CLS timber — short for Canadian Lumber Standard — is a regularised, smooth-planed softwood section with rounded arrissed edges, produced to consistent dimensions that make it faster and easier to work with on site than traditional sawn carcassing. Its uniform profile and clean finish make it the go-to choice for stud walling, partition framing, and timber frame construction across residential and light commercial building projects throughout the UK.
The most common CLS size is 38x89mm — broadly equivalent to a 2x4 in imperial — though 38x63mm, 38x114mm, and 38x140mm sections are also widely used depending on the structural and thermal requirements of the wall build-up. CLS studs are typically spaced at 400mm or 600mm centres, making it straightforward to calculate quantities from your floor-to-ceiling height and wall length.
CLS timber is ideally suited to dry internal partition walls and studwork in standard residential construction. Its consistent, regularised profile means less time dressing timber on site and a cleaner, more predictable finish — particularly valued on larger framing and housebuilding projects where speed and accuracy matter.
At Nicks Timber, we've been supplying quality framing timber to the trade since 1856. Our CLS range is stocked in the sizes and lengths that builders, developers, and contractors rely on, with the consistent quality and dependable availability that comes from nearly 170 years of timber merchanting.
Order online for delivery, or contact our team for trade pricing and volume requirements.