric humidity causes an increase in the moisture content of wood flooring which has been specially dried for heated conditions. This produces lifting or distortion if the floor has been too tightly jointed at the time of laying. When the heat is turned on again, the moisture content decreases, therefore a greater seasonal moisture content variation is to be expected with underfloor heating than with other forms of heating.
Follow the guidelines detailed in this section in conjunction with the installation guides for engineered floors.
•Avoid accelerated drying of new concrete/screeds over UFH as this may lead to poor cohesive strength of the sub-floor.
•Check the cohesive strength of screeds before adhering.
•Ensure that screeds, concrete, etc are < 65% RH before installation commences.
•Employ a suitable surface applied moisture barrier (e.g. moisture suppressant primer) where necessary.
•If levelling is required above a suitable primer moisture barrier, apply a purpose-made fine graded aggregate over the second coat (on one coat membranes) OR third coat (on two coat membranes) immediately after application. Allow to cure then vacuum off all loose aggregate; (This will aid adhesion between primer and levelling compound). Then use a rapid dry formulae‚ water-mix (i.e. instead of latex mix) levelling compound, as these are typically stronger and develop strength quicker.
•Ensure that levelling compounds are fully cured and dry before installation commences (see manufacturers technical data-sheets).
•Use a purpose made, permanently flexible adhesive such as 1-part polyurethane, or Silicon Modified Polymer, when adhesive fixing.
•Fully-bond, rather than use, liquid battens‚ type adhesive systems with UFH.
•Ensure full contact between the underside of the flooring element and adhesive.
•Maintain suitable ambient humidity 45 to 65% RH. (Monitor with a domestic hygrometer).
•Employ floor temperature sensors below the floor with electric under floor heating systems.
•Do not Use solid flooring, Vanilla Wood Floors do not recommend solid wood floorings for UFH applications or high movement hardwood species such as Beech and Maple.
•Do not allow humidity below 45% RH, or above 65% RH. (A small domestic humidification unit can be employed to avoid low humidity during the winter heating cycle if necessary.
•Do not allow the floor temperature to exceed 27°C, (including under rugs).
•Do not use thick insulating rugs. (Note: as this will lead to high floor temperatures).
Selection of species for use with underfloor heating
Selection of species for use in floors subject to underfloor heating should be limited to those with particularly small thermal and moisture movement or should be as recommended by manufacturers who have extensive experience in the supply of flooring to be used over underfloor heating. Construction which permits an air space directly under the floor should be avoided as this can cause undesirable temperature fluctuations but advice on this should be taken from the manufacturers of the underfloor heating.
Precautions prior to installation where underfloor heating is to be used
Before floor laying begins, the following procedure should be followed:
The screed should be dried in accordance with BS8201:2011. Once the screed is dry to a maximum level of <75% RH, or <65% RH for floors directly bonded to the screed, the underfloor heating should be commissioned in accordance with the underfloor heating manufacturers guidelines where available.
Where no guidelines are indicated the following protocol should be followed:
a) Heating up. The flow temperature should be heated to a specific temperature as follows:
1) Day 1: 20°C
2) Day 2: 30°C
3) Day 3: 40°C
4) Day 4: 50°C or the maximum planned operating temperature. This should be maintained constantly for a minimum of 7 days.
b) Cooling Down. The flow temperature should be cooled to a specific temperature as follows:
1) Day 12: 40°C
2) Day 13: 30°C
3) Day 14: 20°C
4) Day 15: The underfoor heating should be switched off.
At least 4 days should elapse before final moisture readings are recorded (If more than 7 days elapse between the last cooling-down day (day 14) and the start of laying, the underfloor heating should be run at a minimum operating temperature of 40°C for 2 days. The underfloor heating should then be switched off for at least 4 days before a further moisture check is carried out prior to laying.
With some adhesives it is necessary to allow the screed to cool before laying the floor but the ambient humidity and temperature conditions within the area should always be maintained, and it might be necessary to have the moisture content of the screed at a lower level than 65% RH. The adhesive
Manufacturer’s recommendations should be followed.
Testing of UFH services
The flooring installer should ensure that all services (not only heating services) running beneath the floor have been tested fully by the services installer before laying starts.
Provision for expansion
•As a guide only allow a minimum 12mm expansion wherever the floor meets obstacles including perimeters walls, structural supports, hearths etc.
•Create additional expansion breaks in doorways using suitable profiles such as T-section thresholds or other transition strips.
•Create additional expansion breaks in large floors.
•Where practical install flooring parallel to the longest walls so that the direction of greatest potential expansion (i.e. across the grain) does not coincide with the direction of greatest dimension, esp. in large floors.
•The precise combined provision for expansion must be judged by the installer taking into account environmental humidity, moisture content of wood at time of installation, timber species and size of the floor.
Precautions prior to handover
Means of keeping the flooring dry and stable in the period between laying and handing over should be provided.
Start up schedule
Where underfloor heating is involved, particular attention should be paid to ensure that the top surface temperature of the wood flooring should not exceed 27 °C. Some electrical underfloor heating systems are not compatible with timber flooring and the manufacturer of the timber flooring should always be consulted before installing over underfloor heating systems, particularly regarding the moisture content, species of the timber and specific installation guidelines. It is most important that electrical UFH systems must be overlaid with a fibre reinforced smoothing compound of not less than 5mm no direct contact of any electrical matting should come into contact with the wood floor itself. Please seek the advice of the UFH manufacturer’s instructions to confirm compatibility with wood flooring.
Always check the mutual compatibility of moisture barriers, primers, aggregates, levelling compounds and adhesives before installation.
Disclaimer & further information
This information is not intended to be exhaustive, or a how to guide for the novice, but will serve as a guide only to the experienced installer. Further information is available in request.