Sacred Heart Primary School

Project:  Sacred Heart Primary School
Contractor: City Building Glasgow
Liquid waterproofing system: Hydrostop AH-25

SIG Design & Technology’s Hydrostop AH-25 product was chosen to refurbish 450m2 of roof at the Sacred Heart Primary School in the Bridgeton area of Glasgow. The project was specified by contractor City Building Glasgow, formerly the building service department of the local authority, as part of a wider refurbishment of the school premises. The school buildings date back to the 1950s. Areas of the roof had been leaking, leading to considerable water damage and disruption to some classrooms.

According to City Building Glasgow assistant investment manager Charlie McLean, the priority for the roof works was to procure a waterproofing system with minimal hot works that would cause as little disruption to the school’s everyday activities as possible. The chosen system would also need to be suitable for installation on a distinctively pyramidal part of the school roof. Another important factor was health and safety, both for those installing the product and the school community.

Sacred Heart Case Study Before website Image

Sacred Heart Case Study After website Image

Before and after photographs of the roof at Sacred Heart Primary School

City Building Glasgow chose the Hydrostop AH-25 system because it met these criteria and offered additional safety, health and time benefits. Hydrostop AH-25 is a wet-on-wet, cold applied liquid waterproofing product that is reinforced with a polyester fabric. It is free of solvents and hazardous materials, and has a very low VOC content, making it fume-free and virtually odourless. Installers like AH-25 because it goes down wet on wet in a single pass install and no additional respiratory PPE needs to be worn at installation.

AH-25 is totally impervious to standing water, and as it is a single component liquid, it does not require a catalyst to be mixed into the product before use. The product comes with 25-year guarantee for SIG’s accredited “DATAC” installers.

Sacred Heart Case Study Before Inset Image v2
‘Hydrostop could be installed with minimum personal protective equipment as it has no obvious smells or safety constraints,’ McLean says, adding that installation process was quick since it could be laid on a damp substrate by roller in a single application.

This meant the Hydrostop AH-25 system could be installed in just two weeks, with the whole waterproofing project, including the scaffolding, taking four to six weeks.

The Sacred Heart School project was the first time that City Building Glasgow had specified the Hydrostop AH- 25 system. In preparation for the installation, SIG set up a training facility at the City Building Skills Centre in Glasgow and ran a two-day training course for the contractor and subcontractor in the correct use of its product. City Building Glasgow expects to use the waterproofing system in further school refurbishment projects in the future.

SIG Design & Technology has recently added a range of warm roof systems using AH-25 to include Cut-To-Falls, flat board, recovery board for overlays and one for specialist acoustic applications. Fully tested, these warm roofs have achieved a fire rating of BROOF (t4).

Reproduced by kind permission of RIBA Journal

Sacred Heart Primary School case study

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