Engineered oak flooring guidelines

We always recommend that you employ a proven professional for the installation of oak flooring, but here are some important guidelines to consider to ensure a smooth installation process.

When Your Oak is Delivered

We recommend that our engineered oak flooring is delivered 3-5 days prior to installation so that the timber can be acclimatised.

You should carefully check your order at time of delivery and report any issues or concerns. If the planks are delivered plastic wrapped in packs, then the packs should be carefully slit open along the length on one side of the pack, making sure that the pack remains intact so that the planks are prevented from sliding around when moved.

It is very important that the site conditions are right at the time of delivery and storage:

  • Buildings should be wind and water-tight, and external windows and external doors fully installed and finished.
  • All wet-works (e.g. plastering and painting) should be complete.
  • The fabric of the building dried out with no visible signs of moisture or condensation.
  • The heating should be on and ambient air conditions should be within the temperature range of 15 to 27 degrees centigrade and 35% to 65% (BS8201) relative humidity.
  • Never acclimatise timber products over a floor screed that has not been proven to be sufficiently dry – this is especially important where the floor screed contains an underfloor heating system.
  • All timber products should be stored flat and raised off the floor on battens.
  • Timber flooring of any kind should never be stored outdoors, placed directly onto a screeded floor, in a garage or in any damp conditions.

Prior to Installation

The method of installation used is very much dependent on the subfloor type, whether there is underfloor heating and the size of the areas to be fitted. It is the responsibility of the installer to ensure that the site conditions are right before deciding on which installation method to use.

Subfloors – are they suitable for oak flooring?

It is important that subfloors are checked and prepared correctly, as problems with the subfloor can result in squeaky boards, bouncing floors, shrinkage, cupping floorboards, de-bonding floors or even the de-lamination of the oak top layer from the birch plywood backing. Our installation team recognise that a finished floor will only be as good as the subfloor that it is laid on and that’s why we will do what it takes to ensure that you have the best prepared subfloor possible, prior to beginning installation. There are no shortcuts!

New subfloors should be prepared in line with British Standards 8201 and 8204, with no more than a 3mm deviation over a 2m run in any direction.

Joists

  • Joists should be spaced at a maximum of 400mm centres and squeaky and uneven joists should be rectified.
  • Any signs of dampness should be addressed.
  • Any joist with signs of insect attack such as woodworm should be treated.
  • If worried about draughts coming up through the floor, then an underlay or hardboard can be fixed to the joists first.

Existing Floorboards, Chipboard or Hardwood

  • Any squeaking or bounce should be eliminated.
  • Subfloors should be level and even – any unevenness in the subfloor will be apparent in the oak floor covering.
  • Existing floorboards often need some repairs and levelling to provide a suitable subfloor. The existence and depth of pipes under the floorboards should be carefully checked out too.
  • New boards should run perpendicular to existing floor boards or overlay with ply first.
  • If fixing plywood this should be screwed at 6” centres.
  • If floating the flooring, then acoustic underlay can be laid between the subfloor and oak flooring to reduce the sound of footfalls, which is particularly beneficial in upstairs rooms.

