automated design.
Ideally, new riser space can be formed in such a way that it doesn’t significantly reduce net usable lab space or cause issues with adjacent tenancies (where relevant).Where this isn’t possible, external ductwork can be considered, however there are other issues such as building appearance and Planning Permission that can make this unfeasible.. Exhausts for fume cabinets, ducted MBSCs, storage cabinets, and LEV (local extract ventilation) will also need to find their way to roof level.
With limited riser space this means upper-floor office conversions are preferable, though these tend to be less advantageous from an access or structural point of view..It is essential roof exhausts have efflux arrangements that ensure discharged fumes get sufficiently away from the building to prevent recirculation into make-up systems or to anyone on the roof or in a nearby building.In the UK, the British Standard has a blanket statement requiring fume stacks be either 3m high or 25% the building height – whichever is greater.
For tall buildings this can lead to very high stacks that would impact the building’s appearance and will likely require Planning Permission.For example, a 10-storey office building with an average floor to floor height of 4m would require a stack 10m tall (nearly 3 storeys.)
There are a few ways to challenge this, including CFD (Computational Fluid Dynamics) modelling and the use of alternative discharge stacks (e.g.
strobic fans), which may be necessary for some office to lab conversions.Individual spaces e.g.
a patient room, which has certain needs, regulations.Group of spaces e.g.
complex departments such as operating theatres, where all aspects of the room are dependent on each other to work properly.Whole asset e.g.