Massive House I
Award “Equivivere per un’architettura sostenibile”
Arch. Massimo Rodighiero
Arch. Roberto Gaeti
Ph. Andrea Martiradonna
The creation of a new residential building in Gussago, in the province of Brescia, has had energy saving as its theme, a topic that gathers great interest in the public opinion that is increasingly aware of ecological and economic aspects.
Architectural aspects and composition
The bioclimatic need to concentrate service areas in the north (stairs, kitchen, toilet) and the living areas in the south, in order to facilitate passive solar gain, imposed a central corridor planimetric diagram. On explicit request of the client, the house has been designed to be quickly and easily divided into several units, thus supporting the evolution of the household’s composition and consequently avoiding the abandonment of the building or the creation of costly adaptations. The overlap of toilets at the floors and the use of equipped walls then allowed to minimize building assistance and the necessary technical slots of the hydo-sanitary plant, thus helping to speed up the construction and related cost reduction.
Much attention has been paid to the reduction of the architectural barriers, projecting spaces that are accessible to people with mobility problems. The correct sizing of the accessory compartments and the installation of the stairlift linking the basement to the ground floor and this one to the first floor, allow the full passage through the interior and exterior of the building to people with disabilities.
Typological and formal aspects
All floors and outer walls of the two emerging levels are made of prefabricated panels made by Styl Comp, equipped with a ventilation circuit adequately insulated and isolated from the outside. This is an advanced pre-fabrication, of thermal break and reduced form, that facilitates handling and transportation in areas that are not easily accessible by truck, designed in close cooperation with the Rodighiero studio. Particular attention was paid to the shape of the artefacts developed to hide the supporting structures (beams and columns) in the thickness of the floors and walls, reducing as much as possible the wall-ceiling and wall-covering thermal bridges. Using an engineered concrete with high mechanical strength and permeability insulating and breathable inerts, has allowed to increase the isolation and maintain reduced weight and thickness of the wall, facilitating the traceability of the plants.
The entire inhabited envelope is therefore completely breathable and permeable to water while ensuring a surface mass that is adequate to the exploitation of the thermal inertia for a cost-free cooling of the rooms. The use of these types has led to a phenomenal enforcement speed (given the site and weather conditions, the furnishings were delivered 13 months after the start of construction) obtained without the use of skilled labour. The cost of construction was particularly low for the type of house plant and equipment made, and external coatings provide reduced maintenance.
The modern and linear style of the building is characterized by the free patterns of the openings, that are reduced to a minimum and measured on the most favorable solar exposure and the creation of views towards the surrounding hillside. The architectural solutions employed are targeted to optimize the link between the surfaces of the heated casings and their volume, in order to reduce energy losses. Volumes “glimpse” into the sunlight, silhouetted against the surrounding landscape, creating overhangs and shades specifically designed to participate in the maximum energy efficiency, especially during the summer. The bioclimatic concept of the project was inspired by the desire to reproduce the model of the “House of Stone” which can then make the most of the thermal inertia to improve summer cooling without having to resort to the use of expensive air conditioning systems. The material differentiation of the exposed surfaces (ventilated wall in the south, stone coat facing the north) makes perceptible the massive concept of the building while the reduction of the openings to the north and expansion of glazing to the south show the need to exploit the passive heat gains given from solar radiation in the winter. On the basis of a careful study of the climate of this particular hillside area, it is clear the need for making buildings that are adequately insulated for the winter and that guarantee, at the same time, cool rooms in the summer. The bioclimatic concept of the project was inspired by the desire to reproduce the model of the “House of Stone” which can then make the most of the thermal inertia to improve summer cooling without having to resort to the use of expensive air conditioning systems.
A building that is energetically and environmentally sound must take into account local traditions to enhance the use of materials that are readily available in the area in which it is set, in order to decrease the cost of transportation and the air pollution linked to it: from here the decision to use, for this new complex, stone and concrete from the district of Brescia, broadening the concept of “saving” and “green” also to economic and social aspects. The cost savings may be the energy savings. Hence the use of local materials, which, interpreted and developed, continuing a building tradition that is always sustainable as the expression of specific environmental, climatic and socio-economic. The material differentiation of the exposed surfaces (ventilated wall in the south, stone coat facing the north) makes perceptible the massive concept of the building as well as the reduction of the openings to the north and expansion of glazing to the south shows the need to exploit the passive heat gains given from solar radiation in the winter. The high level of insulation (U cladding and roofing in the current section of 0.24 W / m. ° K) was obtained through the precast elements described above, so that they minimized the use of insulating materials of chemical oil origin.
Bioclimatic and plant functioning
The plant design has assisted the bioclamatic concept that is behind the project: the construction of a building that is on one side well insulated to meet the rigid winter temperatures and, on the other side, massive enough to allow, together with the natural ventilation of the rooms, a free cooling of the rooms in summer conditions. It was therefore created a plant of radiant floor heating and cooling systems, able to exploit the mass of the walls and floors and the contribution of free energy provided by the solar heat installed on the roof.
The plant is equipped with dehumidification and double flow forced air exchange with heat recovery. The result is a certificated very small primary energy need (28.4 kWh / Sqmt year -Class A-), while the direct experience of the users has registered an internal-external delta of almost 9 ° C in summer, which has rendered almost unnecessary the use of the cooling plant.