Our specialist stores
Our specialist stores
CLS Timber
This is timber for people who want their frame to behave. For trades who value speed and accuracy. For DIY who do not want to fight warped lengths or rough edges when building stud walls, partitions or clean internal structures. If the job involves framing, studwork or clean structural lines, CLS kiln dried timber is where things usually start going right.
What is CLS kiln dried timber?
CLS kiln dried timber is timber that has been prepared for precision work, not for decoration and not for exposure.
It starts as structural softwood, then goes through a controlled kiln drying process to stabilise moisture before it reaches the site. After drying, the timber is graded for strength and machined to consistent dimensions. Every face is smooth. Every edge is eased. Nothing is left rough or unpredictable.
In UK terms, CLS describes timber supplied in finished sizes for studwork. Most CLS timber is graded C16, which suits the demands of standard internal framing. The focus is not on treatment or appearance, but on accuracy, repeatability and ease of installation.
Kiln drying limits movement once the timber is fixed in place. Sections stay straighter. Spacing stays consistent. Fixings sit cleanly. The smooth, planed finish makes CLS easier to handle, faster to work with and better suited to builds where alignment matters from the first stud to the final board.
What is CLS timber used for?
Its main role is internal studwork. Wall frames, partitions, service voids. The hidden structure that keeps plasterboard straight and doors aligned. This is classic stud timber and studwork timber, chosen because it stays consistent from length to length.
CLS is also widely used for internal framing in renovations. Boxing in pipes and ducting. Creating alcoves, media walls and built-in storage. Anywhere the frame needs to stay square, so the final finish looks clean.
Inside garages, workshops and utility rooms, CLS timber is used for shelving frames and workbenches. It suits storage systems that need to stay square and easy to fix. Measurements line up. Cuts stay clean.
CLS timber is also used in loft conversions and internal stair structures. Straight lengths make spacing predictable. Installation is quicker. Finishing problems are kept to a minimum.
CLS timber is not designed for external exposure or damp environments. It is chosen for dry, internal spaces, where controlled moisture content and clean edges save time, reduce waste and make the build feel easier from the first fix to the final board.
CLS timber in this range is supplied in a 38mm width, with hight options of 63mm and 89mm. It is graded C16 and available in the common imperial sizes 3×2 and 4×2. Available lengths are 2400mm and 3000mm. For internal use in dry conditions only.
Benefits of CLS C16 timber
- Straight, consistent lengths that line up easily during framing.
- Predictable strength for standard internal structural work.
- Kiln dried to reduce movement after installation.
- Softened edges for safer, more comfortable on-site work.
- Easy to measure, mark and fix without constant adjustment.
- Helps keep stud walls square and plasterboard flat.
- Ideal for dry, internal spaces where accuracy matters.
Why choose our CLS timber?
CLS timber is not a decorative choice. It is bought when dimensions need to match, cuts need to stay clean, and the frame must hold its line once fixed.
At Sheet Materials Wholesale, CLS timber is supplied with that expectation in mind. Consistent sections. Clear grading. Stock that is ready to ship, not promised later.
Pricing is structured for practical buying. Single lengths when needed. Bulk and pallet quantities when the job scales up. Trade discounts apply, and value for money stays consistent across order sizes.
All material is held in UK stock. Fast nationwide delivery is available, including next-day delivery on selected products. Orders are delivered kerbside to the site or home, depending on access and project needs.
The buying process stays simple. VAT invoices are provided as standard. Order tracking is available from dispatch to delivery. Quotes are issued promptly, keeping decisions simple and direct.
At Sheet Materials Wholesale, you can purchase CLS Timber at low wholesale prices with fast nationwide delivery for most of items within 1-3 working days across the UK. Next-day delivery is also available on most orders. Competitive rates guaranteed.
FAQ
Where to buy CLS timber?
You can buy CLS timber online from Sheet Materials Wholesale, with UK-held stock available for both trade and DIY customers. Sizes, pricing and availability are shown clearly online, with delivery direct to the site or home.
What is CLS timber treated with?
CLS timber is not pressure treated. It is kiln dried, strength graded and planed all round with eased edges. The drying process controls moisture content but does not add any chemical treatment.
Can CLS timber be used outside?
No. CLS timber is designed for dry, indoor spaces. It does not handle moisture or outdoor exposure. Treated timber should be used outside.
How to fix CLS timber for studwork?
CLS timber is fixed with standard wood screws or nails. Measure, level, and fix the frame in place as you go. The straight, planed sections make it easy to keep stud spacing and alignment consistent.
CLS Timber Range
Showing all 4
Products in CLS Timber
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Buy in Bulk & Save
168-335 336+ £2.97£3.56 £2.91£3.49 
38 x 63mm CLS Sawn Timber C16 Graded (3” x 2”) 2400mm
C16 CLS 3×2, is kiln-dried for controlled moisture and straightness. Sanded all round with soften edges on the timbers for less risky and easier operations. CLS 38mm x 63mm is reliable for stud walls, overall wall framing and floor lining, stable and ready for a variety of both; non-structural and structural use.
£3.06£3.67 Ex VATInc VAT£1.28£1.54 Per M Add to cart -
Buy in Bulk & Save
224-447 448+ £3.83£4.60 £3.75£4.50 38 x 63mm CLS Sawn Timber C16 Graded (3” x 2”) 3000mm
C16 CLS 3×2, is kiln-dried for controlled moisture and straightness. Sanded all round with soften edges on the timbers for less risky and easier operations. CLS 38mm x 63mm is reliable for stud walls, overall wall framing and floor lining, stable and ready for a variety of both; non-structural and structural use.
£3.95£4.74 Ex VATInc VAT£1.32£1.58 Per M Add to cart -
Buy in Bulk & Save
224-447 448+ £3.94£4.73 £3.82£4.58 
38 x 89mm CLS Sawn Timber C16 Graded (4” x 2”) 2400mm
C16 CLS 4×2, is kiln-dried for controlled moisture and straightness. Sanded all round with soften edges on the timbers for less risky and easier operations. CLS 38mm x 89mm is reliable for stud walls, overall wall framing and floor lining, stable and ready for a variety of both; non-structural and structural use.
£4.15£4.98 Ex VATInc VAT£1.73£2.08 Per M Add to cart -
Buy in Bulk & Save
224-447 448+ £4.95£5.94 £4.79£5.75 38 x 89mm CLS Sawn Timber C16 Graded (4” x 2”) 3000mm
C16 CLS 4×2, is kiln-dried for controlled moisture and straightness. Sanded all round with soften edges on the timbers for less risky and easier operations. CLS 38mm x 89mm is reliable for stud walls, overall wall framing and floor lining, stable and ready for a variety of both; non-structural and structural use.
£5.21£6.25 Ex VATInc VAT£1.74£2.09 Per M Add to cart