Prepare for a rainy day with Glidevale Protect’s cavity trays

Cavity trays are a purpose designed product, developed to prevent water penetration that has seeped through the porous outer façade of the building. By redirecting the water back out of the cavity wall and away from the inner wall leaf via the use of weep holes within the trays, they help to limit damp from impacting on the structure or internal finishes. To support the housebuilder or bricklayer on product selection, Glidevale Protect offers comprehensive technical support services, including design take-off and guidance at the early stages to on-site toolbox talks for installation guidance.

Glidevale Protect’s extensive range of cavity trays are ideally suited for use in brick, block or random stone external masonry walls. As well as being necessary in double leaf masonry construction, cavity trays are required for masonry cladding to timber frame construction. Highly robust with a universal design, they have a variety of features to ensure ease of installation and compliance with the relevant Building Regulations, NHBC Standards and BS code requirements. These include integral weepholes for active drainage, integral roof pitch markings for quicker installation and more accurate positioning, as well as self-supporting upstands enabling the trays to be used with cavities of any width from 50mm upwards, avoiding the need for the tray to be built into the internal masonry wall and eliminating cold bridging.

The latest NHBC standards 2025 state that when cavity trays are being used to ensure damp proofing in external masonry walls at complicated junctions such as where the pitched roof abuts at an angle with the wall, preformed stepped cavity trays should always be installed. These stepped trays should have two stop ends at the lowest cavity tray and a weep hole to allow water to drain from the cavity. The standards also rule out the use of cavity trays manufactured from low density polyethylene (LDPE). Glidevale Protect’s cavity trays meet these requirements as they’re preformed, are manufactured from polypropylene and incorporate integral bed weeps.

Glidevale Protect’s cavity trays also have a unique ‘flexi-mouth’ mortar barrier on the lower leading edge of the tray with pull out protruding tab. Once the mortar has set, the tab is pulled and the hinge breaks away leaving a 25mm deep groove which allows the contractor to insert a cover flashing without the need to rake out the joint, which could damage the tray. This feature ensures that the tray maintains its integrity against water penetration at this otherwise vulnerable point.

Abutment and horizontal trays are available with optional factory-fitted flashings, which are pre-shaped and securely attached to the trays, for quicker and more reliable installation. The trays also have an integral ribbing or textured finish which provides an excellent mortar key. To simplify detailing and installation onsite, Glidevale Protect also offers a range of pre-formed accessories such as internal and external corners and stop ends.

Glidevale Protect’s Technical team can provide a comprehensive technical advisory service covering product advice and selection, estimating, and DPC design to meet all regulatory requirements as well as a site take off service and plot-by-plot delivery. The team has also recently joined forces with the NHBC to deliver insightful training at NHBC Training Hubs in the UK, with demo sessions focused on cavity tray installation. Contact us on +44 (0) 161 905 5700 or email info@glidevaleprotect.com for more details.

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