26 August 2020

DRY RISER RULES AND REGULATIONS

We often get asked various questions by our clients who are unsure about the rules and regulations when it comes to installing dry riser systems correctly. Although dry risers are simple, there are a few key requirements that need to be taken in to account when designing and installing these systems. All buildings that require dry risers will need to be signed off by building control to ensure that it is fit for purpose and installed to current British Standards.

CABINET HEIGHTS

All dry riser cabinet heights should fall between 400mm and 600mm from finished floor levels to the bottom of the cabinets. If your building design doesn’t allow for these heights certain allowances are made, this will have to be agreed with your local authority. Cabinets are not always required and there nothing in the standards that say that landing valves can’t be free standing, secured with strap and padlock.

LANDING VALVES

Dry Riser Landing valves are required on each floor of a building, and each valve should be no more than 45 metres apart. The heights of these valves should be 800mm off finished floor. We always advise our clients to install male threaded valves where possible for ease off maintenance.

INLET VALVES

Dry Riser Inlet valves should always be in a prominent position and no more than 18 metres from fire brigade access point. Ideally these valves should be in a cabinet, either recessed or surface mounted. The colour and locks of this valves can vary as long as there sufficient signage.

DRY RISER PIPE SIZE

Dry riser pipework comes in two different sizes 4 inch and 6 inch. Most dry risers are installed in 4 inch galvanised steel pipework and this is generally sufficient. Six inch is only used if you have more than one landing valve per floor or your building height requires a larger volume of water on the higher floors. All dry riser systems have a automatic air release valve at the highest point this allows air to escape but seals the water once the pressure builds.

Dry risers need to be regularly inspected to ensure the fire protection is in good working order in the unlikely event of a fire. British standards dictate that you have a 6 monthly visual inspection carried out. And a more in depth hydraulic pressure test annually.