Architectural Future in the Present: Maison Air et Lumière

Natural daylight and fresh air are a priority for the entire building, which is evidenced by the unusually favorable ratio of window area to floor space. The windows account for almost a third of the building's floor space, compared to the usual 20%, which is indeed a significant difference.

A family house located in the village of Verrières-le-Buisson near Paris is the sixth and, so far, the last experimental house in Europe built to support the development of the active house concept. These houses emphasize a comfortable and healthy living environment with respect for year-round access to natural daylight and fresh air. Since the end of August, new residents can experience what it is like to live in this visionary work for a year.

Natural Light and Air as a Symbol of a New Era of Living
Natural daylight is the foundation of our physical and mental health. With a ratio of window area to floor space of nearly 1:3, the Maison Air et Lumière project feels very open and inviting. Its rooms are filled with sunlight throughout the day. "The house will be a pleasant environment for living, where, thanks to the quality of its space, natural light, and location, people will want to live. They will reconnect with the essence—air and natural daylight," says Michel Langrand, General Director of VELUX France, the main investor in the project. The construction of the house also placed great emphasis on the ventilation system. Despite the warm summers typical of the region, the house does not require air conditioning, thanks to the appropriately chosen geometry of the rooms and a well-thought-out ventilation system. The simple hybrid ventilation system combines mechanical ventilation with heat recovery with automatically controlled ventilation via façade and roof windows. The shading of the house is also automated, ensuring optimal conditions within the house throughout the year.

Architectural Concept
Maison Air et Lumière is designed to form a harmonious whole with its surroundings. The slope of the site determined the arrangement of the individual floors, and the slope itself creates a transitional level between the garden and the upper floor (entry to the building is on the mezzanine level). The modular concept of the house allows it to be adapted to different sites as well as integrated into other contexts, such as terraced or urban houses. These adaptations facilitate the creation of further variations. It does not matter whether the house is small or large, located in a city or in the countryside. The flexibility of this concept allows for changes in the type and number of modules, thus transferring the principles of comfortable living, energy saving, and environmental quality of the Maison Air et Lumière house to many different contexts.
The floor area of 130 m² spans one and a half stories, with all spaces under the roof fully utilized. By using integrated design that considers requirements for architectural quality and energy savings, the Maison Air et Lumière project emphasizes interior comfort while respecting energy and ecological goals for new family houses applicable after 2020.

Principles of an Active House
Maison Air et Lumière meets all the principles of an active house. Requirements for low energy consumption, quality indoor environment, and ecological sensitivity are integrated into the building design. The active house requirement framework (radar) shows a multi-criteria assessment of the house—how all parameters of each requirement are balanced. This allows for a holistic approach and an overall view of sustainable buildings. It also indicates that the parameters of active houses rely on active choices within each parameter.

The first edition of the house assessment in the form of a radar for active houses expresses parameters defined based on the Active House Specification published in April 2011. The displayed radar chart is based on both theoretical assumptions and calculations derived from input data provided by the project team and is then generalized. The evaluation reflects the current development status of the project and will gradually be supplemented with data collected during the testing period.

Intelligent Slopes for Comfort and Savings
A unique feature of Maison Air et Lumière is the intelligent use of the sloped roof, which combines comfort and energy savings. The roof's optimally designed slopes enhance its capacity to capture sunlight and heat, thus actively contributing to the building's energy properties. The orientation and angles were chosen to allow solar collectors and photovoltaic panels to operate at maximum efficiency. "The roof effectively becomes the fifth façade, regulating the indoor environment and optimizing the supply of light and air. At the same time, it represents a striking aesthetic element. Thus, the project is based on the concept of modular architecture with a sloped roof, where individual modules can be combined as desired," explains the project architect, Ing. arch. Klára Bukolská. The house can be adapted in future projects to suit various geographical, climatic, urban, and budgetary situations while still adhering to the principles of comfortable living and energy efficiency.


Daylight
Particular attention has been paid to daylight to ensure the physical and mental health and well-being of the residents. The focus has been on enhancing visual perception of indoor spaces and achieving energy savings by reducing the need for artificial lighting. The amount of daylight and the quality of its distribution were verified through simulation in the VELUX Daylight Visualizer 2.


Ventilation
Depending on the season and weather conditions, ventilation is provided by a hybrid ventilation system that combines the benefits of mechanical ventilation with heat recovery in winter and automatically controlled natural ventilation through open windows in summer (supplemented by mechanical extraction in the bathroom and kitchen).

Energy Design
The energy design of the Maison Air et Lumière house is based on maximizing the use of renewable resources (solar energy, natural light, fresh air) to minimize the need for air conditioning in summer, reduce energy needs for heating in winter, and limit the need for artificial lighting. This combination ensures a neutral impact on the environment as well as maximum comfort for residents. The timber construction with high-quality thermal insulation is built on an insulated concrete slab and features a window to floor space ratio of nearly 1:3.
Due to its mass composition with a sloped roof, the building is compact and very well insulated. The internal walls of the house are covered with terracotta cladding, significantly improving the thermal inertia of the building to ensure a stable and comfortable room temperature. The effectiveness of the insulation combined with heat recovery and thermal gains from sunlight entering through the windows limits the need for heating to a minimum. Heating and hot water are provided by a heat pump connected to VELUX solar panels and low-temperature underfloor heating.

Artificial lighting, household appliances, and multimedia equipment have been selected based on their low consumption. In addition, the washing machine and dishwasher are directly connected to both hot and cold water supplies to further reduce electricity consumption.
All electricity consumption will be balanced by the supply from photovoltaic panels with a total area of 35 m² integrated into the roof. With standard building use, the overall energy balance will be positive.

A Young Family Full of Enthusiasm
Since the end of August, the four-member Pastour family has been residing in the house for a trial period of one year, testing the new home in practice. The couple with two small children plans to build a bright, low-energy modular house. For them, Maison Air et Lumière represents the perfect opportunity to compare different options and bring their project ideas to fruition. "The quality of living in the house means a lot to us. The quality of air is especially important due to allergies that occur in our family. Moreover, one of our sons is asthmatic. We would like a house full of light to lift our spirits both in summer and winter. Having an eco-friendly and self-sufficient house is an absolute priority for us," emphasizes Mr. Pastour.

The Pastour family moved into the house at the end of August. They are looking forward to a year of living in a home of the near future, which will become a reality in 2020 when the revised EU directive comes into force, requiring all houses to have energy consumption close to zero.

The residents are captivated by the unprecedented combination that connects design with modern technology. Aesthetic features thus become practical and economical. To minimize electricity consumption as much as possible, the house has an active façade with sensors that respond to changes in external temperature. For example, if the sun is too intense during the day, the awnings automatically retract, or in the evening, the windows automatically open to naturally cool and ventilate the house. For owners who enthusiastically admire new technologies, such a connection is a dream come true.

More information can be found at www.velux.com.