Flooring Glossary - An A-Z of flooring terms











Purchasing a new wood floor can be daunting, not least because of all the jargon that comes along with it. From acclimatisation to warping, read our guide to get your head around some of the more tricky terminology and take the stress out of your buying journey.


AC Rating


AC Rating is also known as ‘abrasion class’ and it’s a method of rating laminate flooring based on its durability. The ratings range from AC1 to AC5, with AC1 boards being suitable for residential spaces with low foot traffic, and AC5 is suitable for commercial spaces such as shops with high foot traffic.




This is the process of leaving the wood floor in the area you are going to install it for a few days. It allows the natural moisture content of the wood to adjust to the surrounding conditions and helps to stop buckling, swelling and gapping after installation.

Wood acclimates most successfully when it is stored at the same temperature and humidity as the room it is going to be laid in. It is recommended that planks are left to acclimate for at least three days.




Sticky paste or glue used for attaching the flooring to the subfloor. The best adhesives are flexible and allow the wood floor to move a little depending on the natural variations in humidity.




Beading is a wood flooring accessory that is used to cover up gaps around the edge of a room between floorboards and skirting. The gaps are necessary to leave room for expansion, otherwise your floor may bend or buckle. Beading covers the gaps to ensure your floor looks neat and finished.




A form of damage that can happen to wood flooring. Rather than being flat, the plank curves inwards or outwards to create an uneven surface.




A more serious type of damage than bowing, where boards pull up from the floor, sometimes by several inches. Usually caused by excessive water damage.


Care and maintenance


A crucial part of wood floor ownership where the owner uses the correct materials and methods needed to ensure their floor lasts for a long time.


Chevron is the most commonly used pattern for parquet flooring. Short boards are laid together to form a line of ‘V’ shapes. Once all the boards are fitted, the pattern becomes a series of stylish, uniform zigzags.


Click flooring


A modern fitting method usually seen on laminate flooring. It allows two boards to fit and ‘click’ together, making it easier for non-professionals to lay their own floors.




Damage to the boards causing them to become convex in appearance. Usually caused by excessively damp atmospheric conditions whilst the subfloor remains dry.




The opposite of crowning and more commonly experienced. It is caused by moisture in the subfloor pulling the bottom of the board downwards, making the edges rise above its centre.



Damp proof membrane


A layer of material that is fitted between the flooring and the subfloor to prevent moisture causing damage. Many underlays come with a built-in damp proof membrane.




The process of causing slight damage to wood flooring so that it has a fashionable worn look. The damage caused is very superficial and doesn’t affect the longevity of the boards.


Engineered wood flooring


A type of flooring composed of several layers of plywood or high-density fibreboard layered together to form a plank, with a solid wood layer on top. This type of board is stable enough to cope with changes in temperature and humidity.

The solid wood layer is called the ‘wear layer’. The wear layer can vary in thickness from as little as 2mm to as much as 6mm. The thicker the wear layer, the more sturdy your floor boards are and the longer they will last.

Expansion Gap


The expansion gap is the space left at the edges of a wood floor when it has been fitted. Wood can naturally expand and grow and the expansion gap allows enough space for this to happen without the boards being damaged.





This describes the final coating of the wood that gives it its overall look, usually done with oil, lacquer or varnish. The finish will give it a matt or shiny look and can have a coloured tint.

Floating floor


One of the main installation methods for wood flooring, a floating floor isn’t glued or nailed down but is left unattached to the subfloor when fitted.

Forest Stewardship Council (FSC)


The Forest Stewardship Council (FSC) is a global, not-for-profit organisation that promotes responsible forest management worldwide. The FSC system allows customers and businesses to purchase wood, paper and other products made with materials from properly managed forests or recycled sources.



Glue down floor


Glue down installation uses an adhesive to firmly fix wood flooring to the subfloor. Most commonly used with solid wood flooring.





The naturally occurring lines in wood that give it character and uniqueness. Laminate flooring has grain artificially created to make it look more authentic.


High Density Fibreboard

HDF is made of wood fibres that are compressed to make a solid wood core. It is often referred to as hardboard and is primarily used in engineered wood and laminate flooring products.




Usually found in kitchens and bathrooms and a very important factor to consider when fitting a wood floor. Too much moisture in a room can cause damage to a wood floor.





A layer of material that is usually built into the subfloor to provide a barrier for heat and noise.




A wooden strut used to support a floor to which the boards are usually nailed.





Timber used to make wood flooring is usually dried in a kiln to reduce its moisture content to below 10%. This level is chosen because it’s the moisture content wood flooring usually assumes in buildings in the UK.


The turn of a staircase is sometimes called the ‘kite’. It is usually found at the top or bottom of the staircase in domestic settings.




Knots are imperfections in the grain of wood where a branch once grew. Minor knots are often attractive and add character to a wood floor.





A clear or coloured varnish used to seal a floor, producing a hard, durable finish that can be further polished if required.




