Wrong. If zero-energy-building or passive-house components are used, heating energy requirement can be reduced much further.

Right!

Wrong. If zero-energy-building or passive-house technology is used, much better values can be achieved.

Wrong. However, by means of energy-efficient renovation heating costs are significantly reduced, and it won’t be necessary to renovate again after a short period of time.

Wrong. By means of energy-efficient renovation energy consumption is reduced by 90 percent, down to a tenth.

Right. With this significant reduction, the renovation measures are sustainable for many decades.

Wrong. Not only transmission heat loss, but also ventilation heat loss is minimized.

Wrong. Not only ventilation heat loss, but also transmission heat loss is minimized.

Right!

Wrong. The building services should be renovated before the building envelope only if the envelope will last for another 15 to 20 years.

Right. First the building envelope should be renovated, then the building services can be renovated to fit in with this.

Right. This guarantees optimum air change rates. In passive houses, space heating can be provided through the ventilation system, too.

Wrong. Airing the rooms manually does not result in optimum air change rates. A controlled ventilation system with heat recovery should be installed.

Wrong. While this still provides good indoor air quality, it lacks heat recovery, which is essential for energy-efficient renovation.