Passive Houses

What are passive houses?

Passive houses are characterised by their high energy efficiency, cost-effectiveness and environmental friendliness. According to the certification criteria of the Darmstadt Passive House Institute, a passive house is defined as a building with an annual space heating energy demand or heating energy consumption of no more than 15 kWh/m². In comparative terms, this represents a heating energy requirement of approx. 90% less than a house which does not conform to the Passive House Standard.

Instead of heating, energy sources from within the house are used: the body heat of the occupants, penetrating heat from the sun, but also heat that is generated while cooking or taking a shower – all these heat sources are used for internal heat production. The extremely low space heating energy consumption is achieved by means of energy efficient heat insulation and large, airtight windows.

Intelligent, modern ventilation systems ensure regular air changes using fresh air supply and heat recovery from the warm extracted air. The orientation of the house also contributes to achieving the Passive House Standard. For optimal sun penetration, a south-facing window of as large a size as possible should be installed, ensuring that it is not obscured by neighbouring buildings or trees.

Drensteinfurt passive house: Airtight window joints

The private new-build house in Drensteinfurt was intended to conform to the Passive House Standard. Passive solar energy generation was possible due to the south-facing orientation of the house. The house was built using a wooden frame construction – a further step towards a higher degree of sustainability in a residential home.


The design of the residential house includes a two-storey window unit. The optimal position of the house allows maximum penetration of sunlight and heat. In order to fulfil the Passive House Standard, the goal was to ensure the building envelope and window joints were as airtight as possible.


Terhalle, the building contractor which executed the project, used TP652 Compriband Trio Plus multifunctional sealing tape. The functionality and ease of installation of this product have found favour over the many years it has been in use. The sealing tape's three-dimensional corners produce clean joints which cannot be achieved using membranes. The blower door test was also positive:the result was an air change rate of 0.54. This is ideal for classification as a passive house!

Johanneshaus in Ulm:Passive House Standard for the church hall

A four-storey new construction was to replace the dilapidated old church buildings. The aim for the construction of the new church centre was to achieve as high a level of sustainability and energy efficiency as possible. The new Johanneshaus building was intended to house the church hall and the administrative offices of the church centre. The build was partly financed by donations.


As a result of the thick heat insulation, the windows were positioned in front of the walls. This meant that the building achieved a good isothermal curve and an optimal heat transfer coefficient (U-value). An airtight solution was required for a clean joint with the facing shell.


The illbruck Projecting Window Installation System was used to install the windows. In total, six components ensured a technically correct, airtight window seal. An additional advantage of the Projecting Window Installation System is the windows' maximum acoustic protection level. Using this modern system, it was possible to achieve the reference value of 43dB. The ift Rosenheim (Rosenheim Institute for Window Technology) conducted the inspection, which was successful. The new construction of the Ulm Johanneshaus now stands out not only for its attractive exterior in the style of the adjoining church, but also for its energy efficient, soundproofed church hall which meets the Passive House Standards.

Passive house standards with tremco illbruck

Passive houses are considered to be a pioneering building type within the energy-efficient construction sector. tremco illbruck provides system solutions which have been developed for use in passive houses and which offer the ideal combination of quality, durability and promotion of energy efficiency. Do you have any questions about using our products or do you require further information about passive houses and energy efficiency? Our experts will be able to offer further assistance.