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Installation Guide General Information for Wood Floors

You will find detailed and specific manufacturers’ installation instructions in our ‘Help Me’ section. It is important to carefully check and adhere to these instructions when installing your new floor.

Below you will find some general information and useful hints and tips for selecting and installing your new floor. These guidelines are not be used in lieu of the manufacturers’ instructions and only offer general advice.

Pre Delivery Conditions 

Before any materials are delivered to site all wet trades such as plastering, decorating and concreting / screeding should be complete and the working areas should be left to dry out. Areas should be watertight and hospitable.


All flooring should ideally be acclimatised where it is being installed; the packs of material should be left unopened and laid flat (preferably in the centre of the room away from walls), and the conditions should mirror those that will prevail following installation.

As a guide solid wood will take 7-10 days to acclimatise. Engineered / laminate products will require only 24-48 hours.

While acclimatising, the flooring should lie horizontally and flat at the ideal relative humidity level of between 45 -55%. The room should be dry, if the building is a new building with a concrete floor, wait until the floor is completely dry.  The flooring should be laid at a minimum room temperature of 15c and a maximum of 22c.


The greatest possible care is taken to produce your floor.  However, we advise you to check the boards for visible defects such as damage and deviations in shape or dimensions.  No complaints regarding these visible defects will be considered after the boards have been laid.  Make sure you have good lighting while laying the floor.

Sub-floor preparation

Sub-floors tend to be either concrete or cement screeds, existing floorboards or joists and batons. 

Keep in mind the acronym LCDLevel, Clean and Dry! Level, Clean and Dry are the holy trinity of subfloor preparation, irrespective of whether you’re fitting over existing floorboards, plyboard, or concrete.

Level: Obvious, but important! Your Subfloor should not deviate more than 3mm in depth over a 2m length.

Clean: Less Obvious, but still important. Dust, Dirt and Debris create an uneven surface which can play havoc with adhesives and affect your flooring once it’s laid.

Dry: Even less Obvious, and often esotericMoisture issues are the commonest cause of flooring failureYou’ll need to think about Moisture Content and Relative Humidity. Moisture Content measures the quantity of water in a material and is typically expressed as a percentage. Relative Humidity measures the amount of water vapour in air as a percentage of the amount needed for full saturation at a given temperature. The formulas for calculating these measurements are intimating, but handy gadgets, particularly from the likes of Tramex, can calculate these for you.  

Concrete or Cement Screeds

If you’re planning to put wood flooring in a ground-floor area, it’s more than likely that you’ll be fitting onto a concrete subfloor. 

Be very cautious about laying wood flooring on top of a recently laid screed! As the screed dries it releases will cause affect your wood floor. Screeds can take a surprisingly long time to dry. A good rule of thumb is to allow one day per millimetre of screed depth. You can use a Concrete Moisture Meter to take a moisture content reading. If your screed has a moisture content of more than 4% it’s not ready to fit your Wood Flooring over.

A drying screed can also affect the relative humidity in a room! Use a digital protometer or a surface mounted hygrometer to take your measurements. Wood Flooring is happiest in a relative humidity of between 45% and 55%. It’s a good idea to take a relative humidity reading even if you don’t have a drying screed to worry about!

If you have a moisture content or a relative humidity issue a damp proof system, or a sheet-type moisture or vapour barrier should be considered.    

If your screed isn’t level because of cracking or sinking you can use a self-levelling compound, process known in the trade as ‘latexing’ because the latex contributes to the flexibility of the compound. You should make sure the screed is clean and free of dust and debris and ‘primed’ before applying the compound. Once you applied enough layers of the compound to level the area it’ll take approximately 24 hours to dry.

Once the screed is level and dry you have two different fitting options: Floating and Gluing.

Existing Floorboards

If you’re fitting your wood floor over existing floorboards, remember that these must be fixed down, secure, level and in a good general condition. Again, if there is a deviation of 3mm in the level of the floor over a 2m length, we wouldn’t recommend fitting your floor directly over the floorboards.

You must lay your new boards perpendicularly (at a 90-degree angle) to the original floorboards to ensure they’re stable. If this conflicts with your interior plans, you’ll need to fit 6mm plyboard over the original floorboards which will provide a fresh surface to lay over.

Moisture in a wooden subfloor can also be a problem. A wooden subfloor should have a moisture content between 7 – 11% before Wood Flooring can safely be laid over it.

We’d still recommend having a look at the relative humidity in the room, even with a wooden subfloor. Again, it should measure between 45% and 55%.

If your laying directly onto existing floorboards, you’ll need to use the Gluing or Secret Nailing installation methods. 

If you have decided to ply over the boards to ensure a level surface you could fit using the FloatingGluing or Secret Nailing methods.  

Joists or Batons

If you’re looking for Wood Flooring in a new-build, a significant structural restoration or if your existing floorboards are no longer fit for purpose, you may need to lay your wood floor over the bare joists or batons.

This means that your Wood Flooring will need to be thick enough to be load bearing, known as a ‘structural’ board in the trade. Structural boards are usually between 18mm and 21mm in thickness and benefit from extra stability and durability (the veneer is usually larger on a structural board), although they tend to be more expensive.

If you’re set on a thinner board because there is a particular finish you like or because of cost implications, there is another solution. You can lay ‘structural’ 18mm ply over the joists, forming a level surface which you can lay thinner boards over. This solution tends to significantly raise the final floor level, which is something to bear in mind. 


Before flooring arrives on site or installation commences, the room temperature and atmospheric relative humidity must be stable. All heating systems should be commissioned and operating for 2-3 weeks in advance. Where an under floor heating system is being used we would always recommend the use of an engineered or laminate floor as opposed to a solid wood floor, as the multi-layered construction offers more stability. It is imperative however that compatibility is checked with the specific manufacturer.


