BS EN 12056-3: Rainwater Drainage Design
BS EN 12056-3 is particularly important as it’s the approved method for calculating guttering and downpipe sizes. The standard lists rainfall intensity, effective roof area, gutter capacity, and outlet capacity as key considerations.
Specifically, it suggests that the sourcing of local rainfall intensity information is crucial for selecting the correct rainwater outlets and guttering. This figure is then multiplied by the total area of the roof in question to provide the total run off that must be accommodated by the rainwater system.
To help architects and contractors fully comply with BS EN 12056-3, we have produced two online calculators which provide step-by-step guidance to fast and simple roof drainage design. When complete, a full set of calculations are produced that confirms product suitability.
BS 9101:2017: Steel and Aluminium rainwater systems
BS 9101:2017 is the regulation for the design and manufacture of metal gutters for a range of building types, particularly for commercial and domestic buildings.
This standard covers materials, tolerances, mechanical properties, surface conditions, coatings, jointing methods and fixings for rainwater systems. It also informs architects and contractors of the available specification options and provides robust criteria that a gutter must meet to be classed as functional.
The standard covers most metal gutters with some exceptions and is more comprehensive and detailed to meet specific metal sheet and extruded gutter requirements. It also emphasises the design strength of the metal gutter, which is determined by loading capabilities in the form of water loading, wind uplift, and snow loads.
BS 8530:2010: Traditional-style aluminium rainwater systems
BS 8530:2010 covers UK styles of traditional cast and extruded aluminium gutters and fittings together with extruded aluminium rainwater pipes with cast aluminium sockets and fittings. As such, it represents all Traditional-Style Half Round, Beaded Half Round, Victorian Ogee and Moulded Ogee rainwater systems made from aluminium, providing an authentic replacement for traditional cast iron systems on heritage buildings.
Marley Alutec’s Traditional range products are available in a choice of designs, such as Half Round, Moulded and Victorian Ogee and also a range of colours including Heritage black, which mimics the textured appearance of traditional cast iron.