Rain gutter
The word 'gutter' originates from the Latin 'gutta' meaning 'a drop' which developed to mean a groove cut into something, or a furrow made by running water.
A rain gutter, also known simply as a gutter or guttering, is part of a building’s water discharge system. It is a trough or channel that runs around the perimeter of a roof, and collects rainwater runoff from the roof, discharging it, usually to rainwater downpipes which convey it to a drainage system. This protects the exterior surfaces of the building and its foundations from damp and potentially suffering damage.
The Building Regulation’s Part H, Drainage and water disposal, requires that adequate provision is made for rainwater to be carried from the roof of buildings. Approved document H suggests that to achieve this, roofs should be designed with a suitable fall towards either a surface water collection channel or gutter that surface water to vertical rainwater downpipes, which in turn connect the discharge to the drainage system.
The size of guttering can be determined from the area of the roof (metres) and the anticipated rainfall intensity (litres/sec/sq. m - the amount of water likely in a 2-minute rainstorm). There are a number of calculators that can be used to size gutters and rainwater downpipes based on this information.
Commonly used gutter designs include:
- Box gutters: These are rectangular and ‘boxed’ into the roof so as not to be visible.
- Fascia (or eaves) gutters: The gutter and fascia are combined so that the gutter appears to be build in to the eaves.
- Square gutters: Typically fixed to the outside face of the fascia, square-shaped and preferable in areas of heavy rainfall.
- Round gutters: Typically fixed to the outside face of the fascia, and half-circle-shaped.
- Quad (or ‘D’) gutters: Typically fixed to the outside face of the fascia, they are available in a range of different widths and profiles.
Traditionally, guttering was made out of lead, which was largely replaced from the late-18th century on by cast iron. This enabled gutters to be mass produced. Conservation projects will still specify cast iron gutters for restoration but these can also be replaced with cast aluminium.
Domestic guttering is typically made from uPVC sections, which are easily installed, cost-efficient and lightweight. They require minimal maintenance, apart from ensuring they do not become blocked, and have a good life expectancy. Standard components are available to allow them to be fixed, as well as corner section, connections for downpipes, and so on.
Gutters may also be made from materials such as aluminium alloy, galvanised steel, stainless steel, copper, zinc, and so on.
[edit] Related articles on Designing Buildings
- All eyes up to plastic rainwater systems.
- Approved Document H.
- Correct way to fix lead guttering.
- Difference between drains and sewers.
- Drainage.
- Drains.
- Fascia.
- Groundwater control in urban areas.
- Rainwater.
- Rainwater downpipe.
- Rainwater goods.
- Rainwater harvesting.
- Rainwater head.
- Rhone.
- Roofing defects.
- Sanitary pipework.
- Secret gutter.
- Sewer construction.
- Soakaway.
- Soil vent pipe.
Featured articles and news
Shading for housing, a design guide
A look back at embedding a new culture of shading.
The Architectural Technology Awards
The AT Awards 2025 are open for entries!
ECA Blueprint for Electrification
The 'mosaic of interconnected challenges' and how to deliver the UK’s Transition to Clean Power.
Grenfell Tower Principal Contractor Award notice
Tower repair and maintenance contractor announced as demolition contractor.
Passivhaus social homes benefit from heat pump service
Sixteen new homes designed and built to achieve Passivhaus constructed in Dumfries & Galloway.
CABE Publishes Results of 2025 Building Control Survey
Concern over lack of understanding of how roles have changed since the introduction of the BSA 2022.
British Architectural Sculpture 1851-1951
A rich heritage of decorative and figurative sculpture. Book review.
A programme to tackle the lack of diversity.
Independent Building Control review panel
Five members of the newly established, Grenfell Tower Inquiry recommended, panel appointed.
Welsh Recharging Electrical Skills Charter progresses
ECA progressing on the ‘asks’ of the Recharging Electrical Skills Charter at the Senedd in Wales.
A brief history from 1890s to 2020s.
CIOB and CORBON combine forces
To elevate professional standards in Nigeria’s construction industry.
Amendment to the GB Energy Bill welcomed by ECA
Move prevents nationally-owned energy company from investing in solar panels produced by modern slavery.
Gregor Harvie argues that AI is state-sanctioned theft of IP.
Experimental AI housing target help for councils
Experimental AI could help councils meet housing targets by digitising records.
BSRIA Occupant Wellbeing survey BOW
Occupant satisfaction and wellbeing tool inc. physical environment, indoor facilities, functionality and accessibility.