Location: Trent-England
Date: February 2012
Competition: ISOVER MCH
project: Sustainable community within the regeneration program 

Social- economy strategy

Current recession circumstances cause public administrations to have less and less money to regenerate areas of the city, providing them of all the necessary services for its citizens. When reconverting ex-industrial areas into residential ones, one should rethink not only about the housing system. It is fundamental to consider managing the surrounding facilities that should ensure a suitable living to the new inhabitants of these suburbs. The socio-economical solution I am proposing consists in creating micro communities within cities, where citizens would feel part of this community and share public spaces managing them directly. The contest project area will be a self-managed micro community with a certain autonomy degree compared to the rest of the city. Public facilities will be flexible buildings in their usage and in time. They will be administered by citizens themselves depending on their needs and sharing their own resources to make the most of them. The most important part of this design strategy is to minimize mobility with resulting reduction of CO2 emissions, apart from taking advantage of one’s time, saving money and reducing stress.

Site plan management

Existing warehouses in good conditions will be re-used to create public, community based facilities. In this way we take the energy contained in existing buildings. They will maintain their structure – 7250m2 of valuable surface. Vertical connections will be made on the external part (half-conditioned space) in order to affect as little as possible the structure, and to leave flexibility of usage over time across all floors. Community facilities will be installed in the inside, such as:

• Library (community)
• Nursery (community)
• Working spaces (for rent)
• Fitness spaces (community)
• Art and music workshops (for rent)
• Cultural spaces for meetings and theatre (community and/or for rent)

The core of the project will take place exactly between these two buildings, key points of the area’s liveliness. This will be a big, covered garden-square where citizens will have the opportunity to enjoy a Mediterranean climate with trees that would never be able to grow in Nottingham’s outdoors. The whole project area will be accessible only by bicycles and pedestrians – although in case of emergencies or due to logistic reasons transport on wheel will be possible. Regarding the residential area which will be designed in the second stage, I am planning to use the same building typology adopted on the first lot, and to designate it temporarily as a sport area (soccer fields, volleyball, basketball etc.) The existing basin will be cleaned up and re-used as a water sports area. The green section will have more intense vegetation on the west border to improve the park’s acoustic comfort.

Architecture strategy

The idea is shaped through an exterior shell which creates a half-conditioned space containing private and community facilities. Each greenhouse unit is big enough to accommodate between 4 and 6 households of 2 to 6 people each. These people would share a great deal of half-conditioned community space where they would relax, kids would play and microclimate would be better than outdoors. Also, premises would be shared between people to minimize waste and to make the most of clean-produced energy. On the inside of the greenhouse, not only would the microclimate be better but also would it create a shield against rain and wind. This means the housing modules should not necessary be waterproof, and their prefabrication, modularity and placement would be simpler and faster. Thanks to the ­­greenhouse our modules need not be air and water tight. They can be breathable and then have a better indoor air quality. The housing units are made of totally equipped prefabricated elements – facilities, finishes, and cladding. They can create differently sized housing units that can grow during time to adapt to people’s needs. On the housings covering, orchards modules could be installed to produce vegetables and enable a more sustainable lifestyle. Through the creation of the greenhouse we can afford to decrease the acclimatized surface and save energy and the housing’s building costs. It would also leave to the citizens a great half-conditioned private surface that can be used most of the year. The basic housing surface (1 room) is 50 m² acclimatized + 75m² half-conditioned. Each added module on the ground floor is 18,48m² acclimatized + 7,92 m² half-conditioned, and 12,50m² acclimatized and 6,50m² half-conditioned on the other floors.

Bioclimatic elements

Through bioclimatic concepts of passive solar energy use we achieve a climate improvement in our house and we save the cost of insulation the building.

• The greenhouse makes our house to be in contact with higher temperatures than the outdoor ones, allowing higher values of thermal transmittance compared to a traditional construction.
• The greenhouse concrete floors accumulate heat during daytime and release it during nighttime, decreasing thermal jumps. Also, indoor vegetation increases thermal inertia, helping us to create a more stable climate between day and night.
• Cross-ventilation with south and north enclosures allows to lower temperatures during summer time.
• The high insulation level and the reduced housing form factor minimize energy loss.
• Big windows facing south attract solar energy directly, and plaster boards with high thermal inertia placed on the floors gather this energy releasing it during nighttime.
• On the north facade there are small openings which allow crossed-ventilations during summer while minimizing energy waste during winter.
• In the mixed-use building there will be a mixed system of direct harvesting through windows and indirect harvesting through a trombe wall.
• Windows will have orientable blades to allow the user to adjust the quantity of sunlight he wants to receive.
• The passive, trombe wall harvesting system uses the existing concrete structure to gather heat and release it on the inside of the building.
• The 15cm concrete wall thickness provokes a 5 hours thermal lag, which is perfect for a diurnal use building. If the sun sets down at 4pm, we will have a natural heat source until 9pm.

