Most Sussex homeowners only specify a pitched roof covering once in their lifetime. Get the choice right and the roof will outlast you. Get it wrong and you either fail planning, overload the existing structure, or end up with a roof that looks wrong on the property for the next 50 years.
This guide walks through the four materials actually installed on Sussex pitched roofs – clay tile, concrete tile, natural slate, fibre cement slate – and the local factors that push the decision one way or the other. We’ve focused on Sussex rather than trying to write a generic UK guide, because the right answer depends on factors that vary across the country. Sussex has conservation areas, the High Weald AONB, the South Downs National Park, a distinctive vernacular, and BS 5534 Wind Zones that matter for fixing specifications.
If you’re after the general “what is a pitched roof” overview, see our pitched roofs guide. For the lifespan and value angle, see durable roofing materials. This guide is specifically about choosing a material.
The Four Materials You’ll Actually Choose Between
UK roofing has more materials available than Sussex roofs actually use. We’ve deliberately focused on the four options that make up well over 95% of what’s actually installed on Sussex homes.
Not covered: metal roofing (rare on Sussex homes outside contemporary architect-designed projects), thatch (specialist heritage work, Cornerstone doesn’t thatch), Horsham Stone slab roofs (exclusively on listed heritage buildings; specialist conservation contractors only), cedar shingles (not a UK material). If any of these apply to your property, you need a specialist conservation roofer rather than general guidance.
The real choice is between clay tile, concrete tile, natural slate, or fibre cement slate.
Clay Tiles
Clay tiles come in several formats:
- Plain tiles – small, flat tiles laid in overlapping courses. The traditional Sussex vernacular material. Handmade plain tiles are the specification for historic and conservation area properties.
- Pantiles – S-shaped interlocking clay tiles, more common in East Anglia and Sussex coastal towns than inland.
- Peg tiles – older format, handmade, secured by oak pegs rather than nails. Almost exclusively on unrestored historic buildings.
Weight: ~55-65 kg/m² wet for plain tiles
Minimum pitch: 35° for plain tiles, 30° for some machine-made profiles
Typical lifespan: 60-150 years depending on manufacturing method
Concrete Tiles
Concrete tiles come in two main formats:
- Interlocking – large-format tiles with overlapping ribs, the standard on post-war UK housing. Cheaper per m² than any other option.
- Plain – similar format to clay plain tiles, designed to look like clay at lower cost.
Weight: ~45-55 kg/m² wet
Minimum pitch: 17.5-22.5° for interlocking, 35° for plain
Typical lifespan: 50-70 years
Natural Slate
Sourced from Welsh, Spanish, or Brazilian quarries:
- Welsh slate – the premium UK option. Blue-grey, fine-grained, incredibly long-lasting. The original slate on Victorian and Edwardian Sussex properties.
- Spanish slate – dominant in modern re-roofs. Grade T1 is excellent; lower grades vary in quality.
- Brazilian slate – less common, generally lighter in weight and colour, variable quality.
Weight: ~22-28 kg/m²
Minimum pitch: 25-30° typically (depends on size and lap)
Typical lifespan: 75-150 years
Fibre Cement Slate
Manufactured from cement and reinforcing fibres, designed to look like natural slate at lower weight and cost.
Weight: ~18-22 kg/m²
Minimum pitch: 15-20° for larger formats
Typical lifespan: 30-50 years
The Six Sussex-Specific Factors That Should Drive Your Choice
Most of the generic UK roofing guides out there cover material comparisons. What they don’t cover is what actually matters when you’re making the decision on a specific Sussex property. These six factors matter more than general lifespan comparisons.
1. Is Your Property in a Conservation Area?
Mid Sussex has conservation areas in Cuckfield, Lindfield, Hurstpierpoint, Ditchling, West Hoathly, Ardingly, parts of Hassocks, and parts of central Haywards Heath and Burgess Hill. In these areas, Mid Sussex District Council will usually require the replacement roof to match the existing material.
On historic Sussex properties, the original material is almost always clay plain tile (the local vernacular), natural slate (on Victorian or Edwardian properties), or in rare cases Horsham Stone. The council is unlikely to approve a change to concrete tile in a conservation area, even if the existing roof is currently concrete – they may require a return to the original material when you re-roof.
Check before specifying: Search the Mid Sussex District Council planning portal for your address, or call their planning department. A 10-minute check now saves a six-month planning appeal later. On listed buildings, listed building consent is required regardless of conservation area status.
2. Are You in the High Weald AONB or South Downs National Park?
Much of the Cornerstone patch sits inside or adjacent to the High Weald Area of Outstanding Natural Beauty. The AONB covers large parts of Mid Sussex, including most of the villages we serve – West Hoathly, Ardingly, Balcombe, parts of Cuckfield and Lindfield.
The South Downs National Park sits to the south of our core area but extends into parts of the Cornerstone service area (particularly near Hassocks, Ditchling, and the downland villages).
Both designations have planning guidance that expects sympathetic materials. Natural clay tile or natural slate is expected; concrete tile is rarely approved on new roofs in AONB or National Park settings. The rules are applied less strictly than in formal conservation areas, but planning decisions still factor material choice into the assessment.
3. What Is Your Existing Roof Structure Rated For?
This is where we see the most expensive mistakes. Homeowners want to “upgrade” from concrete tile to natural slate, or vice versa, without checking whether the rafters can take the weight change.
The weight order is:
- Natural slate: ~25 kg/m²
- Fibre cement slate: ~20 kg/m²
- Concrete interlocking tiles: ~45 kg/m²
- Concrete plain tiles: ~50 kg/m²
- Clay plain tiles: ~55 kg/m²
Switching to a lighter material (concrete → slate): usually fine. The structure is already over-rated.