Screeds – Concrete, Cementitious or Anhydrite

  • Screeds should be smooth, level and even (no more than 3mm deviation over a 2m run in any direction).
  • If existing or new concrete or screed subfloors are not even or smooth, then a levelling compound should be used to provide a suitably level and smooth surface.
  • The surface of the screed should be non-friable and laitance free prior to the application of any priming or adhesive products.
  • New screeds must be cured and dry prior to the installation of oak flooring. The moisture content of the screed is a critical factor that must be considered prior to wood floor installation.
  • In general, the curing rate of a screed is 1mm per day for the first 40mm of depth, thereafter the rate is 0.5mm per day; therefore a 70mm screed will take 100 days to cure. Please note that curing is different to drying. Screeds with underfloor heating will not dry to the required moisture content until laitance has been removed and heating switched on. Because of the different types of screeds available, specific advice on curing/drying time should be sought from your screed supplier or installer.
  • Screeds can be checked for moisture using moisture meters such as Protimeter or Tramex hand-held meters, or a Hygrometer box can be installed (this is the recommended method as per code of practice BS 8201).
  • Screeds should have a relative humidity of less than 75% before installation commences, or a moisture content reading of 2% or less on the concrete scale of a Tramex meter. There should be no evidence of moisture or dark damp areas under weighed down plastic sheeting or similar.
  • If the screed does not have underfloor heating, then it may not be possible to achieve a relative humidity level in the screed of less than 75%, or a moisture content reading of 2% or less on the concrete scale of a Tramex meter. In this case it may be possible to apply a liquid damp proof membrane prior to bonding*. If the screed also requires levelling, then the damp proof membrane should be applied first, and then when dry the levelling compound applied.

*In no circumstances should a damp proof membrane be applied over the surface of an anhydrite screed, as this will trap moisture in the screed and cause it to disintegrate.

Under Floor Heating

  • Consideration should be given to the design of any underfloor heating systems, as extreme heat exposure in specific areas may cause timber shrinkage and damage to the planks – for example, thought must be put into those areas where UFH pipes converge such as at the underfloor heating manifold or in narrow corridors.
  • We recommend that floor thermostats are specified as a supplement to the standard air thermostat and that this is set as the master control – surface temperature should never exceed 27 degrees centigrade.
  • If an underfloor heating system has been installed with no floor thermostats then measures may have to be taken with the floor design to prevent floor shrinkage.
  • In the case of screeded subfloors, underfloor heating systems must be commissioned and running to ensure that any hidden moisture is driven out of the subfloor. Commissioning should include slowly turning up the heating until it runs at normal operating temperatures for an extended period of time. Advice should be sought from your screed and underfloor heating supplier.
  • Appropriate expansion gaps, movement joints and room breaks should be designed into the floor structure.
  • At the time of installation, if the floorboards are being glued down then, depending on the room temperature, the underfloor heating system may have to be turned up, switched off or turned down – refer to the floor adhesive manufacturer’s guidelines for instruction regarding application temperature requirements.

General Points

  • Care should be taken to ensure that a balanced look is achieved when laying out the floor. There will be shade and character variation in the planks so several packs should be worked from at a time.
  • The planks come in random lengths so the short and long lengths should be distributed equally over the whole floor area.
  • Flooring is best installed at right angles to the floor joists or to the direction of existing floorboards and, if possible, the plank direction should be parallel to the longest dimension of the room.
  • The end joints of the flooring should be staggered to achieve the best appearance and to avoid clustering of end joints.
  • It is important to establish the optimal starting point, from which to align your first row of planks. Rooms or areas can have walls or features that are not perfectly square, which can cause the boards to run (or taper) out. Careful thought and design will help disguise such effects.

INSTALLATION

Secret Nailing

Our 20mm thick wood flooring can be secret-nailed onto joists or timber subfloors using herringbone serrated flooring nails and a powernailer. Acoustic/insulation/DPM underlays can be included as required. We do not recommend nailing our 16mm thick boards – these should be floated or glued down. We also do not recommend nailing to chipboard because nails can work loose over time and may cause squeaking.

Floating

If it is not possible to nail down the floor boards, for instance because the subfloor is concrete, then the boards can be installed using the ‘floating’ floor method. This is, however, not recommended for areas spanning more than 4m across the width of the room or for room areas larger than 40m2. We recommend that an acoustic underlay is used to help deaden the sound of footfall – this can incorporate a damp proof membrane too. The boards are first glued together using a suitable PVA adhesive in the tongue & groove on all four sides, and then ratcheted to pull the boards tight so that they adhere under tension.

Direct Bonding to Subfloor

This is our recommended system for installation over screeds and in-screed underfloor heating. The floorboards are bonded directly to the concrete or screeded subfloor, by priming first and then gluing down using a professional polymer adhesive system. See note above regarding moisture content of the screed.