All of our products are rigorously checked; however it is important that every board or item is checked for defects prior to installation – there is nothing more frustrating than installing your floor to find an imperfect board in the middle; often with a little care and thought transit-damaged or imperfect boards can often be utilised in edge or perimeter cuts to avoid delaying the installation works.

Laying Direction

The normal laying direction for wood and other plank-type floor systems would be along the length of the room and if possible towards the direction of light. 

Selecting the correct floor 

Before preparing the base or installing your new flooring, you can make life easier by selecting the correct product: 


  • Laminate Floors

Laminate floors simulate the appearance of real wood. Its surface appearance is determined by a decorative foil that is coated with a tough transparent wearing layer for durability. The core is normally constructed from a HDF type product.

Generally these products can be laid as a floating floor system using an approved underlay and vapour barrier over most bases, providing that they are sound, smooth, solid, even, and free from moisture. These products feature jointing systems and are easy to use and install. Laminate floors will not be load bearing.


  • Engineered Floors 

Engineered floors are our most popular selling range of products, constructed from multiple layers of wood and compressed together with a real wood top layer, varying in thickness from approximately 3mm-6mm, with an overall board thickness of 14-22mm.

Engineered floors are available in a wide variety of species, and are a very stable and durable floor, typically with a clic-lock, glueless joint system.

Generally these products can be laid as a floating floor system using an approved underlay and vapour barrier over most bases (providing that they are sound, smooth, solid, even and free from moisture). Some thicker engineered boards (18-22mm thick) can be installed in a similar fashion to solid boards by either secret nailing or by approved stick down methods. These floors are suitable for all areas of the home but not normally in bathroom-type areas.

Engineered floors less than 18mm thick will not be load bearing. Floating systems also give the opportunity to select an underlay to suit your requirements. 

Most engineered systems can be installed over under floor heating (always check this with the manufacturer). These products feature jointing systems and are easy to use and install. 


  • Solid Wood Floors

Solid wood flooring offers a traditional choice. It looks beautiful and will last for generations, with a great feel underfoot. This product is typically available with a traditional tongue and groove-type joint.

Solid wood floors are usually installed using the following methods: secret nailing, fully adhered, liquid batten-type adhesive or self-adhesive underlay systems. 

Generally the nailing methods are used over wooden bases and the adhesive / underlay systems are used over concrete-type bases.

Products should be fully acclimatised prior to installation. 

Bases should be sound, smooth, solid, even and free from moisture.

Our solid wood floors are not suitable for use in bathroom areas or for use over under floor heating.

We would normally recommend that the installation of a solid wood floor is completed by an experienced tradesman.


  • Luxury Tiles 

Luxury Tile products are installed using the full stick down method with an approved adhesive. They can be installed in almost any area and are extremely durable. 

Subfloor preparation is the key to a perfect finish and all bases should be sound, smooth, solid, even and free from moisture. Sub-floor preparation of a good standard is imperative, and we would recommend that installation is completed by an experienced tradesman.

Installation Techniques

Floating Floors

Floating a floor essentially means that the new boards are loose-laid over a suitable underlay instead of being screwed, nailed and/or stuck to the subfloor. A floating floor can be installed over various bases including concrete, existing wooden floors and ceramic tiles, providing that the base is sound, solid, dry and even. Soft floorcoverings such as carpets or carpet underlays should be removed. The underlay should be laid with a suitable tape for the joints; we would normally recommend the use of an underlay that incorporates a vapour barrier or damp proof membrane, used in conjunction with a vapour tape.

Starting in the corner of the room lay the first row of flooring with the tongue and groove or clic-lock system facing the wall, do not forget to allow the required expansion gap. Ensure that the boards are tightly jointed or glued together, using a tapping block or pulling iron. The offcut from the first row can then be used to start the next row, providing it is of an adequate size. To get the best appearance and performance from your floor it is best to stagger the joints by at least 300mm. Never use excessive force and if necessary remove the board and check for debris in the joint.

A perimeter expansion gap will always be required; this can be covered by a scotia moulding or skirting board. 


Nailing down Floors

A traditional tongue and groove wooden floor can be secret nailed over an existing timber sub-floor (subject to it being the required thickness) or fixed directly to joists to provide a finished structural floor. Building regulations require a structural floor to be at least 18mm in thickness. When nailing, the subfloor or batten should be of an appropriate width and thickness to retain a 50mm fixing when fired at a 45 degree angle; normally via a Porta-Nailer or similar machine. Joists or battens should be kiln dried and spaced in accordance with building regulations at approximately 250mm-300mm centres. Where required, a polythene damp proof membrane can also be used beneath the battens or a bitumen backed lining paper can be used over the top, with an overlap of 200-300mm. Flooring should be installed at 90 degrees to the subfloor; fixings should be no more than 400mm apart.  Adhesive should not be used to glue the joints with this method. It is possible to have header joints which are not over a joist providing the boards either side are fully spanning the joists. A perimeter expansion gap will always be required; this can be covered by a scotia moulding or skirting board. Care should also be taken when nailing floors where pipes and services are running underneath.


Sticking Down your Floor

A traditional solid oak board and some engineered boards can be fixed directly to the subfloor with an approved adhesive. These specialised adhesives will hold the boards firmly in place and allow for the necessary expansion and contraction. The adhesive should be applied using a suitable sized notched trowel and spread evenly on the subfloor. It is essential that there is a full bond to each board to ensure maximum stability. We would always recommend that fully adhered floor installations are completed by an experienced tradesman. Never use additional wood glue on the joints when using this method.

A perimeter expansion gap will always be required; this can be covered by a scotia moulding or skirting board.


Important Note: 

Guidelines offer general advice only and are not be used in lieu of the manufacturer’s instructions

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