Passive House

Passive House

www.leonardo-energy.org

Definition

The term ‘Passive House’refers to a specific construction standard for residential buildings with good comfort conditions during winter and summer, without traditional heating systems and without active cooling

AcknowledgementThis presentation is based on material contributed by Erwin Mlecnik from the Passive House Platform (PHP) Belgium.

The graph on screen 5 comes from PHI Darmstadt


Scientific definition

“The term passive house refers to a specific construction standard for residential buildings with good comfort conditions during winter and summer, without traditional heating systems and without active cooling. Typically this includes very good insulation levels, very good airtightness of the building, whilst a good indoor air quality is guaranteed by a mechanical ventilation system with highly efficient heat recovery. Thereby the design heat load is limited to the load that can be transported by the minimum required ventilation air. However space heating does not have to be carried through the ventilation system.

For 40 - 60˚ Northern latitudes, under conditions specified in the PHPP calculation model: – the total energy demand for space heating and cooling is

limited to 15 kWh/m2.a treated floor area;

– the total primary energy use for all appliances, domestic hot water and space heating and cooling is limited to 120 kWh/m2.a


Specific final energy demand

Existing house: typically >250 kWh/m2.a

New construction: typically >150 kWh/m2.a

Low energy house: typically >100 kWh/m2.a

Passive house: typically <50 kWh/m2.a


Total cost of ownership (TCO)

TCO drops through minimising the investment in the heating system


How can heating be minimised?

A maximum, effective insulation

An excellent airtight construction

Rational use of the sun by intelligent glazing

Comfort ventilation with efficient heat exchange


Ventilation with heat recovery

Heat collecting windows

Airtightness

Thermal insulation


Insulation

Minimum heat transfer values (U). For example:


An airtight construction

For example:


Rational use of the sun

A right design for the size and position of windows

Intelligent glazing (e.g. triple pane glazing)

Limit the risk of overheating in summer, for example by:– Extra ventilation– Mechanical ventilation at night– A removable sun protection on the windows


Ventilation

The ventilation system with heat recovery is a crucial part of a passive house

The ventillation system should be controllable by the owners. It has to be adaptable according to the situation (guests, a party, cooking or not …)

Wet rooms (bathroom, kitchen…) need extra air extraction to avoid moisture


Heat recovery

A heat exchanger in the ventilation system recycles a large part of the heat. Efficiencies are typically 80% - 90%

Extra heating can be provided by a system of tubes in the ground that pre-heat the air coming from outside

The ground is warmer than the air in winter, but colder than the air in summer, so the same system can pre-cool the incoming air in summer

In some cases, an extra after heating by a solar boiler or a solar-gas boiler is provided


Combined with other energy efficient techniques

In most cases, the construction standards of a passive house are combined with:– High efficient domestic appliances– Efficient lighting– A solar water heater– Or a photo-voltaic system for generating

electricity

making a dwelling to a large extent independent from external energy sources


Also for renovation?

The passive house standard is mostly applied for new construction

In some cases, it can be applied during renovation

Making a passive house out of a standard house will often lead to a loss of space


Pioneering countries

Germany is the trendsetter in passive houses

In addition, passive houses have been built in Austria, Belgium, Luxemburg, the Netherlands, Northern Italy and Switzerland

In some countries, like Germany, Austria and Belgium, subsidies are granted for the construction of passive houses


Round-up

A passive house is a house with a minimum heating system but with good comfort conditions

This can be achieved by maximum insulation, an excellent air tightness, intelligent glazing and a ventilation system with heat recovery

Energy consumption is up to 85% lower compared to a standard house


Links

European Passive Houseshttp://www.europeanpassivehouses.org

International Linkshttp://www.igpassivhaus.at

in Belgiumhttp://www.passivehouse.be

in Germanyhttp://www.passivehouse.com

Business

Passive House