Material & environmental impact

Greenhouse: Main structure: metallic tubular profiles. East-west enclosures and covering: 7 layers cellular polycarbonate boards. North enclosure: fir wood sandwich boards and Isover ECO D 035 insulator. South enclosure: aluminum openable windows with double glass and air chamber. The greenhouse function is to accumulate heat and make our housing to exchange its indoor temperature with a more suitable climate than the outdoor one. It doesn’t have to be a sealed and isolated space. The greenhouse structure does not have a very low environmental impact in its construction, but it allows us to create living units which require a lower use of materials. This makes it have a lower environmental impact, and thanks to this architectural element we save a lot of energy to manage the housing during its lifetime.

Insulated units: The main building material of our modules is ISOVER. The structure is made of laminated fir wood and wood OSB boards. As for the insulation material, half-rigid glass wool boards Isover ECO D 035 were used. They are made of recycled glass. The enclosures are also made of wood with thermal break and low emission double glasses with argon gas chamber. To minimize nocturnal waste, indoor enclosures have been created, made of wood sandwich boards and ECO D 035 insulation. The prefabrication and in-dry construction of our modules, in addition to the materials used, make the environmental impact to be a minimum. This is valid if we consider the hypothetical reuse or recycling of all its components when the housing will not exist anymore. This concept can be applied to the greenhouse too, for its structure is made in-dry.

Multi comfort house criteria 

To obtain a correct calculation of energetic balance it’s not possible to use simple-method programs such as PHPP or MCH-design. Our project has to be analyzed as a building (housing modules) inside another building (greenhouse). That’s why we used Balance, spreadsheet software developed by Universidad Politecnica de Catalunya. The thermal transmittance values of the different parameters ( adding up the housing modules values to those of the greenhouse) are the following:

• U north wall 0,10 W/m²K
• U top slab floor (roof) 0,12 W/m²K
• U bottom slab floor 0,10 W/m²K
• U south wall 0,13 W/m²K
• U easth/west Wall 0,12 W/m²K
• U window 0,68 W/m²K
• U greenhouse 1,10 W/m²K

We aimed to make the housing unit to function in a passive way.

During winter months without any energetic supply we manage to maintain indoor temperatures between 16,6 and 19,2. To reach temperatures between 20,3 and 22,2 we have to supply 8KW/h m2 for year. The housing modules prefabrication eliminates nearly all of the possible thermal bridges  caused by bad execution which quite often appear in traditional constructions. The ECO D 035 insulator is continuous and is only interrupted by the presence of doors and windows, it wraps each module fully, creating a totally insulated element and minimizing thermal and acoustical bridges. To calculate acoustic insulation we adoperated comparative method. The most unfavorable wall and slab perfectly full comfort acoustic parameters dictated by Multi comfort House Isover. The modules are very well insulated. By joining modules together, a double amount of insulation can be obtained among neighbors’ and among spaces belonging to the same user. The impact noise between vertical confining spaces (same user) disappears almost completely since each module’s slabs are independent and separated by a rubber gasket. Regarding protection against fire, the basic constructing system of wall and slab fulfills REI 60 requirements. This is because glass wool is not an inflammable material. It is A1 Class according to European classification of building materials reaction to fire. It is used as a passive protection against fire in buildings, so it maintains its mechanical properties even when exposed to temperatures above 1000C.

Natural lighting is achieved overall for most of the day, since the space is quite small (maximum depth is 5,6m) and has great windows facing south. In night modules the windows surface is 1/3 of the useful surface. In day modules the windows surface is 1/4 of the useful surface. In the bathroom and kitchen the windows surface is 1/5 of the useful surface.

Green energy production

 We considered generating energy through green systems to ensure full self-sufficiency regarding ACS, electricity and heating. To make the most of produced energy it was decided to go for a shared system between all users of each multi-family unit. In this way the energy management becomes more profitable and generates lower costs in building up the system, less waste and it avoids useless storage. It was decided to use a mixed system in order to lower the risk of unproductive days.

Mini wind energy system On the ridge of the mixed use community building 56 mini wind turbines will be installed. The dominating winds in the Nottingham area are coming from SSW. Average year wind speed 10 knots. Our building orientation allows us to make the most of these winds and its position creates a wind protected area where the housing units will be hosted. Because the covering is sloped, our mechanism performance improves, increasing the wind speed which generates Venturi effect when it deviates, hitting against the (sloped) surface.

Thin film photovoltaic panels Given that weather in Nottingham is rainy and with little sun, we decided to place amorphous silicon photovoltaic panels, which perform better in adverse orientations or in low-irradiance situations. These panels are placed on the covering of all the building, leaving some space in between them to balance shade and light entry.

Heat pipe solar collector To produce hot water and to support the installation of a radiant floor, heat pipe solar collector panels will be installed on the south facade. The vertical placing increases production during winter months and this panel typology does a good performance in cold climates compared to traditional solar panels. The water tanks will be communitarian, separated by ACS and the floor heating.

Hydrothermal eating exchanging temperature with the river water For the mixed use public building heating, a heat pump exchanging temperature with the river will be installed. This system performance is similar to a geothermal one, except it does not involve a large initial investment. The necessary electricity to make the heat pump work is generated through the wind and photovoltaic installations, thus the energy produced is totally clean and free.