A multi-layered man made flooring product fused together in a lamination process with a printed image on the top to give the appearance of wood.




Maintenance refers to the various methods of looking after your wood floor to ensure and promote its longevity. Some of these include cleaning, repairing and protecting with re-finishing or polishing.


Matt finish


A matt finish makes wood flooring look non-reflective and therefore more natural. Highlights the wood’s colours and shows scratches less than gloss finishes.

Moisture Content

Moisture content is generally referred to in relation to the wood itself, or the subfloor that the wood is going to be laid on top of. It is usually given as a percentage and can be found using a special measuring device called a wood moisture meter.

Multi-use Profiles

Multi-use profiles are accessories that provide a smooth transition between rooms. They can be used for floors that are slightly different heights as well as floors that are the same level.



Nail down installation


A simple and effective method of fixing down a wood floor, but one that can be time-consuming.

Nail down flooring requires a wooden subfloor for it to be attached to. If you have a concrete subfloor, using adhesive to glue your flooring is recommended instead of nailing. Floor fitters use a technique called ‘secret nailing’ which means that the nails are invisible.




Commonly used on stairs with wood flooring, nosing hides corners where planks join, creating a smoother finish.






A method of finishing a floor that offers protection and moisture resistance whilst still allowing the wood to breathe.



Parquet flooring


Parquet flooring is usually laid in a herringbone or chevron pattern to create a stylish look and usually made from solid or engineered wood.


A prefinished hardwood floor is finished at the factory rather than onsite. This means that once it is fitted it doesn’t need to be oiled, waxed, varnished or lacquered as that process has already happened. Pre-finished boards can be much more convenient than boards that have to be finished in situ, as there is less mess and you can walk on the floor immediately.

Pull Bar

A pull bar is used to pull each floorboard snugly up to the next one to ensure a secure fit and make sure the floor looks as neat and properly finished as possible.



Quadrant beading

Used in flooring next to skirting boards to cover the allowed expansion gap (which enables the flooring to expand and contract as necessary).

Quarter Round

Similar to beading, a quarter round is used to cover up the expansion gap round the edge of a floor which is necessary for the floorboards to be able to naturally expand and contract. The quarter round is attached to the skirting instead of the floor boards and is so named because it looks like one quarter of a circle.



Radiant Floor Heating System

A heating system that is located in the subfloor beneath a wood floor and heats a room from the ground up. The best type of floor to use with a radiant floor heating system is a floating floor, as the boards are locked to one another instead of being nailed or glued to a subfloor.



Floorboards that have been used previously and have a pleasantly worn or distressed look.


If your floor ages, fades or becomes damaged in some way it can be refinished to return it to looking like new. Refinishing involves taking the current finish off the floor, sanding it and re-applying a new finish to enhance its appearance.



Usually refers to the grade of the timber being used in flooring. Rustic grades tend to have more colour variation, splits and other features.





A process which removes the top layer of a wooden board, creating a smooth surface for finishing. Boards can be sanded and refinished multiple times.




Physical examples of how a wood floor looks which can be sent to your home so you can see how it might look in situ.


A finishing accessory that is used to cover the expansion gap between the edge of the floor and the skirting board. Also known as beading.




Screed is usually made of sand mixed with cement and is used to level a concrete subfloor before a wood floor is fitted.

Solid wood flooring

Solid wood floors are made from a solid piece of timber as opposed to layers used in engineered wood floors. The floorboards are cut from a single piece of wood.


The subfloor is the surface on which a wood floor is fitted. It is usually made of concrete or wood.


Tapping Block

A tapping block stops the floor being damaged whilst it is being fitted. Each board must be hammered to the next in order to ensure a snug fit. The tapping block goes between the hammer and the board to prevent dents or splits occurring.


Threshold strip


A piece of shaped wood placed in a doorway so that floors of different heights can be smoothly and finished together.


Tongue and groove

A method of fitting boards together to create one continuous floor. A protruding edge, or tongue, is slotted into a groove on the adjacent plank.




Underfloor heating


Underfloor heating is compatible with some types of wood flooring but you should always ask your flooring provider before going ahead and laying the boards.


Underlay can be fitted between the subfloor and the wood floor. It protects the floor by reducing wear and acts as a shock absorber to increase comfort. It can also serve as insulation for both sound and warmth.




Wooden boards that haven’t been varnished or lacquered prior to fitting. A good choice for people who wish to stain or oil their floor themselves.




Veneer is a layer of solid wood found on engineered wood floors. It is decorative and also adds protection to the engineered core beneath.





Damage and distortion caused to wood flooring, usually by excess moisture or fluctuating temperatures.


Wear layer


The top layer of a wooden board which receives the most foot traffic. The quality and longevity of an engineered wood floor depends on the thickness of the wear layer, which can range from 0.6mm on low quality boards up to 6mm on high quality ones.

Wood Species

Wood species refers to the specific type of tree your wood floorboards are made of. Different species have different colouring, hardness and grain patterns, all of which can have a real effect on the look and feel of the floor.

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