Too many construction projects fail to include fire safety management at the earliest planning stages. Yet when you do, you’ll save money, time and be more likely to save lives should fire break out.
Many building designers of big builds and refurbishments lack specific smoke ventilation expertise. Perhaps because it’s only required in buildings of particular size and use, smoke ventilation is often poorly designed or missed out altogether.
Sometimes these requirements are only considered after planning, when building regulations are consulted. By this point it’s difficult to integrate the most effective solution. This results is compromise and more expensive solutions. Is ‘compromise’ a description you ever want to hear about fire safety? Too little knowledge can backfire.
Where there is no specific smoke ventilation expertise, the responsibility gets passed on to fire engineers, who then have very little latitude to create a compliant building. Sometimes smoke vent specialists are only brought in late in design, or even once the building is under construction. This sort of timing is likely to end in more expensive and convoluted bespoke smoke vent design and manufacture.
As a rule, the more complex the building, the more in-depth the knowledge of regulations and British standards you need. Mixed or multi-use buildings may be particularly demanding. Combinations of shops, offices and living accommodation require a solution that addresses all the risks of high fuel loads, large open spaces and 24-hour occupancy. Likewise, many older buildings have severe restrictions on space for modern smoke control and their existing systems are likely to be non-compliant. In such situations, roofs, walls and floors often need to be altered and new fire-proof compartmentation installing.
Yet despite the inherent complications and specialist knowledge required in these more challenging buildings, an all-party meeting – on site and ahead of design – is rare. Perhaps it’s due to the time pressures of modern build programmes. Or perhaps it’s down to assumptions being made.
Things you need not to assume
Sometimes it’s the simple things that are most problematic, often arising from lack of smoke ventilation product knowledge. Examples include: when the angle of opening for smoke vents clashes with other structures; thinking that any control can interface with other building systems, such as BMS and door entry controls; and, most dangerous of all, that all equipment provided under the title of ‘smoke vent’ will be compliant.
It’s a matter of serious concern that there’s rarely a request for documentation or proof of certification. SHEV smoke vents are covered by a harmonised European Standard (hEN) and must be certified to BS EN12101-2). Receiving certification is surely the most fundamental of requirements, especially for a lifesaving device.
All too often, the smoke vent package is split into smaller parts and divided between the façade installation and M&E packages. Or it’s included within the electrical package. In the first situation – without extremely close coordination – the outcome can include ventilation and control compatibility issues, resulting in a non-compliant design. Handing over smoke ventilation to electrical subcontractors should only happen if they are smoke vent specialists. If they’re not, they’ll often have little or no knowledge of the basic requirements of smoke control. That can lead to frantic last-minute rectification and alteration to gain practical completion (PC) of the building. PC is an important date in the schedule and, while different schemes have different interpretations for PC, a working and commissioned smoke control system is non-negotiable.
Where a fire-engineered solution has been commissioned, smoke control, fire strategy documents and drawings tend to be accurate and clear. Without these, smoke control seems to take second place to other design requirements. A lack of joined-up thinking ensues, with inaccuracies around structural apertures, misaligned ducts and more. The inevitable result is reworking and alteration on-site. It’s a needless expense and additional time pressure.
Planning for a better, safer building
The reality is that there’s no ‘one size fits all’ template for a building. Nor is there for smoke control design. Building regulations may be open to interpretation and this can skew priorities. But when you assemble a team of specialists with mutual respect and bring them together before planning begins, you can easily sidestep the pitfalls.
What’s more, you’ll find additional benefits. A carefully designed NSHEV system, for instance, can add comfort cooling and daylight ingress. That means you’ll find it easier to comply with Approved Documents B and F with very little additional equipment and installation cost.
If a solution is designed at an early stage, adopted by the design team and detailed into all drawing issues, showing size, location, power requirements and interfaces, you stand to save hundreds of hours, thousands of pounds, and end up with a better designed, safer building.