Following on from our previous post describing the Ideas Stage, once we have agreed on an idea, we then work on detailed designs and calculations to bring your solution to life.
Approach
Every building design is different so no one ventilation product works in all applications. Often an off the shelf product does not work effectively unless the building is changed to suit that product. At Vision we have a different approach; we design the product to suit the building and design the natural ventilation strategy to optimise the building and its location.
In general, we start with a natural ventilation design that generally fall into three specific categories:
Louvres, Grilles and Dampers
The simplest and most cost-effective way to naturally ventilate a space is to install low level ventilation to allow fresh air into the building. As the air moves through the space it gradually warms trapping contaminates as it flows. The warm air is more buoyant than the incoming air so naturally rises drawing in new replacement air flow controlled by volume control dampers positioned behind the louvres. To assist the ventilation air change rate the warm passive stack rises to high level and is allowed to exhaust through high level louvres or windows.
Windcatchers
Roof mounted louvred turrets fitted with internal quadrant splitter plates. These are designed to harness the prevailing cool dense wind and are ideal where the building is in a highly polluted areas where low level inlet only introduces additional contaminates. Both inlet and extract air are transferred throughout the building using fresh air from the roof area.
As the wind blows cool air enters the turrets and into the building, the flow is uninterrupted as its segregated by the internal splitter plates. At the same time on the leeward side warm contaminated air rises as a passive stack that is exhausted through the turret assisted by a negative draw created as the wind passes over the turret. The process constantly self regulates under all weather conditions to provide a constant acceptable internal climate.
Rotating and Fixed Architectural Wind Cowls
These unique designs are very much a dominate feature of the building. At Vision we design, test and install natural ventilation turrets that are unique and bespoke to the project. Both rotating wind cowls and fixed architectural systems are designed to track the wind under all conditions over a 360o range to optimise air flow in and out of the building. Each design is configured to provide both intake and extract through the same roof unit or dedicated intake or extract depending on the design requirements.
This is a design drawing for the natural ventilation wind cowls we designed and developed for the University of Nottingham’s Carbon Neutral Laboratory, which used 80 wind cowls set between the timber turrets:
Read the University of Nottingham full case study
Our designs are developed through a series of stages starting with the architect’s concept, conventional air flow calculations are then produced to determine what the building needs to maintain a constant temperature and CO2 levels under full occupancy. The bespoke design is then Computational Fluid Dynamics (CFD) modelled and structural calculation produced to ensure stability under extreme wind conditions without compromising the aesthetics of the units.
For over 20 years Vision Ventilation have pioneered the use of large-scale architectural wind towers and are present on many high-profile commercial buildings.