The first criteria for choosing an insulator are ecological: renewable and recyclable raw materials, little gray energy and C0 2 emissions for their manufacture, low impact on indoor air quality and health. From this point of view, plant insulators have a much better eco-balance than mineral wools or insulators from petroleum by-products. If it comes to wood cladding then be sure that you can have the best choices made there.
The performance of the insulators is conventionally measured by lambda or thermal conductivity ability to transmit heat. During the hot season, when the walls must contribute to avoiding overheating, we will focus more particularly on the thermal capacity or the phase shift of the insulators, which allows them to store the heat to restore it with a certain phase shift. The performance in sound insulation is also to be taken into account. All these criteria are found in the table published on the page which insulation to choose? You will also need to choose the most suitable insulation for your site: implementation possibilities, nature of the media, not to mention the price.
Insulate from the outside?
Although this last option is not very developed in France, it has the advantage of ensuring continuity of the insulation on the entire facade, which avoids most of the unresolved thermal bridges with insulation from the inside floors, ceilings and shear walls. It also makes it possible to conserve all the benefits of the inertia of a solid wall in the case of the main residence to be avoided for a second residence, which will take too long to warm up in the cold season.
The difficulty consists of finding insulators that are resistant to external constraints and capable of ensuring the stability of a coating making it possible to regain a traditional external appearance. The expanded cork boards are perfect for this purpose. It is also possible to use fiber plates or wood fiber panels capable of receiving a coating.
Other possible solutions:
- The screwing of reed panels on which will stick a plaster.
- A thick insulating coating (based on hemp, cork or perlite) sprayed with a compressor and covered with a finishing coat.
These solutions, whose implementation is delicate, are rather reserved for professionals.
Inner insulation: bulk, rolls or panels?
Flexible panels cellulose, felted wood, hemp, linen and rolls hemp, linen are easy to implement and well adapted to the renovation: they are inserted between frame elements and are fixed with some staples. Harder insulators cork, wood fiber or cardboard straw boards should not be installed between frame studs as they may not fit tightly together. They must be glued adhesive mortar or nailed directly to the wall. they can then receive certain plasters, wallpaper or wall fabrics.
Bulk insulators are the least expensive, but their implementation between the wall and a facing panel is delicate and is done by insufflation with pressure which must be sufficient to avoid any subsequent settlement. The boxes must be well sealed and no obstacle should interfere with the passage of cellulose.
Latest recommendations: pay attention to the handling and cutting of some insulators that produce a lot of dust: wear a mask. And put a lot of care in the implementation, just as important as the choice of insulation.