About
Architect: RSHP
Contractor: MACE
Sector: Education
Overview
Mossbourne Community Academy is a state-of-the-art education academy in Hackney. The school is a triangular layout with two long 3 storey wings catering for over 2000 students from the local community.
The Brief
Hackney Council in conjunction with the architect and main contractor commissioned Vision Ventilation to find a solution for extracting the hot air from the school during periods of high occupancy or high external temperatures whilst providing a means of preventing noise break-in from the adjacent railway line and back up mechanical ventilation during peak conditions.
Our Solution
8 No. Wind Towers which each nominally 4600mm x 4200mm square at the base tapering up to 2400mm x 2400mm at the top x 7500mm high and weigh more than 8 tons each were required to give the required extract ventilation performance. The ventilation system is located at roof level and provides extract ventilation to the whole of the building. The air moves out of the building via the roof mounted ventilation towers through the external louvre system around the perimeter. Low level inlet air is transferred through louvres in the low-level glazing provide clean air that is drawn through the classrooms up to roof level.
Fitted on the inside face of the louvers in the ventilation towers are intelligent dampers that are linked to the BMS and open and close as the system dictates. Fitted to the rear of the four weather louvres in each tower behind the dampers is an extract fan with a duty of 5m/s, these fans are linked to the BMS system and automatically cut in to provide boost ventilation in peak summer conditions to reduce internal temperatures within the building.
The solution was to design and install a series of roof mounted units to give the required extraction of hot stale air. To ensure the units performed to the required specification a full scale mock-up was produced in plywood but using the actual louvre / damper system to be incorporated into the installed unit to ensure this would give an accurate result.
The school is located close to a main railway line and therefore the units had to be designed to prevent noise break in so a large aerodynamic acoustic silencer pod was designed and fitted below the top section of the ventilation tower but still leaving enough free area to ensure the ventilation performance was maintained.
