Terrace & Facade drainage Designing surface water runoff in urban environments

With building life expectancies increasing and permitted discharge rates being restricted, managing water from the roof to sewer can be a complex challenge. Careful consideration of attenuation requirements and hydraulic loads are needed to meet these challenges and select the correct and long-lasting drainage solution. 

Elevated and roof terraces, roof gardens, level thresholds and façades present specific challenges to specifiers and contractors. To tackle some of the symptoms of climate change, the reuse of rainwater and the requirement to make use of it at source are becoming increasingly important aspects of planning conditions imposed by local authorities. 

Terrace & Facade brochure

Terrace and Facade Brochure

An overview of specific water management solutions for terraces and facades

Drainage areas

Terrace and balcony thresholds

On a terrace or balcony, the primary aim is to remove the water from the surface as soon as possible enabling safe access and preventing water ingress into a building. These areas are often more exposed, receiving rainwater from the surface area plus other contributing areas, including run-down from the façade.

Raised or suspended deck structures

For a raised or suspended deck structure including permeable decking, open-sided drainage channels provide a path of least resistance to the discharge point, collecting water from both the surface and the sub-surface. 

Ground level threshold and Facade

Ground level façade and threshold drainage protects the exterior and ingress points of buildings, capturing rainwater runoff from the building itself and the surrounding area.Considerations include aesthetics for these public access points, heel safe options and adaptable linear, radial and bespoke designs to follow the building contours and curves.

Roof Gardens

Roof Gardens are green roofs, which can be partially or completely covered with vegetation and a growing medium, planted over a waterproofing membrane. They are an increasingly important part of sustainable urban developments, including sustainable urban drainage as they absorb rainfall and reduce flooding, whilst enhancing biodiversity and amenity for residents.

How can we assist you

Our Design Team

Collaboration is very much a part of ACO’s way of working. For over 50 years we have been offering creative design solutions to all sectors of government, public and private enterprise and have a track record for development and regeneration informed by community aspirations and environmental context. Our in house design team and our external design engineers have excellent technical understanding of interconnected systems that can help you create sustainable drainage solutions in all categories of the urban environment.

Tools to support you

We also offer software for design surface to assist you in making your own calculations, as well as design visualisers to assist in helping assess impact of various grating/inlet details. BIM product files along with a variety of other support documents are all available for download here.


Want to know more?

ACO offers a range of ways to enable you to continue your proffesional development with further knowledge on the range of drainage solutions around the Terrace + Facade. 

For more info on either our upcoming webinar, or to talk with us about arranging CPD training either In Company or at our ACO Academy in Shefford. Please send your contact details using the link below.