Aaron Wright, head of infrastructure data at RICS, looks at roofing costs
The roofing market has fared well in recent years, following a slowdown in 2012/13. Tiles account for around 40% of the market by value, with concrete the largest sub-sector in both value and volume, closely followed by clay. Fibre cement and natural slates have far smaller market shares. Welsh slate, cheap in the 19th century, is now one of the most expensive options. Metal sheet roofing is almost as large in value terms as roof tiles. Applied and flexible membrane has the smallest market share in terms of value and volume but is increasing year-on-year.
Green and brown roofs are becoming popular as they can provide amenity for building users, create visual impact and foster wildlife habitats. Intensive green roofs require a depth of soil to grow larger plants and are labour intensive. Extensive green roofs are designed to be virtually self-sustaining and low maintenance. Brown roofs use local soils and recycled materials as a growing medium. Emerging technologies, which combine roofing materials with renewable energy solutions, such as Tesla’s solar tiles, may ultimately prove cheaper and more resilient than traditional options.
A roof is typically a major capital investment. Replacement is usually required every 20-30 years, but this varies. Factors for consideration when deciding on roofing are capital cost, life expectancy, maintenance, weight (structural support), and appearance. A roof’s enemies are largely natural, which should be borne in mind when making a choice.
These guide prices, as of 2Q17 for a UK mean location, are from the BCIS of RICS. They are based on a medium-sized residential project for products in the low to upper-middle specification range. They assume a pitch of between 35° and 49° unless specified.
Cladding coverings (sloping area measured) – Range £/m2
Sheet roofing
Natural finish, corrugated fibre cement to BS EN 492; single skin covering, inc ancillary items: profile 3/profile 6 £34-39/m2/£29-33/m2
Acrylic finish, corrugated fibre cement to BS EN 492; single skin covering, acrylic finish, inc ancillary items: profile 3/profile 6 £40-46/m2/£37-42/m2
Plastisol coated steel composite roof panel fully bonded; coloured topside, white soffit, 1000mm cover x 80mm thick core, inc ancillary items £67-77/m2
Polyester powder coated aluminium composite roof panel fully bonded; coloured topside, white soffit, 1000mm cover x 80mm thick core, inc ancillary items £59-68/m2
Slate and tile roofing
Concrete tiles; single interlocking, perimeter and alternate courses fixed; 38 x 25mm treated sawn softwood battens and breathable sarking felt, inc ancillary items
Ludlow Major £24-28/m2
Mendip £25-28/m2
Modern £25-29/m2
Wessex £32-37/m2
Interlocking resin slate tiles, perimeter tiles mechanically fixed; main body not; 38 x 25mm treated sawn softwood battens and breathable sarking felt, inc ancillary items; Cambrian £74-85/m2
Plain tiling; 265 x 165mm tiles laid with maximum 100mm gauge and minimum 65mm lap; every fifth course and all perimeter tiles fixed; 38 x 19mm treated sawn softwood battens and breathable sarking felt, including ancillary items
Concrete / Clay / Hand made clay £75-86/m2 / £88-101/m2 / £136-156/m2
Fibre cement slates, 90mm lap, 38x25mm sawn softwood treated battens and breathable sarking felt, including ancillary items 600 x 300mm / 500 x 250mm £35-41/m2 / £46-53/m2
Natural slates, 90mm lap, 38 x 25mm sawn softwood treated battens and breathable sarking felt, including ancillary items
600 x 300mm good quality salvaged £44-51/m2
500 x 250mm good quality salvaged £58-66/m2
400 x 200mm good quality salvaged £100-115/m2
600 x 300mm imported £52-60/m2
500 x 250mm imported £72-83/m2
400 x 200mm imported £119-137/m2
600 x 300mm best quality Welsh £110-126/m2
500 x 250mm best quality Welsh £90-103/m2
400 x 200mm best quality Welsh £124-142/m2
Metal sheet coverings
Milled lead sheet BS EN 12588; fixing with tinned copper clips, brass screwed and copper nails, laid on sheathing felt with patination oil finish, including ancillary items
Code 4, flat / dormer / vertical £147-169/m2 / £237-273/m2 / £259-297/m2
Code 5, flat / dormer / vertical £237-273/m2 / £258-297/m2 / £259-297/m2
Code 6, flat / dormer / vertical £180-207/m2 / £258-297/m2 / £259-297/m2
Traditional sheet copper roofing in 0.6mm copper to BS EN 504 material C107, Temper grade 0, fixing with copper cleats laid on sheathing felt, inc ancillary items
Flat roof with standing seam / batten roll £192-221/m2 / £201-231/m2
Dormer with standing seam / batten roll £242-279/m2 / £256-294/m2
Vertical with standing seam / batten roll £252-290/m2 / £252-290/m2
Plain sheet zinc roofing, BS EN 501; Zinc gauge 14 laying to roll and cap system, laid on sheathing felt, including ancillary items
Flat roof / dormer with standing seam £160-184/m2 / £166-191/m2
Liquid applied and flexible membrane roof covering
Mastic asphalt BS 6925, black sheathing felt isolating membrane weighing 17 kg per roll with 50mm lapped joints, laid loose
20mm Two coat work, solar reflective paint finish £54-62/m2
20mm Two coat work, finished with 300x300x8mm tiles £133-153/m2
Three layer felt coverings to falls and crossfalls and to slopes not exceeding 10˚, first layer BS EN 13707, type 3G perforated; intermediate layer and top layer
Mineral surfaced £60-70/m2
Limestone chippings £67-70/m2
Solar reflective paint finish £77-89/m2
300 x 300 x 9mm fibre cement tiles as finish £184-212/m2
Green roofs
Three categories assume a pitch which does not exceed 10˚
Intensive / semi-intensive / extensive £175-210/m2 / £165-190/m2 / £140-180/m2