Ongoing Maintenance

See our Maintain you Floor page, for all information regarding maintaining your oak floor.

When Your Oak is Delivered

We recommend that our engineered oak flooring is delivered 3-5 days prior to installation so that the timber can be acclimatised.

You should carefully check your order at time of delivery and report any issues or concerns. If the planks are delivered plastic wrapped in packs, then the packs should be carefully slit open along the length on one side of the pack, making sure that the pack remains intact so that the planks are prevented from sliding around when moved.

It is very important that the site conditions are right at the time of delivery and storage:

  • Buildings should be wind and water-tight, and external windows and external doors fully installed and finished.
  • All wet-works (e.g. plastering and painting) should be complete.
  • The fabric of the building dried out with no visible signs of moisture or condensation.
  • The heating should be on and ambient air conditions should be within the temperature range of 15 to 27 degrees centigrade and 35% to 65% (BS8201) relative humidity.
  • Never acclimatise timber products over a floor screed that has not been proven to be sufficiently dry – this is especially important where the floor screed contains an underfloor heating system.
  • All timber products should be stored flat and raised off the floor on battens.
  • Timber flooring of any kind should never be stored outdoors, placed directly onto a screeded floor, in a garage or in any damp conditions.

Prior to Installation

The method of installation used is very much dependent on the subfloor type, whether there is underfloor heating and the size of the areas to be fitted. It is the responsibility of the installer to ensure that the site conditions are right before deciding on which installation method to use.

It is important that subfloors are checked and prepared correctly, as problems with the subfloor can result in squeaky boards, bouncing floors, shrinkage, cupping floorboards, de-bonding floors or even the de-lamination of the oak top layer from the birch plywood backing. Our installation team recognise that a finished floor will only be as good as the subfloor that it is laid on and that’s why we will do what it takes to ensure that you have the best prepared subfloor possible, prior to beginning installation. There are no shortcuts!

New subfloors should be prepared in line with British Standards 8201 and 8204, with no more than a 3mm deviation over a 2m run in any direction.

  • Joists should be spaced at a maximum of 400mm centres and squeaky and uneven joists should be rectified.
  • Any signs of dampness should be addressed.
  • Any joist with signs of insect attack such as woodworm should be treated.
  • If worried about draughts coming up through the floor, then an underlay or hardboard can be fixed to the joists first.
  • Any squeaking or bounce should be eliminated.
  • Subfloors should be level and even – any unevenness in the subfloor will be apparent in the oak floor covering.
  • Existing floorboards often need some repairs and levelling to provide a suitable subfloor. The existence and depth of pipes under the floorboards should be carefully checked out too.
  • New boards should run perpendicular to existing floor boards or overlay with ply first.
  • If fixing plywood this should be screwed at 6” centres.
  • If floating the flooring, then acoustic underlay can be laid between the subfloor and oak flooring to reduce the sound of footfalls, which is particularly beneficial in upstairs rooms.
  • Screeds should be smooth, level and even (no more than 3mm deviation over a 2m run in any direction).
  • If existing or new concrete or screed subfloors are not even or smooth, then a levelling compound should be used to provide a suitably level and smooth surface.
  • The surface of the screed should be non-friable and laitance free prior to the application of any priming or adhesive products.
  • New screeds must be cured and dry prior to the installation of oak flooring. The moisture content of the screed is a critical factor that must be considered prior to wood floor installation.
  • In general, the curing rate of a screed is 1mm per day for the first 40mm of depth, thereafter the rate is 0.5mm per day; therefore a 70mm screed will take 100 days to cure. Please note that curing is different to drying. Screeds with underfloor heating will not dry to the required moisture content until laitance has been removed and heating switched on. Because of the different types of screeds available, specific advice on curing/drying time should be sought from your screed supplier or installer.
  • Screeds can be checked for moisture using moisture meters such as Protimeter or Tramex hand-held meters, or a Hygrometer box can be installed (this is the recommended method as per code of practice BS 8201).
  • Screeds should have a relative humidity of less than 75% before installation commences, or a moisture content reading of 2% or less on the concrete scale of a Tramex meter. There should be no evidence of moisture or dark damp areas under weighed down plastic sheeting or similar.
  • If the screed does not have underfloor heating, then it may not be possible to achieve a relative humidity level in the screed of less than 75%, or a moisture content reading of 2% or less on the concrete scale of a Tramex meter. In this case it may be possible to apply a liquid damp proof membrane prior to bonding*. If the screed also requires levelling, then the damp proof membrane should be applied first, and then when dry the levelling compound applied.

