ECO BUILDING: LOW DENSITY HOUSING

ECO BUILDING: NATURAL PLAYGROUND ECOLOGICAL CITY BLOCK UTOPIA, BARCELONA// MAEBB - IAAC

INTRODUCTION

When considering what makes an ecological building, it is useful to see its physical incarnation as a snapshot of a larger network of metabolic systems. The materials that compose the final product are the results of not only the raw materials and transformation processes that they undergo, but the assemblage of industrial regimes that produced those materials.

Our project focuses less on shifting the paradigm around the visual appearance of a building, opting instead for a fairly simple massing strategy. Instead, it is the way in which the materials are deployed that create a truly new dimension of design. The building is composed almost entirely of wood, utilizing massive timber CLT panels, glulam columns, and raw timber struts. Each element deploys a different wood species, attempting to show the diverse range of properties that the material can perform.

BUILDING DESIGN

While we navigated through the design process, we made sure to document and maintain a running archive of each evolution of our model massing. We had some idea of a negative space our courtyard at the center from the beginning, which can be seen in step 1 above. We also wanted to allow for street level access to the first level, which could serve as a semi private cafe terrace that is elevated above the street. In step 4, we started to incorporate the scale of apartments that we needed to provide, which informed us of how many levels we should have. Step 6 shows how we eventually wrapped these apartment units around the courtyard in a ‘mustache’ configuration. Steps 7-9 detail how we refined this shape to conform to the spatial needs of circulation as well as balcony articulation.

STRUCTURE

The structure of this project is based on the material properties of the types of wood utilized within it. While the overall appearance and scheme changed many times throughout the design process, there was always an effort to address different structural needs with discreet material assemblies. The first floor was always intended to be open, public, and inviting to allow neighbors and city dwellers to occupy the space of the building.

To create this arcade of sorts, we established a foundational geometry to link all of the columns, creating horizontal deflection resistance in addition to the compression resistance that was already being generated and create a more simplified CLT ‘house of cards’ structure in the upper floors.

ENVELOPE

The envelope of the building creates a uniform exterior surface, performing several functions simultaneously. Structurally, the cantilevered balconies that make up the irregular shape of the facade get supported by the conituous wooden vertical strips. The strips also become thicker in the south facade, and thinner on the north, providing appropriate shade protection from the harsh Barcelona sun. Based on privacy needs, a pattern was generated to provide more or less visibility. The envelope also serves as a handrail attachment and armature for gutters that connect to the balcony planters.

The envelope was generated through a combination of manual assessment and grasshopper assisted design. First, each elevation of the building was placed on a grid with a corresponding number related to the amount of privacy each area needed. A simple scheme of wooden strips was then placed over the undulating facade, and then culled according to the value of privacy.

In previous iterations, the facade was composed of a layered system of different thicknesses of wooden slats that created a dynamic movement. Later versions combined this into a single layer to save materials.

The envelope of the building creates a uniform envelope which performs several

Structurally, the cantilevered balconies that make up the irregular shape of the facade get supported by the continuous wooden vertical elements.

The vertical elements also become thicker on the south facade, and thinner on the north, providing appropriate shade protection from the harsh mediterannian sunshine.

Based on privacy needs, a pattern is generated to provide more or less visiblility.

The envelope finally serves as a handrail and attachment system for balconies and planters.

After conducting an exhaustive energy analysis, we came up with several strategies to offset the power usage of our building in an effort to waste as little energy as possible.

Most importantly, our Biomiler waste to energy system helps to drastically reduce the heating needs of the building during the wintertime by using a resource that is already produced naturally on site. The large amount of both human and food waste that the residents produce is usually budgeted into the water and energy usage of the building, and are a net loss in terms of how we manage to properly dispose of them. Instead, we can take those products that seem like waste and turn them into a source of energy. The heat produced during the exothermic chemical breakdown process is powerful, and when one considers just how much waste 300 people can produce, it starts to seem less like a wild eyed idea and more like an obvious solution to connect the material flows of the building back into one another. A waste problem becomes an energy solution.

WATER CYCLE

Water from the municipal tap is used in bathroom sinks, showers, WC and laundry, as well as the kitchen sink and dishwasher. Grey water from the bathroom sink and shower as well as laundry is collected and filtered organically with plants. The gray water from the WC and kitchen is sent to the municipal treatment plant.

Some gray water treated from the plants is used for the radiant floor heating system before being stored in the cistern which waters the garden beds. Rain water from the street is also filtered through plants and then stored in the irrigation cistern as well as the water collected through the rainwater gutter system is also stored in the cistern. Ultimately a very small amount of waste water is diverted into municipal treatment.

FACADE DETAIL

The facade is connected to the building with metal ‘L’ plates which extend outward and also hold planters that run throughout the edge of the floor. These ‘L’ plates are screwed into the planters from one end and into the CLT floor slab on the other end. The facade fins which run continuously from top to bottom have attached the rainwater gutter pipes attached to them which also water the edge planters. The cantilevered balconies for different apartments are separated by bigger planters with lattices for climbers.

BASE DETAIL

The column on the ground floor is developed by splitting a column of a large size into multiple smaller columns. The columns have a concrete foundation and are bolted into the foundation with ‘T’ plates. The angled branches helped distribute the loads over a larger span while leaving the ground space free.