Roofing is one of those trades where buying materials from the right supplier makes a substantial difference — both on cost and on product quality. General builders’ merchants carry basic roofing lines, but a specialist roofing merchant offers a far deeper range, genuinely competitive trade pricing, and counter staff who understand the technical differences between products. This guide explains how roofing merchants work, what they stock, and how to get the best deal on a re-roofing or new-build project.
What Specialist Roofing Merchants Stock
A roofing merchant’s stock goes considerably beyond the couple of tile ranges and a roll of roofing felt you’ll find at a general builders’ merchant. Expect to find:
- Concrete and clay roof tiles — from economy concrete interlocking tiles through to premium hand-made clay plain tiles, in a wide range of profiles and colours
- Natural and fibre-cement slate — Spanish, Welsh, Brazilian, and Chinese natural slates in multiple sizes; fibre-cement alternatives (Marley Eternit, Cembrit, etc.)
- Flat-roof systems — EPDM rubber membranes, GRP (glass-reinforced polyester) fibreglass systems, modified bitumen (torch-on felt), liquid-applied coatings, and warm-roof insulation boards
- Roofing underlays and membranes — breathable membranes, vapour control layers, self-adhesive systems
- Leadwork — milled lead sheet in Code 3–6, code strip rolls, lead flashing systems
- Accessories — hip and ridge tiles, verge units, dry-fix systems, mortar, eaves ventilation, soffit and fascia, rooflights, and skylights
- Flat-roof drainage — outlets, gutters, and scuppers for flat and green roof applications
Larger branches of merchants such as SIG Roofing (one of the UK’s largest specialist networks), Roofbase, and independent regional roofing merchants stock most of these categories. General builders’ merchants carry tiles and basic felt but rarely flat-roof systems or the full accessory range.
Trade vs Retail Pricing
The price gap between buying roofing materials from a specialist merchant versus a general DIY shed is among the largest of any building product category, particularly on tiles and flat-roof systems:
| Product | DIY Shed / online retail (approx. inc. VAT) | Trade merchant (approx. ex-VAT) | Indicative saving |
|---|---|---|---|
| Concrete interlocking tiles, per 1,000 | £450–£650 | £280–£420 | 25–40% |
| Spanish natural slate (400×200 mm), per 1,000 | £900–£1,400 | £600–£950 | 20–35% |
| Breathable roofing underlay, 50 m roll | £35–£55 | £18–£30 | 35–45% |
| EPDM flat-roof membrane, per m² | £8–£14 | £5–£9 | 30–40% |
| Code 4 milled lead, per m² | £75–£100 | £55–£75 | 20–30% |
Figures are approximate illustrative ranges. Lead and natural slate prices fluctuate with commodity and exchange rates.
Trade accounts and higher volume orders push prices toward the lower end of these ranges. On a typical re-roofing job — say 80–100 m² of tiling — the difference between buying from a DIY shed and a trade merchant with an account can amount to several hundred pounds.
Tiles, Slate, and Membranes: What to Know Before Ordering
Tiles and slate are sold by the 1,000 (sometimes by the square metre for larger-format products). Always calculate your tile requirement using the tile manufacturer’s specific coverage figure — it varies significantly by tile size and pitch. A roofing merchant’s counter staff can calculate this for you if you give them the roof area and pitch angle.
Order tiles by the full-pack quantity wherever possible. Manufacturers supply tiles on wooden pallets in set pack sizes (often 150–600 tiles per pallet depending on tile size). Ordering a partial pallet attracts a surcharge and, more importantly, means you can’t guarantee the tiles will be from the same batch — colour and tone variation between batches is a real issue with both concrete and clay products, and matching at a later date is notoriously difficult.
Wastage allowance: a standard 10% overage is conventional for plain tiles and natural slate, where cutting loss is higher. For interlocking tiles on a simple pitch with few hips and valleys, 7–8% may suffice. For complex roofs with multiple penetrations (chimneys, dormers, skylights), increase to 12–15%. Return unopened packs within the merchant’s return window rather than over-ordering freely — most merchants accept full-pallet returns in saleable condition within 28–60 days.
Breathable membranes (underlay): BS 5534 requires roofing underlay to meet a minimum low-resistance classification for pitched roofs. Most breathable membranes sold at roofing merchants comply, but economy products from general online marketplaces sometimes do not. Check that any underlay you specify carries EN 13859 classification or is listed on the NHBC or equivalent approved products list.
Bulk Ordering and Delivery
Roofing materials are heavy and awkward. A pallet of concrete interlocking tiles weighs around 1,000–1,500 kg depending on the tile size. Delivery logistics need planning:
- HIAB (crane-off) delivery is standard for palletised tile orders — the lorry crane lifts pallets directly onto a scaffold platform or flat ground. Confirm your site can accommodate the lorry and crane reach
- Delivery charges vary: free above a threshold (often £500–£1,000 trade order value), or £60–£150+ for smaller drops or crane-off with tight access
- Lead times: standard concrete tiles are typically 1–5 working days; clay handmade tiles and some natural slates may need 2–4 weeks, especially for less common profiles or colours. Order early and check stock availability before committing your programme
If you need a mix of materials — tiles, battens, underlay, ridge, and dry-fix accessories — getting them all from one merchant in one delivery saves multiple delivery charges and simplifies logistics considerably. Ask the merchant to consolidate.
Comparing Merchants and Getting the Best Price
For any roofing project of meaningful scale, it’s worth getting two or three quotes. Prepare a materials schedule: tile type and quantity, underlay quantity, ridge/hip specification, dry-fix or mortar accessories, leadwork quantities. A detailed list allows merchants to quote like-for-like rather than substituting cheaper equivalents that may not be equivalent at all.
| Merchant Type | Strengths | Things to Check |
|---|---|---|
| Specialist roofing merchant (SIG, Roofbase, independents) | Widest range, technical expertise, trade pricing | Stock availability on specific tile type/colour |
| General builders’ merchant | Convenient if buying mixed load | Narrower tile range; rarely stocks flat-roof systems |
| Tile manufacturer direct | Sometimes better pricing on large volume | Usually only own product range; min. order quantities |
| Online roofing supplies | Easy price comparison | Check BS/EN compliance; delivery damage risk on heavy items |
Don’t overlook regional independents — in many parts of the UK, a family-run roofing merchant that’s been trading for 30+ years will have manufacturer relationships that give them pricing competitive with national chains, plus local delivery knowledge that national networks can’t always match.
VAT is charged at 20% on all roofing materials. If you’re a VAT-registered contractor, you’ll reclaim this; homeowners cannot. Make sure any comparison between quoted prices accounts for whether the figures include or exclude VAT.
