Blue roof
A blue roof is a roof designed for the retention of rainwater above the waterproofing element of the roof. This is as opposed to more conventional roofs which allow for rainwater to drain from the roof. Blue roofs are typically flat, without any fall, with control devices regulate drainage outlets that enable water to be retained or drained.
The SuDS Manual published by CIRIA in 2015 suggests that a blue roof is: ‘A roof construction that stores water, can include open water surfaces, storage within or beneath a porous media or modular surface or below a raised decking surface or cover.’
Some of the reasons for incorporating a blue roof into a building, include:
- As a form of Sustainable Urban Drainage System (SuDS) to try and alleviate urban flooding caused by stormwater run-off.
- In areas of urban density, the space created by a blue roof can avoid having to provide attenuation for rainwater at ground level.
- Rainwater harvesting for use, independent from, or supplemental to the mains water supply, such as wc flushing or green roof irrigation
- Cooling solar panels, or reducing load on mechanical refrigeration or cooling equipment.
- For recreational purposes, such as rooftop swimming pools or water features.
Unlike some other forms of SuDS, blue roofs make use of spaces that might otherwise be redundant without extending beyond the footprint of the building or into ground space which, depending on the density of the location, may be expensive.
To ensure safety, there must be careful estimation of the flow restriction, which calculates the peak rates of run-off and the water depth that will be formed on the roof surface. This informs the design of the safety overflows, the preventative maintenance programme, and the design and construction of the waterproofing layer.
[edit] Related articles on Designing Buildings
- Blue infrastructure.
- Blue space.
- Brown roof.
- Cold roof.
- Condensation in buildings.
- Domestic roofs.
- Flat roof.
- Flat roof defects.
- Green roof.
- Groundwater control in urban areas.
- Interstitial condensation.
- Living Roofs and Walls, from policy to practice.
- Rain garden.
- Rainwater harvesting.
- Sustainable Urban Drainage Systems.
- Twickenham Studio - London's world-renowned film studio transformed.
- Warm roof.
Featured articles and news
Investors in People: CIOB achieves gold
Reflecting a commitment to employees and members.
Scratching beneath the surface; a guide to selection.
ECA 2024 Apprentice of the Year Award
Entries open for submission until May 31.
UK gov apprenticeship funding from April 2024
Brief summary the policy paper updated in March.
For the World Autism Awareness Month of April.
70+ experts appointed to public sector fire safety framework
The Fire Safety (FS2) Framework from LHC Procurement.
Project and programme management codes of practice
CIOB publications for built environment professionals.
The ECA Industry Awards 2024 now open !
Recognising the best in the electrotechnical industry.
Sustainable development concepts decade by decade.
The regenerative structural engineer
A call for design that will repair the natural world.
Buildings that mimic the restorative aspects found in nature.
CIAT publishes Principal Designer Competency Framework
For those considering applying for registration as a PD.
BSRIA Building Reg's guidance: The second staircase
An overview focusing on aspects which most affect the building services industry.
Design codes and pattern books
Harmonious proportions and golden sections.
Introducing or next Guest Editor Arun Baybars
Practising architect and design panel review member.
Quick summary by size, shape, test, material, use or bonding..