Better than new buildings – best practices turn into national standard

Felicitas Kraus and Stefanie Grether, German Energy Agency (dena)

Keywords

CO2-emission reduction, existing buildings, renovation, action plan, residential buildings, non-residential buildings, passive-house-technologies in existing buildings, governmental promotion, regional networks, role-model-function, best practice

Abstract

Today an average existing residential building in Germany demands three times as much energy for space heating as a new building. Despite rising energy prices more than half of the economical energy saving potential stays untouched during refurbishment processes. Therefore dena supported by the Federal Ministry of Transport, Building and Urban Affairs initiated the project “Efficient Homes” (the German name of the project is “Niedrigenergiehaus im Bestand”). The strategy of implementing nationwide standards for existing residential buildings that are higher than the federal requirements for new buildings will be the focus of the paper.

The project relates to more than 143 existing buildings being refurbished since 2003, partly using highly innovative passive-house-technology. These buildings cover the whole spectrum of residential buildings from single family homes (containing one dwelling unit) as far as multi-family dwellings (containing 295 dwelling units). On average these renovated buildings demand more than 50 % less energy than federal minimum requirements for new buildings. The “Efficient Homes”-project objectives are:

Development and testing of innovative and cost-effective low-energy standards
Strategies for launching these standards and innovative techniques
Know-how-transfer to all stakeholders (e.g. building owners, architects)

The refurbishment projects and the transferable, economical renovation-recommendations have a role-model-function: 2003-2005 33 buildings, 2005-2006 another 110 buildings. To strengthen this effect, dena has created a successful network of regional competence-centres. The nationwide PR accelerates know-how-transfer and the launch of innovative technologies.

Further steps: in 2007 the standards of the “Efficient Homes”-project will be implemented in a nationwide federal promotion programme. This leads to about 500 additional buildings per year from 2007 onwards. dena will accompany introduction and further development of these standards. The “Efficient Homes”-project will be expanded from residential to non-residential buildings (starting with schools and kindergartens in 2007).