Switching to a heavier material (slate → concrete): often needs structural strengthening. On 1950s-1985 concrete-tiled Sussex housing, the rafters were sized for concrete tiles. Upgrading to clay plain tiles can push the load over the design limit.
Switching from a heavier material to anything: check the rafters are still sound. Sometimes “the new roof should be lighter” has to be weighed against “the rafters have been carrying too much weight for 50 years”.
On any re-roof changing the tile material, a structural engineer’s check is worth the small cost – usually £200-400 for a domestic property.
4. What Pitch Is Your Roof?
The existing pitch of the roof constrains the material choice. Each material has a minimum pitch below which it won’t be weathertight.
| Material | Minimum pitch |
|---|---|
| Clay plain tiles | 35° |
| Concrete plain tiles | 35° |
| Concrete interlocking tiles | 17.5-22.5° (depending on profile) |
| Natural slate | 25-30° (depending on size) |
| Fibre cement slate | 15-20° (depending on format) |
A 1960s Burgess Hill bungalow with 22.5° rafters cannot take plain clay or concrete tiles – you’re limited to interlocking concrete, natural slate (in larger formats), or fibre cement slate. A 50° Victorian terrace in Haywards Heath can take anything but is almost always best kept on its original slate.
Pitch-matching is not negotiable. Any roofer recommending a material that violates its minimum pitch is setting up a guaranteed leak within a decade.
5. What Does BS 5534 Mean for Your Re-roof?
Since the 2014-2018 updates, every new slating and tiling installation in the UK must be mechanically fixed – every tile nailed, clipped, or both. Mortar bedding alone is no longer compliant for verges, ridges, or hips on new work.
Sussex sits mostly in BS 5534 Wind Zone 2, with higher elevations (the High Weald ridges, exposed downland plots in the north of the county, coastal positions near Brighton) in Zone 3.
What this means for your choice:
- Higher wind zones require more fixings per tile
- Some interlocking concrete tiles are unsuitable at the highest wind zones
- Dry ridge, dry verge, and dry hip systems are effectively mandatory on new work
- The fixing spec adds to install cost – more significant on larger roofs
See BS 5534 explained for the technical detail.
6. Are You Matching Neighbours or Setting a New Standard?
The simplest rule-of-thumb in Sussex: match the vernacular for the property type and location.
- Victorian and Edwardian terraces in central Haywards Heath: natural slate. Matches the row, matches the period, protects resale value.
- Rural Weald cottages in Cuckfield, Lindfield, Ditchling: handmade clay plain tiles. Vernacular, long-lasting, almost always required in conservation settings.
- Post-war and 1960s-1990s estates in Burgess Hill, Hassocks, parts of Haywards Heath: concrete interlocking tiles. Honest, cost-effective, fits the house.
- Modern new-build developments: whatever the original developer specified. Usually concrete interlocking.
- Bungalows with shallow pitches: fibre cement slate or interlocking concrete, depending on the look wanted.
Deviating from the vernacular usually costs more, can cause planning issues, and often reduces resale value. It occasionally produces a stunning result on a specific project – but it’s a decision to make deliberately, not by default.
Quick Decision Framework
If you’re still unsure which way to go, this framework covers 90% of Sussex pitched-roof decisions:
If your property is period, in a conservation area, or in the AONB / National Park:
Natural clay tile or natural slate. Match what’s already there. Check with Mid Sussex DC before specifying anything else.
If your property is post-war, modern, and not in a designated area:
Concrete interlocking tile is usually the right cost/life trade-off. Natural slate is a premium upgrade for plot-defining properties where you plan to stay long-term.
If you’re converting a flat roof to pitched, or the existing rafters are undersized for the material you want:
Fibre cement slate is the lightweight option. Looks like slate from the ground, weighs half as much, 30-50 year life.
If you’re unsure about structure or conservation status:
Get a structural check and a conservation status check before you commit to any material. Both are cheap insurance.
Getting a Quote That’s Worth Comparing
A roofing quote that lets you compare like-for-like should include:
- Named tile or slate product – not just “concrete tile” but the specific manufacturer and model (e.g., Marley Modern, Redland Cambrian, Cupa Heavy 3 Spanish slate, Welsh Penrhyn slate)
- Specified underlay – BS 5250 classification and manufacturer
- Specified battens – BS 5534 Class A or B, 38 x 25mm minimum
- BS 5534 wind zone and fixing spec for that zone
- Dry ridge, dry verge, dry valley systems named
- Lead code and manufacturer for flashings
- Insulation spec and U-value achieved – Part L
- Scaffold duration and weather cover included
- Waste disposal included
- Clear warranty terms – both manufacturer and workmanship
Any quote missing these details is either hiding the cut corners or is from a contractor who doesn’t specify to the standards. Both are reasons to rule them out.
Before You Commit: Three Practical Steps
- Check your conservation / AONB / listing status with Mid Sussex District Council. A 10-minute call saves months of later trouble.
- Get a structural opinion on the existing roof before you specify a heavier material. £200-400 well spent.
- Ask any roofer to quote against a specific BS 5534 fixing spec and a named tile or slate product – not “matching existing” or “to BS 5534 standard”. Specificity separates real contractors from opportunists.
Get It Right From the Start
The roof is the most important part of the building envelope. Walls can be patched, floors can be relaid, but a roof that fails causes damage to everything beneath it. Whether you end up with clay, concrete, natural slate, or fibre cement, the quality of the specification and install determines whether your roof stays weathertight for decades.
If you’re planning a re-roof and want advice on which material is actually right for your Sussex property, book a free visit. We’ll look at your property, check the structure, cover the conservation and planning status, and recommend the right approach. No pressure, no upsell.