Medium-rise building

10-storey Wendover flats facing Thurlow Street, Aylesbury Estate, Walworth, London cc-by-sa/2.0 - © Robin Stott - geograph.org.uk/p/5326176

[edit] Introduction

A medium-rise or mid-rise building is loosely defined as a structure that has between five and 10 storeys and is equipped with a lift. More specifically, the National Fire Chiefs Council classifies medium-rise buildings as ‘structures whose uppermost habitable floor is less than 30m and greater than 18m above ground level measured from the lowest side of the building’. This definition is based on the knowledge that standard firefighting turntables cannot be used to access the outside of buildings that are more than 18m high.

The National Fire Chiefs Council sets out addition requirements for medium-rise buildings higher than 18m and less than 30m:

• Compliance with Class 0 external surface requirements for the building envelope.
• Firefighting shafts with firefighting lifts.
• Increased time periods for structural fire resistance based on fire suppression systems within the building.

[edit] The 18m issue

This height specification for medium-rise buildings conflicts with that of the Home Quality Mark, which uses the 18m height specification to define high-rise buildings. This height has also been adopted by guidance following the publication of the Independent review of the building regulations and fire safety (also known as the Hackett Review) in 2018.

In December 2018, a Ministerial Working Group in Scotland made a change to its definition of a high-rise building with relationship to fire safety standards. This included a reduction in height from 18m to 11m. It did not include specifications for medium-rise buildings.

In January 2020, following a fire in a block of student accommodation (which was just under 18m) in Bolton in 2019, the government launched a consultation including proposals to lower the 18m height threshold for 'high-rise' to 11m.

[edit] The future of medium-rise buildings

There is no precise consensus as to what constitutes a high-rise building. This has had a cascading effect on definitions of both medium- and low-rise buildings. Low-rise buildings are sometimes referred to as those not tall enough to be classified as high-rise, which subverts the medium-rise classification.

Some industry experts speculate that fire and safety regulations may increase the preponderance of medium-rise buildings - or shorter high-rise towers. These buildings are sometimes referred to as groundscrapers, since they extend horizontally over a large distance while only being of a low to medium height.

[edit] Related articles on Designing Buildings Wiki

• Building height.
• Groundscraper.
• High-rise building.
• Low-rise building.
• Multi-storey structure.
• Storey.
• Tall building.