Introduction
In this residential development, steps provide access to the property frontages. The precast concrete stair units were originally waterproofed with a thin layer of waterproofing furnished with terracotta tiles as overburden.
The challenge
Water ingress was evident between the pre-cast concrete stair units and the brick upstands at the sides of the stairs. The existing waterproofing was only apparent on the step structure, and not on the upstands. This was deemed to be poor and concerns were raised about the waterproofing durability for the areas that were waterproofed.
Action was required to ensure the stair structure was watertight for long term structural protection.
In addition, water was ponding on the external landings and some of the steps presenting a slip risk.
The solution
Following a Triflex site survey, a bespoke project specification was provided to Thorntons Chartered Building and Valuation Surveyors.
Triflex StairCoat Reinforced with Quartz was proposed for the 20 sets of steps and landings complimented by Triflex ProDetail for the upstands.
For the preparation, the tiles were removed from the steps, and where present, any remnants of the existing waterproofing was removed by grinding. To address the issue of ponding water, Triflex ProFloor mortar was applied to the landing areas and some steps to create a fall across the depth of each step. The PMMA based system is specifically designed to act as a horizonal repair and leveling mortar for walkway, balcony and terrace systems. Whilst PMMA is hydrolysis resistant and will not degrade in ponding water, a repair was required for the safety of residents.
Triflex ProDetail is a certified reinforced cold liquid applied waterproofing membrane. It allows details to be waterproofed seamlessly and quickly. Here it was used for the upstands, providing a self terminating solution ensuring the continuity of waterproofing between the stairs and brick upstands. The Triflex StairCoat was then applied to the stairs and landing providing a reinforced, dynamic crack bridging solution that will protect the structure from the elements. The quartz finish provides an anti-skid surface, with a practical grey colourway chosen from the 50 UV stable colours available. The PMMA based systems are rainproof in just 30 minutes and cure in as little as 45 minutes. Thanks to the ultra-rapidly curing PMMA Triflex, disruption to residents was minimalised.
The stairs and landings are now waterproofed and protected with even surfaces and a pleasing aesthetic. The installation was carried out to a high standard by Triflex Authorised Contractor May & Family Roofing.
