Staying healthy in a tight house

Accord­ing to the Ger­man Energy Sav­ing Ordin­ance (EnEv), good thermal insu­la­tion is man­dat­ory for new build­ings. But also when ret­ro­fit­ting energy-effi­­cient equip­ment or when renov­at­ing exist­ing build­ings, it is neces­sary to ful­fill cer­tain energy require­ments. This bene­fits our envir­on­ment and is good for your wal­let. But does­n’t the heat also keep humid­ity and pol­lut­ants in the house? Read here which pre­cau­tions should be taken.

1. Providing a leak-tight seal

Build­ings con­sume almost 40 per­cent of total energy in Ger­many. Up to 85 per­cent of this energy “goes up the chim­ney”. Com­mon causes are unin­su­lated exter­i­or walls and leaks in the build­ing envel­ope. These prob­lems can be remedied, for example with the help of an extern­al thermal insu­la­tion com­pos­ite sys­tem (ETICS). It con­sists of pre­fab­ric­ated com­pon­ents that are installed on the facade. Rigid poly­styrene foam and min­er­al wool are the insu­la­tion mater­i­als of choice. The lat­ter is also well suited for insu­lat­ing the roof. The win­dows should be equipped with double or triple glaz­ing and insu­lated pro­files. Repla­cing the old win­dow gas­kets by new ones made of plastic or sil­ic­one can already work won­ders. Exposed heat­ing pipes can be covered with insu­lat­ing ele­ments from the DIY store and gaps under­neath doors can be sealed with door brush strips. As a res­ult, res­id­ents save heat­ing costs, com­ply with leg­al require­ments and pro­tect the cli­mate.

2. Proper heating and ventilation

Many build­ers and ren­ov­at­ors fear that liv­ing in a well-insu­lated house will be like liv­ing in a “plastic bag”. The walls can no longer “breathe”, they believe. But with a few tricks, the exchange of air will not be affected. It can even be clev­erly con­trolled instead of driv­ing energy costs up. Reg­u­lar (purge) vent­il­a­tion is essen­tial: with the win­dows wide open, air the house briefly but intensely. Altern­at­ively, a reg­u­lar flow of fresh air can be provided by suit­able vent­il­a­tion sys­tems. This allows mois­ture to escape – mois­ture that is pro­duced in every house­hold by breath­ing, sweat­ing, cook­ing, shower­ing and clean­ing. The com­bin­a­tion of prop­er vent­il­a­tion and heat­ing (always leave the heat­ing to run at low tem­per­at­ure in winter) removes the breed­ing ground for mold.