What is a passive house? Is it quiet? Is it energy efficient? Does it smell better?
Passive House is considered the most rigorous voluntary building standard in the residential and commercial building industry today. Passive homes often consume 90% less heating and cooling energy than convential code built homes where the Passive House Institute performance building standard is the only internationally recognized, science based energy design standard delivering this level of performance.
5 principles central to Passive House design and construction:
- Super insulated home
- Air tight building envelope
- High performance fenestration (windows)
- Thermal bridge free detailing
- Heat recovery ventilation
Passive House design starts from the beginning of a project where owners work with their architect-designer and custom home builder to come up with a lifestyle home that the owners desire, in a budget the owner can afford. The above principals must be included in the architect-designer’s thought process.
Key items for the owner, architect, and builder to consider are
Running an engineering model of the home at the preliminary design phase based upon proposed wall, roof, floor insulation, window selection where Solar Heat Gain Coefficient of the glass is known, and U Value of the overall windows are known – this will provide a first pass at the energy efficiency of the home.
Overhangs over windows and doors are very important for durability of the windows and doors along with cooling savings in summer.
Selection of MEP (Mechanical – Electrical – Plumbing) Engineer is very important to the process. There are significant shortcomings to the mechanical engineer’s ACCA design manual for sizing of HVAC equipment which generally over sizes equipment as indicated by the WUFI passive house design modeling software by PHIUS – the Passive House Institute US. Using the PHIUS model, equipment is not oversized, is more energy efficient, and is combined with a whole house fresh air ventilation system.