Prevailing Wind Analysis_London
academic work UCL 2012 Naturally Ventilated Crafts Centre in Gabriel’s Wharf, London (“Natural and Mechanical Ventilation of Buildings“ module) Brief: Design a naturally ventilated, building containing both high- and low-occupant density spaces. Location: central London. Simulate the thermal performance of the designed spaces in TAS. Software: TAS, AutoCAD, SketchUp, Artlantis, Microsoft Excel + Word, Adobe InDesign + Photoshop, Corel Draw. Site: “Gabriel’s Wharf Court” is a 2750m² flat site located on the Queen’s Walk, Thames’ South Bank. It is an enclosed court-type area, bounded by single-storeyed buildings located on the eastern and western side. Gabriel’s Wharf Court is a popular destination with restaurants, cafes and small retail studios, some of them overlooking the river. The character of the area is given by the human scale of the modules and the activities happening inside the court - craft-type objects are on display (clothes, footwear and jewellery, wood sculptures).
Google Earth Map_1/500
Environmental analysis: • Thames - milder microclimate due to the huge thermal inertia of the water reservoir and the high cooling capacity of the water; • Adjacent park – microclimate providing seasonal shading; • Prevailing wind in London is a West-South-Western one. In Summer, there is little wind speed from the North, so the possibilities of cooling through this side of the site are limited. • Solar activity and shading – there are no tall buildings casting shadow over the site, except for the adjacent western building; • Pollution and noise – minor issues.
Site plan_1/500
View of court and western adjacent building Proposed module concept View of court with existing activities
Typical existing module
Architectural concept_Crafts Centre: The main goal of the project is to preserve the character of the site and to create a lively and thermally comfortable environment in which people can gather throughout the year to learn and participate in the contemporary and traditional- craft proHuman-scaled module proposed concept
Proposed module ventilation concept
Building Typology and Site Occupancy The designed building is a Crafts Centre is placed on the northern half of the site known as Gabriel’s Wharf Court. Spaces of Centre include: • Interactive workshop / seminar spaces; • Exhibition and sales spaces; • Lounge and information hall; • Restaurant and cafes; • Library; • Office / computer rooms. West side building – three storey building, containing Workshop/ seminar spaces located in 5,0 x 5,0 x 3,0 m modules with 1, 2 or 3 meter setbacks that act as balconies for the upper floors and total or partial glazing, depending on the activity happening inside; Total Area = 670 m². East side building – two storey building with glazed surfaces in most part of the west and east façades, in order to enable the user to have access and clear view from the atrium to the park. The modular spaces are used for a number of cafes and restaurants. Total Area = 360 m². East Atrium – a tall and broad space that acts as a buffer between the two buildings. It is used as a lounge / exhibition / occasional workshop area. Fully glazed, with operable windows that allow a high ventilation rate. Total Area = 370 m². Western Atrium - three storey high space connecting the western existing building painted blind wall with the new design. Space is used for exhibitions. Total Area = 120 m². Total Crafts Centre area = 1520 m². General occupancy schedule: The different spaces are zoned according to the activities happening inside and the commercial-use potential of the area. West building (Workshop/seminar building) and West Atrium —all seasons : 09-17. East side building (Restaurants building) and East Atrium —Winter : 09-19 | Summer : 09-21. Environmental design strategy The main design strategy is to create two thermal buffers protecting the internal spaces from direct contact with the cold or hot outside environment – two atrium type areas. The Central and Western Atriums are tall and wide, unheated spaces that are thermally close to outside ambient temperature, yet create a shelter from the wind, direct sun heat or the rain. • Existing opportunities and challenges. The surrounding buildings limit the actions of wind from the western and southern direction, so major prevailing wind will not affect the project.The neighboring park provides fresh air for natural ventilation and a seasonal shading opportunity. The western blind-wall building (the London Studios)provides shading and blocks heat losses and wind from 1 direction. • Zoning. Different activities have different spatial and comfort requirements, therefore the design groups the similar ones into distinct volumes. Heating is only provided in spaces that people spend more time in (engaged in some kind of activity).
Environmental Concept_SUMMER_section[not to scale]
Aerial Perspective towards the Thames
Environmental Concept_WINTER_section[not to scale]
Ground Floor Plan(above)_Space Temperature Targets [not to scale]
First Floor Plan [not to scale] East-West section_SUMMER [not to scale]
WINTER
SUMMER <Non i tersectn ig n il k>
East-West section_WINTER [not to scale]
Details of external and internal wall_1/20
Second Floor Plan [not to scale]
Aerial Perspective from the Queen’s Walk Section through site_WINTER [not to scale]
Section through site_SUMMER [not to scale]
Casual heat gains Some of the heat-producing activities (light or medium work, walking) take place in the designed spaces, especially in the workshop building. Also, the restaurant’s kitchens produce considerable amounts of heat. Buoyancy-driven circulation of air In the absence of wind-driven ventilation (characteristic to all urban settings), the only natural ventilation viable strategy has to be buoyancy-related. Therefore, internal and external temperature difference must be directed to serve both heating and cooling requirements. The Crafts Centre is comprised of two main buildings (Eastern and Western) with different activity-related internal comfort requirements. Both participate in the same environmental strategy of creating near-ambient-temperature atria (Central and Western) protecting internal spaces from direct contact with the outside conditions. No heating is required in either of the atria, as the people passing through them are already wearing warm clothing coming from outside. Both atria are of near ambient temperature, with a design comfort target of 12-20°C (winter) and 21-28°C (summer). They are shelters from the wind or the rain but are not necessarily much warmer or cooler than the outside air, as they are intermediate spaces. This means that they cannot be considered “internal” spaces, and therefore all walls adjacent to them must be treated as external ones, having proper insulation.
TAS Model of Crafts Centre
Interior Perspective of the Crafts Centre