Fire Boundary Requirements For Steel Buildings & What They Will Look Like
When we are contacted about the design of a steel building, we aim to give a realistic indication of what the project will involve, and that can include anticipating additional demands likely to be made by building control. These can include things such as alterations to emergency access routes, additional personnel access doors, or additional works required to provide a fire boundary.
Building regulations stipulate that there should be a minimum amount of space separating buildings and that the external walls offer resistance to the spread of fire from one building to another. External wall supports must also be fire-protected and any cladding used must be fire-resistant.
Requirements vary depending on the individual building and the site it occupies. You might think that if your building sits in a field, for example, with no other buildings nearby that a fire boundary isn't something you'd need to take into account, but you could be wrong – it's important to understanding the requirements early on. The size, height and internal construction layout of your building can also have a bearing on requirements, and if the distance between it and any other building(s) is less than one metre, requirements are even more stringent.
How To Design A Steel Building Fire Boundary Wall
As a general rule, most external walls that are adjacent to a boundary property are expected to provide a minimum of sixty minutes resistance to fire. (The other walls of the building do not need to provide this, but consideration has to be given to what might happen if they were to collapse in a fire.) The use of sprinklers can make a difference to the boundary requirements, but the additional cost and load have to be factored in to the overall project budget and design.
Creating a fire boundary can involve different processes depending on whether your building is constructed using cold- or hot-rolled steel. Fire boundaries for cold-rolled steel buildings require special moment-resisting base plates that are heavier duty and made of hot-rolled steel. They will also need to incorporate a composite panel with a suitable fire rating, and the columns must be insulated with a fire-rated plasterboard.
In the case of a hot-rolled building a fire rated composite cladding is again required, and the columns adjacent to the boundary must be coated in an intumescent paint. This is a thick substance that is applied to the main structural steel columns and which reacts to heat. As the temperature rises the coating swells and forms a layer of char, protecting the steelwork.
Help With Fire Boundary & Steel Building Design
If you are considering a steel building and want to discuss your options, taking into account any additional requirements that may be involved, get in touch. We have the knowledge and experience to anticipate requirements that may be imposed by building control.
Tackling building regulation requirements in the early design phase of your project will help to avoid any big changes or re-designs further down the line. Get in touch with us today to begin your steel building design or to help you review designs for building regulations.