Case study: July 2023
SSQ Riverstone Ultra slates
Wrap around, lean-to extension. Coastal region, Weymouth, Dorset.
Built 10 years ago, in order to overcome an issue with a side entrance door, the construction of this roof was modified which subsequently resulted in the roof being pitched at 10 degrees rather than the 15 degrees specified. A low pitch interlocking slate system was installed in the open rafter application with a breather membrane.
The roof began leaking through the celling below. Unable to contact the original builder, the customer consulted roofing contractors, who explained that the roof pitch was far too low and the cost to replace the roof incorporating a flat roof waterproofing system would be considerable.
Unable to afford the replacement roof, and determined to retain the slate roof appearance,
the customer attempted many repairs using flash band to restrict the leaks and even painted the interlocking slates.
Figure 1 – 4 - The existing leaking roof
The customer investigated slate application for low pitches and realised natural slate could not be used on their project. Upon discovering the high performance ArmouredSlate system, he contacted Mayan.
ArmouredSlate is a roofing system that allows natural slates to be installed at a low pitch, in the single lap method. The patented technology was tested at the BRE with outstanding performance results down to 10 degrees with no leaks. As well as the outstanding weatherproofing performance, the ground-breaking system has a traditional appearance, is fire-rated and easy to install.
The customer wanted a premium slate roof appearance. He also required periodic access to the roof to maintain the solar panels. Part B of the new fire safety act also applied due to the proximity to the neighbour.
The solution to this roof was the ArmouredSlate system with the correct use of detailed installation procedures in combination with several of Mayan’s other unique, high-performance slate roofing products.
SSQ 320 x 220 Riverstone Ultra slates were chosen because of their excellent appearance, strength and durability.
ArmouredSlate can be installed using either 80mm slate hooks, or our special SlateFix screws. However, 100mm slate hooks were chosen for an increased head lap, to provide a further defence due to the very low pitch and added ease of maintenance.
Because of the low pitch, the eaves tray (EPS) was set below a 25mm over fascia vent to allow condensation on the breather membrane to drain fully into the guttering.
ArmouredSlate allows for an adjustable batten gauge. The batten gauge was set at 222mm to neatly fit the courses into the main building.
Figure 2 - Batten Gauge
RealVerge was chosen for the verge. RealVerge is a natural slate, dry fix verge system with an excellent appearance. The combination of the ArmouredSlate system and compatible handed left and right RealVerge units are perfect for a lean-to application.
Figure 3 - Mayan RealVerge
The ArmouredSlate lengths hook over the top of the battens and the slates are then fixed directly on top in the single lap method. The lengths are extended across the roof and the pre-installed weld-tape seals the lap when the protective paper is removed.
Figure 4 - Mayan ArmouredSlate Installation
|To form a permanent waterproof seal below the hip ridge, the ArmouredSlate was simply mitred and sealed using a chevron of self-adhesive ArmouredFlashing.||
Figure 5 - Example of ArmouredSlate installation at the hip
It was not possible to extend the apron flashing at the top course, therefore the self-adhesive ArmouredlFlashing was applied onto the wall down to the ArmouredSlate and under the slates with the existing lead then on top. This formed a permanent watertight seal against the main building whilst maintaining the required appearance.
Figure 6 - Apron Flashing
Mayan manufactured a precisely measured, bespoke hip starter unit to be used with the bestselling All-in-One slate ridge tile system. The highly practical and waterproof solution looks fantastic when entering the house.
Figure 7 - Bespoke Dutch Hip starter
Figure 8 - Bespoke natural slate dutch hip starter
Figure 8 - All-in-one Natural slate RealRidge - 135°
The customer was extremely pleased with the outstanding appearance of the finished roof, the speed of installation and the overall competitive price of the Mayan ArmouredSlate roofing system with the highest quality slates.
The weekend immediately following the installation, extreme, “tropical style” heavy rain fell. The customer telephoned the office explaining that he nervously monitored the roof. For the first time in 10 years he had “no leaks whatsoever!”.