Builders' Merchants Explained: How They Work & How to Buy

A builders’ merchant is a specialist supplier of construction and building materials, bricks, blocks, timber, roofing, insulation, plasterboard, plumbing goods, drainage and general fixings, that sells primarily to the trade. Unlike a DIY shed, they carry commercial-grade quantities, stock materials that professional builders actually specify, and structure their prices around volume purchasing. That said, members of the public are welcome at virtually every builders’ merchant in the UK, and many homeowners use them for materials, grades and quantities the high street does not carry.

If you are planning a renovation, extension or new build, or managing a project where your contractor is buying materials on your account, it pays to understand how these businesses work.

What a Builders’ Merchant Actually Is

Builders’ merchants sit between manufacturers and end users. They buy in bulk from brick makers, timber processors, insulation factories and plumbing component manufacturers, then hold stock locally so that builders can collect what they need each morning. The model relies on turnover: the merchant earns a margin on every pallet of blocks, sheet of plywood or reel of cable that goes out the door.

The UK market is dominated by a handful of national chains, but there are also dozens of regional independents. National groups include Travis Perkins, Jewson, Buildbase, Selco, MKM Building Supplies and Huws Gray. STARK Group completed its purchase of Saint-Gobain Building Distribution, Jewson’s parent, on 1 March 2023.¹² Grafton sold its traditional merchanting business in Great Britain, including Buildbase, to Huws Gray at the end of 2021.³ Each operates a slightly different model, more on that in the comparison guide, but all share the same fundamental structure: a trade counter staffed by knowledgeable sales people, a yard where heavy goods are held, and a delivery fleet.

Trade Counter vs Yard

Walk into any branch and you will see two distinct areas:

• Trade counter, an enclosed sales desk where you order plumbing fittings, fixings, timber lengths, plasterboard and other goods that are stored in a warehouse behind. Staff pull your order while you wait or have it ready for a specified time.
• Builders’ yard, an open or covered yard where blocks, bricks, aggregates, sand, ready-mix concrete (at branches with batching plants) and landscaping materials are stored on pallets. A forklift operator loads your vehicle or a delivery lorry.

Some larger branches also have a showroom for kitchens, bathrooms or roofline products, and a tool hire counter.

Merchant vs DIY Store

The difference is not just price, it is range, quality and minimum quantities.

DIY stores serve a genuine purpose for weekend jobs, small quantities and convenience. But for structural materials, treated C24 timber, 7.3 N/mm² dense concrete blocks, type 1 MOT stone, 140 mm PIR insulation boards, a merchant is the right source.

Trade Account vs Cash Buying

Most merchants offer two ways to buy:

Cash account (or cash customer): You pay at the point of purchase by card or cash, at whatever price the branch decides to quote you. There is no credit. Any homeowner can do this, just turn up. Prices on a cash account are typically higher than those on a trade credit account, and not always below what DIY retailers charge. In September 2026, for example, Travis Perkins listed a 100 mm dense 7.3 N concrete block at £2.93 retail and £2.54 on a trade account, while Wickes listed a Tarmac 100 mm 7.3 N dense block at £2.40.⁴⁵

Credit (30-day) trade account: A business credit account with monthly billing; Travis Perkins, for example, offers a minimum of 30 days’ interest-free credit up to the account’s credit limit.⁶ Prices are negotiated and often lower than cash rates, especially for high-volume lines. Expect the merchant to take references or run a credit check before opening one. See the dedicated guide on opening a trade account for the full process.

How to Buy as a Homeowner

You do not need a trade account or a VAT registration number to shop at a builders’ merchant. The process is straightforward:

1. Walk in or phone ahead. For large quantities, a full pallet of blocks, a lorry of timber, it is worth calling ahead to check stock.
2. Ask for a price. Prices are not always on display. Tell the counter staff exactly what you need (product, quantity, any specification requirements such as a strength class or fire rating).
3. Compare a couple of branches. Prices vary by branch and by the day. A five-minute phone call to a second merchant can save a meaningful amount on a large order.
4. Pay at the counter. Most merchants accept debit and credit cards. Larger deliveries are sometimes cash or bank transfer only, ask.
5. Arrange delivery or collect. Most merchants offer delivery on a schedule. Delivery costs vary by merchant, order size and distance, and a timed delivery or a HIAB crane offload usually costs more than a standard kerbside drop, so ask for the charge when you order. Travis Perkins, for example, advertises free next-day delivery on orders over £150.⁷

What Merchants Stock That DIY Stores Often Do Not

For any serious project, the range difference matters as much as price. Builders’ merchants routinely stock:

• Structural timber in C16 and C24 graded regularised and CLS sections
• Dense and lightweight concrete blocks in specific compressive strengths (3.5 N, 7.3 N, 10.4 N)
• Facing bricks from multiple manufacturers in a wide colour and texture range
• Roofing battens in BS 5534-compliant sizes⁸
• Breathable roofing membranes and sarking boards
• PIR and mineral wool insulation in full thickness ranges (50 mm to 200 mm)
• Steel lintels (Catnic, IG, Birtley) in sizes not stocked by DIY sheds
• DPC, DPM and cavity trays to BS 6515 and BS 8215⁹¹⁰
• Drainage goods, clay and plastic pipe in 100 mm to 450 mm diameters
• Aggregates, sharp sand, building sand, MOT Type 1, 20 mm gravel, ballast

VAT and Receipts

Builders’ merchants charge VAT at the standard rate (20%) on most goods.¹¹ Energy-saving materials such as insulation are zero-rated until 31 March 2027 (5% from 1 April 2027) when a business supplies and installs them in a home, but a sale of the materials alone is standard-rated, so buying insulation over the counter carries the full 20%.¹² Ask your merchant if you are unsure.

Always obtain a proper VAT receipt. If you are running a renovation on a property that will be sold or let, detailed receipts from the merchant allow your accountant to evidence material costs.

Negotiating at the Counter

Merchants expect professionals to negotiate, and most counter staff have some discretion on price, particularly for larger orders or repeat business. Even as a homeowner buying for a one-off project, it is worth asking: “Is that the best you can do on a full pallet?” or “What if I take ten sheets rather than five?” You will not always get a discount, but you will sometimes.

Some branches will also consider matching a written quote from a nearby competitor, so it is worth asking.