Interlocking Slates KEY QUESTIONS REGARDING INTERLOCKING SLATES Tom Woodhouse, Site Services Manager at Marley, answers contractor questions about interlocking slates. Since the recovery in the housing market and escalating skills and time pressures, there has been a huge surge in demand for interlocking concrete slates. Offering a middle ground between the top and bottom of the roofing price range, thin leading edge, interlocking concrete slates are a quick and affordable way to create a stunning slate effect roof. They can be used for both new and refurbishment projects and, unlike traditional slates, they don’t require specialist skills and can be installed by any roofer. If you’re thinking about upgrading your concrete tiles to give your roofing project a premium finish, below we answer some frequently asked questions about interlocking slates… 1: How much do they cost? As a cost-effective alternative to both natural and fibre cement slates, interlocking concrete slates are the most economical way of achieving a slate aesthetic. While they are a bit more expensive than a standard flat interlocking concrete tile, it is a relatively small difference in cost. For a premium look interlocking concrete slate, like our Edgemere product, the difference can be as little as 3% extra on the total cost of a standard domestic roof. The average cost of a reroof is around £3,500, so you are only paying just over £100 to upgrade from a standard tile to a premium look slate. 2: What min pitch can they be used at? The minimum pitch will vary according to which type of interlocking slate you buy, but usually they can be used at a lower pitch than natural slate. Above: Marley offers the Edgemere interlocking concrete slate. For example, our Edgemere slates can be used down to a low minimum pitch of 17.5 degrees. 3: Will the tiles be accepted by planning as a natural slate replacement? This will depend on what type of interlocking slate you are using and where you are installing it. In many cases our Riven Edgemere slate, which is designed to more closely resemble a natural slate, is accepted by planning departments. However, you will need to check with the local planning office as it will depend on the proposed location. There is also a new Anthracite colour in our Edgemere range, which is designed to provide a closer aesthetic match to both natural and fibre cement slate. This gives you a cost-effective easy-to-fix option when a slate appearance is required by planning. 4: I’ve been told fibre cement slates are too light, so can I use concrete slates to replace a natural slate roof? When changing a roofing material for one that is lighter or heavier, we always recommend consulting a structural engineer to give you appropriate advice on load bearing. It is true that on some refurbishment projects, fibre cement slates may be unsuitable to replace an existing natural slate roof. However, at around 44kg/m², our Edgemere concrete slates are not that different in weight to a natural slate, so they could be a suitable replacement but it would depend on the structure of the building and planning conditions. 5: What is the coverage rate? Interlocking slates are designed to be very quick and easy to install, with a high coverage rate – ours is 9.7 tiles per square metre. Like all interlocking tiles, they should be fixed to BS 5534 recommendations, both for new build and refurbishment projects. 6: How can I install them to BS 5534 more quickly? Since BS 5534 was revised in 2014, all interlocking tiles are subject to more stringent fixing specifications, which means there is an element of clipping on all roofs laid in single lap tiles. Traditionally, these clips and nails come in separate bags and need threading together prior to installation, which is fiddly and adds extra labour time to the job. To save time, you can use the SoloFix one-piece clip and nail. It’s comparable in price to a standard aluminium clip but can save as much as 30% on roof clipping time. Contact Marley 01283 722 588 www.marley.co.uk/Edgemere @MarleyLtd 30 TC JANUARY <strong>2019</strong>
octor the A Proctor Group Collection <strong>2019</strong> the authority design by: Sarah McClintock Roofshield air permeable vapour permeable roofing underlay 01250 872 261 Proctor Group www.proctorgroup.com