045 euros per square metre outside work and 2

Offices, buildings or housing low consumption comply with the BBC-Effinergie label in phase with the future RT 2012 taken in application of the Grenelle environment, do not run the streets. They are the work of pioneers who anticipated the standards by ecological activism and curiosity. The architect Pascal Gontier is such, alternative solutions and insulation reinforced without relitigation of the pleasure of living. Its last operation performed in the 20th arrondissement of Paris to the SIEMP, company tool of the city of Paris, meets all the requirements of the BBC label without leaving the budget for social housing, the price of basic arbitrations and cyclical adjustments. Last study in 2006 and delivered in the fall of 2010, this 17 rental units, a local commercial, out to 2.045 euros per square metre outside work and 2.700 EUR per square metre useful in construction cost duty-free stack in the target of this social sponsor. The gap between these two values is particularly due to the thick envelope implementation to achieve a high level of isolation, first unavoidable step on the path of the label.

Economic compactness

The thick coat dresses sails reinforced concrete consists of 26 cm insulation and of exterior siding in untreated larch, "naturally sustainable gasoline", said Pascal Gontier. With internal versioning, which is part of the performance, the wall reached 50 centimeters thick. For good measure, the Windows are equipped with triple glazing, allowing large openings. "The effectiveness of the envelope translates surfaces glass of the order of 24 of living space against a ratio of 17 generally accepted and recommended by the RT 2005 in force", welcomed the architect that is not sacrificing the light energy performance and for whom "the Thermos bottle is not inevitable." The undeniable extra cost this coat and the woodwork is offset by a simple volume that is not to displease him, and repetitive arrays. It assumes the image of the wooden box come straight from the Austrian Vorarlberg - region known for its efficient and sustainable architecture - and relativizes his strangeness by arguing the localization in the islet Fréquel-Hondarribia, instead of sections of wood and unsanitary houses workshops being renovated under the label of "first écoquartier" Parisian Backed by a neighbour and aligned on a crossing, the building provides transition to the heart of island partly shaved and tomorrow inhabited around a public garden. Split into two blocks of unequal height by a Court of entry, book compensates the handicap of a main facade to the North by multiplying the directions to capture light and Sun. All housing plans, Studio 5-piece, are multi-orientés, if not through. Most bathrooms have even a window. So, a single cage elevator and staircase serves the entire, the small plot being connected to the great by two levels of gateways properly disconnected facades to avoid thermal bridges, pet peeves of the design. The operation is draws its economy. The form factor is therefore essential to be able to afford the benefits required by the BBC requirement.

Technical substitutions

The other route of access to the label through alternative, while expensive heating systems, but that substitute for conventional facilities. Heating is provided by a system of Canadian wells which organizes a water loop 30 meters of depth coupled with exchanger supplying a ventilation double flow needs being significantly reduced by the fact the overinsulation and sealing. The boiler, the water circuit and conventional heater body are thus saved, releasing additional walls. Sanitary hot water, it is produced for half by rooftop solar panels and a more expensive than an electrical make-up natural gas boiler. Overall consumption is thus located just below the required threshold of 50 kWh per square metre and per year. No remains, however, that these innovative equipment represent a cost and it took trim some internal benefits, for example generalizing flexible flooring over more qualitative. But the light and the views are beautiful inside, and it is for Pascal Gontier essentially.

Finally, the cost has still increased by the timidity of the companies: innovation is fear and many tend to increase their prices, mainly fearful of air tightness tests. In this case, only one replied Francilia here who took the risk of the BBC to position itself on a market for the future.