Ambar Kelly

Principal Designers

Riser shafts are an intricate part of every multi-storey building in the world. These shafts house the vertically rooted mechanical electrical and plumbing (MEP) services that are required to feed the building with the resources on every level during its operation.

Holistic focus

These riser shafts start their lives as holes in a floor slab structure that are usually positioned one over the top of each other. The primary concern at this point is to protect the construction workforce from the risk of working at height and falling through these openings. But what happens is that these riser shafts, as construction continues, touch every part of the process from the foundations to a roof. The essential element that must be designed into these shafts is the maintenance flooring, which provides safe fire resistant (because of the chimney effect of the shafts) flooring for the MEP service engineers and others to access with complete safety throughout the building’s life.


The value of looking at these riser shafts early in the design process at RIBA (concept design) stage 2 is intrinsic to the successful construction and use during the building’s lifecycle. The key things to consider are not only the visible risk of falling from height through these riser openings, but where these shafts are located and the impact they have on the intended use of the building.

How are you going to design out risk during construction to meet the five standards associated? E.g. CDM 2015, HSG 168, Fire prevention on construction sites, Approved Document B and working at height regulations 2005. A potential solution would be to translate design into efficient and cost controlled construction without delays, through adopting an early design approach. Another may be accommodating the trade-off between size and location, fire protection, (horizontal as well as vertical), access to monitor and maintain those services throughout the buildings life and provide adaptable solution for the future.