7th Dec 2022 -

8x2 timber is a strong option, typically used within joists and supports. In this guide from Building Materials Nationwide, we’ll explain the essentials of 8x2 timber, including the size it’s sold in, how it can be bought, and the main uses within the UK.

How Will 8x2 Timber be Sold in the UK?

While 8x2 continues to be the informal term used for most purchases of timber, within the UK products must be sold in metric sizes rather than imperial, such as mm. This means that when looking, either online or within a shop, you’ll be seeing the size 200mm x 50mm instead. This is essentially the same as 8x2 (a truly accurate measurement would be 203.2mm x 50.8mm) and will be the closest equivalent sold within the UK. When purchasing anything except green timber, it’s worth remembering that the actual size will be smaller.

The Actual Size of 8x2 Timber

The nominal size of timber is the size it is originally rough sawn to, and the size that will be listed on the product specifications. However, rough-sawn green timber will be largely unsuitable for most construction uses, due to its high moisture level and uneven surfacing. Most timber sold within the UK will have been kiln-dried, a process designed to take moisture levels below 20% and aid use within construction. Planing may also be used for certain types of 8x2 timber, a process that is essentially sanding to create a smooth surface. Both drying and planing will reduce the size of the timber beam below the nominal one. This means that the size of an 8x2 timber beam within the UK is likely to be around 184mm x 38mm.


What Lengths is 8x2 Timber Sold in?

The lengths that 8x2 timber is sold in will vary considerably, with increments of 30cm or 60cm commonly used. Within our structural timber range, you’ll find 8x2 timber in 2.4m, 3m, 3.6m, 4.2m, and 4.8m.

What Finishes is 8x2 Timber Available in?

When you purchase 8x2 timber, it’s likely to at a minimum be kiln-dried, with green timber only used for specialist purposes. There are other finishes available within the UK, each suited to specific installations.

Pressure Treated

Kiln-dried softwood timber will be at risk of moisture and insect damage when installed externally. A solution to this is to use pressure-treated timber, which will have been coated in preservatives allowing it to withstand moisture. Rainwater or moisture content within the soil can cause rot and decay within the timber, and insect burrowing can cause both visual and structural damage. When looking to use 8x2 timber externally, you should opt for pressure-treated beams.

C16 and C24

Softwood timber can be strength-graded, proving its suitability to be used within load-bearing construction. C16 and C24 are the commonly used grades within the UK, with C24 being the stronger of the two. If looking to use an 8x2 timber within any load-bearing construction elements you will need to opt for a strength-graded option, as otherwise you will have no way of knowing the strength of the wood.

PSE 8x2 Timber

PSE timber stands for planed square edge timber. Planing timber involves sanding it to create an attractive and flat facing. This can be performed on one or more faces of a timber beam. PSE timber will have been planed on all faces, with sharp corners between each. Planed timber is needed in any aspect of construction where the wood will either be visible or touched, with rough-sawn timber having an unappealing look and risking splinters to those who come into contact with it.

Need Quality Timber For Your Next Project?


    • Ideal for general construction, fencing, garden and leisure timber applications
    • Pressure-treated
    Price from: £10.28 £12.34

    • Ideal for general construction, fencing, garden and leisure timber applications
    • Pressure-treated
    Price from: £10.28 £12.34

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What Are the Popular Uses of 8x2 Timber?

Within construction, timber is a hugely malleable material, allowing itself to be used in a large variety of constructions. That being said, there are a couple of specific tasks where 8x2 timber will be more widely used.

Floor Joists

Depending on the foundations of your house you may need wooden joists within its construction. In suspended wooden floors, found within most older houses, you’ll need to construct a sturdy set of joists onto which the entirety of the floor can be fitted. 2x8 joists, when graded to C16 or C24, will offer a suitable level of strength, ensuring that the floor within your house is well supported. As floor joists are not visible, you can use rough-sawn timber.

Flat Roof Joists

Flat roof joists will also make for a vital part of the construction, holding the layers of the roof in place. This means that using graded timber is preferable. Moisture resistance can also be important within a flat roof, due to the elevated threats of moisture within the roof space. This means that using a strength-graded, pressure-treated timber may be preferable, for those looking to avoid risks within their roof.

Our Range of Timber For Sale

Building Materials Nationwide aims to remove the hassle that can come from sourcing building supplies. Within our website, you’ll find a suite of timber options, including treated and structural 2x8 timber, all of which can be delivered across the UK, all at competitive prices. To make the most of our service, our customers within the industry can sign up for a trade account. Trade account holders gain access to their own dedicated account manager, our full range of building supplies, and lightning-fast nationwide delivery. Sign up for a trade account today.