Case Study / Waterproofing
Luxury new build basement
Waterproofing a large basement with gym, pool and spa
MacLennan Waterproofing was engaged by contractor WG Carter to deliver a customized waterproofing solution for a large new build basement.
This single-storey basement, designed to accommodate a gym, pool, spa, massage room, yoga room, and showers, required an impeccable waterproofing system to ensure a leak-free environment.
Given the nature of the basement's intended use, it was crucial to achieve a Grade 3 waterproofing standard, suitable for habitable environments where no water ingress or dampness is acceptable. This high standard was necessary to meet the stringent requirements of NHBC, GPI, Premier Guarantee, and BLP.
BS8102:2022 emphasises the importance of employing a combined protection strategy when designing waterproofing systems for below-ground structures. This means that, to ensure maximum effectiveness and reliability, it is recommended to use at least two different forms of waterproofing.
Method
The project began with a thorough assessment of the site to identify potential water ingress points. Based on this assessment, a tailored waterproofing design was developed, incorporating both external and internal waterproofing measures to ensure maximum effectiveness.
To enhance the waterproofing capabilities of the structure, the internal surfaces of the reinforced concrete were treated with a crystalline coating. This treatment helps to block water pathways within the concrete, providing an additional layer of protection.
A ventilated cavity drain membrane system was installed from floor to ceiling, serving as the primary waterproofing measure. This system included a Hydrodrain channel around the wall-floor junction and wall-mounted inspection ports to ensure full serviceability. The cavity drain system effectively manages any water that might penetrate the external barrier, directing it to a sump pump for removal.
Sumps and pumps were installed to manage and remove any potential water ingress, providing an additional layer of protection. These components are crucial for maintaining a dry environment, especially in areas with high water tables or frequent rainfall.
Special attention was given to sealing service entry points, which are common failure points in waterproofing systems. Suitable sleeves were installed through the retaining walls, secured with concrete, and equipped with hydrophilic strips or puddle flanges to prevent water ingress. Gaskets were used to seal the entries, ensuring a watertight fit and accommodating any movement due to soil settlement or structural shifts.
As the works were carried out during the winter months, a marquee-style shelter was erected over the site to keep it dry. This shelter allowed the MacLennan technicians to complete the installations without disruption, ensuring that the waterproofing materials were applied under optimal conditions.
Result
The project was completed successfully, with the basement achieving the required Grade 3 waterproofing standard.
The combination of external and internal waterproofing measures, along with the meticulous sealing of service entry points, provided a robust solution, ensuring a dry and habitable environment for the gym, pool, spa, massage room, yoga room, and showers.
All works were completed within the time frame and budget, offering our insured products guarantee.
3d Details
