Slate Roofing near you

BS 5534:2014+A2:2018 is titled Slating and tiling for pitched roofs and vertical cladding. Code of practice, and it gives recommendations for the design, performance and installation of pitched roof coverings using slates, tiles, shingles and shakes and their associated components, for new construction and for standard re-roofing. It expressly does not cover the structural design of the roof itself, and it notes that it may not suit projects using traditional or reclaimed materials — which is a real caveat on a Victorian re-slate.

The A2 amendment revised the structural stability guidance to reflect current knowledge on wind loads and uplift resistance, expressed through the Eurocodes with revised safety factors, updated the worked examples of wind uplift and fixing calculations, and brought in wind uplift resistance for self-supporting underlays. The change homeowners actually see is the one quoted above: reliance on the tensile strength of mortar bedding to resist wind uplift has been withdrawn. Mortar may still be used as a bedding material; it is no longer treated as what holds the ridge on.

So when a roofer offers a dry-fix ridge or a mechanically fixed verge, that is not an upsell, it is the current code of practice. What is worth asking is what the calculation was based on: exposure, roof pitch, the height of the building and the site all feed into how many of the slates need clipping or double-nailing, and a contractor who can explain that is quoting from the standard rather than from habit. Approved Document C adds the plain building-regulations version of the same duty for England: each sheet, tile and section of roof should be fixed in an appropriate manner.

Nail sickness is the classic. The nails corrode where they sit in the slate hole and in the batten, and the slate is then held only by friction until a gale lifts it. The pattern to look for is slates slipping in ones and twos across a whole slope over a few years rather than one slate going after a storm, and slates that come off with no nail left in them. Once it is general, re-fixing individual slates is buying time rather than fixing anything.

Delamination is the slate itself giving up. Water gets between the layers, freezes and splits them, and the slate goes soft, flaky and sometimes visibly curled at the tail. It is far more common on some imported and lower-grade material than on good Welsh slate, and it is one of the few failures where the slates genuinely cannot be re-used. Tapping a slate that rings rather than thuds is the traditional field test a roofer will do on the scaffold.

Then there is everything around the slate. Battens too soft or too thin to hold a fixing, underlay perished to dust so that any water getting past the covering lands on the ceiling, mortar-bedded ridges that have lost their bedding, lead valleys and soakers fatigued or laid in lengths too long for the metal to move, and verges pointed hard and cracked. Most slate roofs are replaced because of these rather than because the slate has worn out.

The option that surprises homeowners is stripping the roof and putting the same slates back. Where the slate is sound and only the fixings, battens and underlay have failed, a roofer can strip the slope, sort the slates into re-usable and scrap, renew the battens and underlay, and re-lay the original material with new fixings, buying in salvage to make up the shortfall. It keeps the appearance of the building, it is often the only acceptable answer on a listed building or in a conservation area, and it avoids sending a century of good material to a skip.

Full replacement earns its place when the slates are delaminating generally rather than locally, when the sorting yield would be so low that the salvage cost outweighs new material, when the roof structure needs work anyway, or when the building is not one where appearance constrains the specification. It is also the moment when insulation and ventilation can be improved, which is a large part of the value of doing it once properly.

The decision is best taken from the scaffold, not the ground. Ask for a sample area to be stripped and sorted before the whole roof is committed, and ask for the yield in writing: what proportion of the slates came off re-usable. That single number decides both the specification and the price, and a contractor who will not give it has not looked.

A slate quotation is only comparable if it names the slate. That means the type and origin, the size, the nominal thickness and the grade, and whether it is new or reclaimed. Two quotations for the same roof can differ enormously on material alone and look identical on paper if both say slate.

Then the things nobody sees. The fixing specification and whether any slates are being clipped or double-nailed, the batten size and grade, the underlay type and whether it is self-supporting, the lead code and the lengths used at valleys, abutments and around the chimney, how ridges, hips and verges are being secured now that mortar alone will not do it, and how the eaves and ridge ventilation is being provided. Ask for photographs from the scaffold at strip, at underlay and at completion, because the underlay and the leadwork are invisible the moment the slates go back on.

Finally, the paperwork. Where the work crosses into notifiable building work the certificate matters to a future buyer's solicitor, so it should be filed with the deeds. Ask whether any guarantee is insurance-backed so that it survives the firm, and what it excludes — most exclude storm damage and anything attributable to the structure below.

Slate is priced on the material and on the number of places where the roofer has to stop and think. The variables are which slate is specified and whether it is new or salvaged, how much of the original covering can be re-used, the area and pitch, the number of valleys, hips, dormers, chimneys and abutments that need leadwork, the state of the battens and rafter feet once the roof is open, how the scaffold has to be built on the site you actually have, and whether heritage constraints dictate the detailing. On a terrace, access to the rear and the neighbours' agreement to a scaffold can matter as much as the roof.

What LokalMatch does is put the job in front of roofers, and nothing more than that. Describe the roof once with your postcode — its age, what is on it, what is happening to it, and whether the building is listed or in a conservation area — and slating contractors covering your area come back to you. Posting a request costs homeowners nothing, because the pros pay for the requests they receive. LokalMatch does not lay slate, does not set prices, and does not vet, rank or recommend anyone, so comparing the specifications rather than the totals is the part that stays with you.