Bad air? Not inside our homes!

Giv­en the amount of time people spend indoors, it is all the more import­ant that our liv­ing space is sup­plied with suf­fi­cient amounts of fresh air. Reg­u­lar vent­il­a­tion of the rooms and a care­ful choice of build­ing mater­i­als ensure a healthy liv­ing envir­on­ment.

Spring is in the air. When everything in nature is start­ing to blos­som and bloom, we are drawn out­side to take a deep breath of fresh spring air. How­ever, unlike pre­vi­ous gen­er­a­tions, people today spend much more time indoors – on aver­age 90 per cent of their time, accord­ing to a sur­vey in 14 coun­tries com­mis­sioned by the com­pany Velux a few years ago. The increased amount of time work­ing from home, being the res­ult of the coronavir­us pan­dem­ic, has fur­ther fueled this trend. No mat­ter how cozy your home may seem, the air and humid­ity con­di­tions inside the rooms are very dif­fer­ent to those out­side.

There are a mul­ti­tude of factors determ­in­ing the indoor cli­mate. Start­ing with the build­ing envel­ope: Depend­ing on the qual­ity of its insu­la­tion, it may be abso­lutely windtight or have drafty spots. In the worst case, both can ulti­mately lead to mold growth. Adequate vent­il­a­tion of the rooms is there­fore of cru­cial import­ance. The nor­mal activ­it­ies of every­day life such as cook­ing, shower­ing and dry­ing laun­dry load the indoor air with mois­ture, odors and emis­sions. Dur­ing sleep, the aver­age per­son needs around 280 to 300 liters of air per hour, while a full-power workout on the exer­cise bike may increase air con­sump­tion to 3600 to 4000 liters. This is why we need fresh air! In any case, it is essen­tial to com­pletely replace the air inside the room sev­er­al times a day. Oth­er­wise, the CO₂ con­tent will reach an alarm­ing level and may cause head­aches, con­cen­tra­tion prob­lems, tired­ness and poor sleep. When adding the emis­sions from cigar­ettes, burn­ing candles, build­ing mater­i­als, fur­niture sur­faces and clean­ing agents, it is obvi­ous that there is an increased risk of devel­op­ing asthma or aller­gies over time.

Reg­u­lar and thor­ough air­ing of the rooms also helps to keep the air humid­ity inside our homes at a health-com­pat­ible level. On the one hand, people pro­duce and release a lot of mois­ture to the room dur­ing their nor­mal activ­it­ies. But dur­ing the heat­ing peri­od in the cold sea­son, the air can also be too dry in some areas, which may irrit­ate the res­pir­at­ory tract. This is why heat­ing is so import­ant in addi­tion to vent­il­a­tion: Warm air can absorb much more mois­ture than cold air. In addi­tion, overly eco­nom­ic­al heat­ing pro­motes the devel­op­ment of cold wall sur­faces with the res­ult­ing risk of mold growth.