There are a number of aspects to consider when designing an office mezzanine floor, from building control considerations, through to your power, data and lighting requirements. It’s a lot to take in, so that’s why we’ve put together a guide to help ensure you receive an office mezzanine floor solution that makes the most of your available space and adheres to all regulations.
Mezzanine floors can be designed to accommodate office space on top, allowing companies to house their office space in the air and in turn freeing up valuable floor space for production, manufacturing or storage space.
When designing a mezzanine floor for office space it’s important the mezzanine floor is designed with the correct loadings. Typically a mezzanine floor that is to be used to accommodate office space will be designed with a 3.6kn/m2 capability which means that the floor would be capable of accommodating 360kg every square metre.
It’s also important to get the deflection of the floor right. Unlike a storage mezzanine floor which has quite a lot of deflection, the office mezzanine floor needs to be rigid. This is to ensure the floor isn’t ‘bouncy’ which would crack plasterboards and be noisy when walking around. When designing a mezzanine floor for offices the floor should be designed with a deflection of L/360.
Mezzanine floors are very flexible and can be designed to accommodate office space below as well as above. A good mezzanine floor designer will be able to hide the mezzanine floor columns within the desired office layout, making sure columns are located in the corners of rooms or hidden next to building columns.
If designed correctly a mezzanine floor will be inconspicuous and it would be difficult to know a mezzanine was the support structure for the office space. Mezzanine floors are typically designed around reception areas, WC areas, Meeting room, office space and canteen or locker facilities on the ground floor.
When designing a mezzanine floor to house office space, it is important it’s designed to conform to building regulations. Firstly the structure must be designed to be one hour fire rated.
This is achieved by installing column cases to the mezzanine floor (or cladding them in plasterboard), installing fire rated fascia to the exposed edges of the mezzanine floor and installing a suspended ceiling to the underside of the structure.
These three components ensure that in the event of a fire, the structure will stand for a minimum of one hour to allow all staff members to vacate the building in a safe manner.
Other considerations of building control are location and the number of staircases required. A mezzanine floor should be designed to keep the travel distances from any point on the floor to an exit to a minimum, allowing quick escape in the event of emergency.
If the mezzanine floor is small in footprint, often one unprotected staircase is sufficient. However on large floors, two staircases are often required, with the main staircase enclosed within a 60 minute fire rated enclosure. This enclosure is manufactured from a plasterboard system.
The mezzanine floor and office space in comparison to the size of the warehouse will determine if the partitioning dividing the office space and the warehouse needs to be fire rated.
Generally if the office space occupies more than 20% of the overall footprint of the building, the dividing wall will need to be fire rated to one hour. This includes any fixtures and fittings within the wall such as doors, windows or glass partitioning modules.
The offices that are located below or above the mezzanine floor will need to be designed with the correct lighting. The minimum lux level required for a person who uses a computer is 400 lux so its important this criteria is met.
Lighting on the ground floor will also need to be fire rated to one hour to maintain the fire integrity of the floor. Modern LED fittings are generally fire rated to one hour as standard, however if the fitting is not fire rated, it will need to be fitted with a fire hood which keeps the one hour barrier intact.
Smoke detection on the office mezzanine floor is also required. Each room or area underneath (and above) the mezzanine floor will require a smoke detector. This is so in case of a fire in any room it would sound the fire alarm which will instruct people to leave the building.
The smoke detection to a mezzanine floor can easily be added to an existing fire alarm system, or if the project is a new build, it will be specified as a new system from the offset.
Mezzanine floors are perfect for housing power and electrical requirements for your office space. Floor boxes can be incorporated into the design of the mezzanine floors, which in turn offers lots of flexibility when positioning desks and furniture on the mezzanine. The floor boxes house all the power and data requirements, allowing desks to be positioned anywhere on the mezzanine floor.
There are a range of partitioning systems that can be utilised when designing a mezzanine floor for office use. Typically a stud and track partitioning system will be used to construct the required rooms below or above the mezzanine floor.
The plasterboard systems are available with a range of performance characteristics. Different plasterboard system offer varying fire and sound performance which should be considered throughout the design stage of a mezzanine floor solution.
Sound performance plasterboards should be utilised in meeting rooms, WC and private office areas to ensure conversations or sound is not transferred between the areas. Fire rated boards are used to create fire corridors, staircase enclosures or dividing walls. Plasterboard as standard is fire rated to 30 minutes, however generally fire protection to one hour will be required.
Other partitioning systems can be used to compliment the stud and track partitioning system. Glass partitioning is a common system integrated into the design which can be used to create an open plan feel or create a sense of prestige when incorporated into meeting room and office spaces.
If the mezzanine floor is to be situated in a warehouse, a standard steel staircase may be sufficient. Generally painted black with contrasting nosing’s, these staircases are practical and economical.
If the staircase is to be used in a more prestigious environment, a higher grade staircase could be specified, potentially manufactured using stainless steel balustrade incorporating steel wires or glass.
Generally office staircases are designed 1200mm wide, with a dimension on the tread of a minimum of 250mm and a rise of 170mm. The staircases also have a landing after 12 (sometimes 16) treads. The staircases are designed this way to be wide enough for people to pass on the stairs and the landings act as resting point.
During the design stage it will be determined if the mezzanine floor requires a lift. If the office space is exclusive to the first floor and there is no capacity to accommodate a disabled employee or visitor, then a lift will be required (This is applicable to large scale mezzanine floors and not relevant to small mezzanine floors with offices).
Ideally the mezzanine floor will be designed so there is office space on the ground floor alongside WC, Meeting and kitchen facilities. Essentially if there any exclusive work areas on the mezzanine that aren’t on the ground floor that a wheelchair user can not access, you will require a lift.
If a lift is required for the project there are different options available. Typically a platform or scissor lift is the most cost effective solution or a more traditional lift can be installed that will carry multiple people and would require a pit.
For any project that involves a mezzanine floor and multiple trades, it is a requirement that the client appoints a principal designer for the project. This is to ensure that throughout the design stage all considerations regarding health and safety from a construction perspective are considered and also takes into account how the finished project will be accessible from a maintenance perspective.
The client would formally appoint their principal designer who would design the scheme from the outset. More information regarding the clients obligations with relation to a principal designer can be found here: http://www.hse.gov.uk/construction/cdm/2015/principal-designers.htm
Prior to commencing any project that involves multiple trades on site, the client must appoint a principal contractor. The principal contractor is responsible for all sub-contractors working on the project and encompasses them into the overall project plan.
Even if the client intends to use their own specific sub contractors for elements of the project they must fall under the umbrella of the principal contractor. The principal contractor is responsible for all health and safety aspects of the project and the overall programme of works.
More information regarding the role of a principal contractor can be found here. http://www.hse.gov.uk/construction/cdm/2015/principal-contractors.htm
If you would like assistance implementing a mezzanine floor based solution into your business, we would be delighted to design a bespoke solution for your needs. We will expertly guide you through the whole process of designing and implementing a mezzanine floor solution into your business.