Passive Homes are homes designed to have comfortable living environment in both winter and summer whilst having non traditional heating systems and they do not require active cooling. This is achieved through high insulation values, low air leakage and building details that ensure minimal thermal bridges.

Houses built to meet the Passive House standard have an upper limit for total primary energy demand for both space and water heating including ventilation and electricity usage not exceeding 120kWh/m2 year. The Passive House standard for space heating is 15kWh/(m2 year)

In Ireland the Passive House Standard can be achieved by Super-Insulating Walls to below 0.18 W/m2K, insulating roof and floors to below 0.15W/m2K and using windows and doors with a U value of less than 0.8W/m2K. This standard also requires that air tight construction must be used with air changes restricted to 0.4 changes per hour.

In order to ensure this air tightness value buildings will need to have pre-completion air tests conducted which will determine exactly the air tightness of the construction. 

Passive Houses would be rated A2 under the New Building Energy Certificate Scheme as introduced in January 2007 and if as little as 400 of these units were to be built there would be a 3.29GWh energy and CO2 emissions  savings in just 1 year.