*In no circumstances should a damp proof membrane be applied over the surface of an anhydrite screed, as this will trap moisture in the screed and cause it to disintegrate.

  • Consideration should be given to the design of any underfloor heating systems, as extreme heat exposure in specific areas may cause timber shrinkage and damage to the planks – for example, thought must be put into those areas where UFH pipes converge such as at the underfloor heating manifold or in narrow corridors.
  • We recommend that floor thermostats are specified as a supplement to the standard air thermostat and that this is set as the master control – surface temperature should never exceed 27 degrees centigrade.
  • If an underfloor heating system has been installed with no floor thermostats then measures may have to be taken with the floor design to prevent floor shrinkage.
  • In the case of screeded subfloors, underfloor heating systems must be commissioned and running to ensure that any hidden moisture is driven out of the subfloor. Commissioning should include slowly turning up the heating until it runs at normal operating temperatures for an extended period of time. Advice should be sought from your screed and underfloor heating supplier.
  • Appropriate expansion gaps, movement joints and room breaks should be designed into the floor structure.
  • At the time of installation, if the floorboards are being glued down then, depending on the room temperature, the underfloor heating system may have to be turned up, switched off or turned down – refer to the floor adhesive manufacturer’s guidelines for instruction regarding application temperature requirements.
  • Care should be taken to ensure that a balanced look is achieved when laying out the floor. There will be shade and character variation in the planks so several packs should be worked from at a time.
  • The planks come in random lengths so the short and long lengths should be distributed equally over the whole floor area.
  • Flooring is best installed at right angles to the floor joists or to the direction of existing floorboards and, if possible, the plank direction should be parallel to the longest dimension of the room.
  • The end joints of the flooring should be staggered to achieve the best appearance and to avoid clustering of end joints.
  • It is important to establish the optimal starting point, from which to align your first row of planks. Rooms or areas can have walls or features that are not perfectly square, which can cause the boards to run (or taper) out. Careful thought and design will help disguise such effects.

INSTALLATION

Secret Nailing

Our 20mm thick wood flooring can be secret-nailed onto joists or timber subfloors using herringbone serrated flooring nails and a powernailer. Acoustic/insulation/DPM underlays can be included as required. We do not recommend nailing our 16mm thick boards – these should be floated or glued down. We also do not recommend nailing to chipboard because nails can work loose over time and may cause squeaking.

Floating

If it is not possible to nail down the floor boards, for instance because the subfloor is concrete, then the boards can be installed using the ‘floating’ floor method. This is, however, not recommended for areas spanning more than 4m across the width of the room or for room areas larger than 40m2. We recommend that an acoustic underlay is used to help deaden the sound of footfall – this can incorporate a damp proof membrane too. The boards are first glued together using a suitable PVA adhesive in the tongue & groove on all four sides, and then ratcheted to pull the boards tight so that they adhere under tension.

Direct Bonding to Subfloor

This is our recommended system for installation over screeds and in-screed underfloor heating. The floorboards are bonded directly to the concrete or screeded subfloor, by priming first and then gluing down using a professional polymer adhesive system. See note above regarding moisture content of the screed.

Ongoing Maintenance

See our Maintain you Floor page, for all information regarding maintaining your oak floor.

These are very general guidelines and not definitive instructions. The issuer of these guidelines cannot be held responsible for any issues related to installation