---

---

---

---

Science Current Events and Science News RSS Feeds

---

---

Email a Friend Printer Friendly

The natural way to keep houses warm

January 05, 2004

Anyone who bought a new house built in Germany after 2002 has no worries. New building regulations introduced that year impose stricter energy standards, so these homes are generally well insulated. On the other hand, owners of older buildings should consider an energy-efficient renovation. The potential savings are significant. Statistically speaking, nearly 80 percent of domestic energy consumption is attributable to space heating, and older buildings require around four times as much energy to keep warm. Heating bills can be cut in half by adding insulation and replacing the furnace at the same time - a justifiable expense in the long run. Depending on fuel costs, the outlay can be amortized within a few years.

Builders and homeowners should also give thought to the type of insulation material used. Most people still opt for familiar standards such as mineral wool and rigid plastic foam, partly for cost reasons. But there is a wide variety of alternatives, including sheep's wool and compressed hay, or natural fiber mats made from hemp, flax, sisal or jute. "Insulation properties are not the only criterion," says Professor Klaus Sedlbauer, the new director of the Fraunhofer Institute for Building Physics IBP. "Other factors such as the material's ability to retain heat and moisture help to create the required degree of comfort. The material, its thickness and method of application should be adapted to the specific structural parameters."

The acceptance of insulation products made from renewable raw materials also depends on their price. The German Federal Ministry of Consumer Protection, Food and Agriculture has launched an incentive program which grants EUR 30 or 40 per cubic meter toward the purchase of insulation material, depending on its classification by the IBP. "The basic prerequisite is that it has a national or European building inspection approval," explains Norbert König. "The higher rate is reserved for materials that satisfy the conditions for a recognized quality seal."

The IBP has so far classified two dozen products from various manufacturers for inclusion in the list of materials that qualify for the state subsidy. The Fachagentur Nachwachsende Rohstoffe e.V., an agency set up by the ministry to coordinate renewable resources activities, manages the manufacturer and product database and stages presentations on the advantages and application limits of the various insulation materials. The conditions for qualifying for the subsidies and an application form can be found in German on the Internet.

Fraunhofer-Gesellschaft