Isolation: the fundamental component

Before talking about clean energies to be used in your house, anyone should pay extreme attention to the isolation performance.

Indeed most of our house have been designed with poor isolation performance and new initiatives are popping up to work that around such as bioclimatic house, or the passiv haus institut, etc.
The latter evoques the possibility to give-up any heating system, or reduce it to a very small unit.

To summarize my thoughts around that topic, I would advise the following best practices:

A good isolation means a complete separation between outside and inside the house. The best isolation performance is given by non-moving air. In order to deliver a global efficiency, the following components should be handled with care:

• the external walls
• the roof
• the floors
• the external doors and windows using double or triple glas thickness.
  
• thermal break of the balcony & terrace attachments to the house
• protection of the house from the dominant winds
• the ground fundations
  

Based on my current understanding, I would recommend to proceed with the following techniques:

• The external walls should be isolated along with 3 layers.
  Layer 1, in touch with external air should be rather protective from rain and shocks. I would recommend the use of wood or stone.
  Layer 2 (inner layer) should be made of thermal isolating material (polystyrene, woodwool, rockwool, etc.). You can qualify the thermal performance using basic technique: this should be warm when touched...
  Layer 3 is facing the internal air of the house. This layer should support the house structure, including the floors & ceilings, and should provide high thermal inertia, with good thermal infrared performance. You can qualify such material with heavy weight concrete walls (cellular, high density, etc.), or, even better, with bricks (monomur, etc).
  
  The humidity control issue should not be missed here. I invite you to read my next posts on it.
  
  
• The ground fundations have to be well isolated too. New techniques have been explored by our friends building a passive house in Nice (French Riviera). The most convincing demo is given by the Isoquick german company.
  
  
• Regarding the roof isolation, I would be very cautious in front of those new thin layer materials. Provided that the non-moving air is the best isolator, the thicker the better... I would rather recommend either the use of rockwool, or woodwool, or even polystyrene (less bio-ethical).