passive house design

What is a Passive House?

Essentially, a passive house is a building that;

  • is so energy efficient is uses about 1/10th the energy of heating of a conventional building
  • you save typically €1,000 to €2,500 per year on heating costs (may equate to 10% off your mortgage repayments)
  • draught-free
  • always warm ambiant temperature constant 20 degres all year round
  • Permanent fresh and clean air
  • reduced noise infiltration
  • you can open the windows at any time!

How Much Does a Passive House Cost?

  • it costs 0% to 5% more to build, depending on your site, house size and design needs.
  • We will prepare a cost analysis to demonstrate your pay back time.
Your reduced energy costs should offset the additional capital cost repayments,You have a more valuable asset, Energy cost security, A comfortable house for ever and you have done the right thing for the environment.


What is PHPP ?

We are currently using Passive House Planning Package 2007 for most of our projects as a tool to optimise the design in terms of energy performance and compliance with new building regulations.

The PHPP is primarily a tool for verifying a building has met the “Passiv Haus” standard in terms of the specific heat requirement and overall primary energy requirement.

It is also a very practical tool for optimizing designs, e.g. by varying insulation thicknesses, window size and types, and building orientation and geometry, you can see the effect these changes have on the final heat requirement, and thus adjust the design.

The PHPP looks at the building fabric and key components in a passive house and includes tools for:

  • Calculating the U-values of components with high thermal insulation
  • Calculating energy balances- Designing comfort ventilation- Summer comfort calculations
  • Calculating the heat load (including Irish climatic data)
  • And many other useful tools for reliable design of passive houses

The passive house standard is a specific construction standard for buildings (any building) which results in good thermal comfort conditions all year round without traditional space heating systems and without active cooling.

The energy requirement of passive house is:

  • Annual space heating requirement of 15kWh/m2a treated floor area
  • The upper limit for total primary energy demand for space and water heating, ventilation, electricity for fans and pumps, appliances and lighting not exceeding 120kWh/m2a, regardless of energy source
  • The air leakage test results must not exceed 0.6 air changes per hour using 50 Pascal over pressurisation and under pressurisation testing.


For more information contact us.

loic Dehaye passive house designer