Risks of Designing Buildings with Poor Indoor Air Quality

On aver­age, Amer­i­cans spend over 21 hours per day inside of build­ings. The most vul­ner­a­ble, infants and elder­ly, spend even more time indoors. For most Amer­i­cans, expo­sure to tox­ic air pol­lu­tants is dom­i­nat­ed by what we breathe indoors, rather than what we are exposed to out­doors. These health risks dwarf all oth­er envi­ron­men­tal expo­sures the typ­i­cal per­son will be sub­ject­ed to.

For that rea­son, rea­son­able changes in build­ing design and oper­a­tion must be made in order to improve indoor envi­ron­men­tal qual­i­ty. The social cost due to poor health is con­sid­er­able. The eco­nom­ic cost in terms of work­er pro­duc­tiv­i­ty in the Unit­ed States alone is esti­mat­ed to be on the order of tens of bil­lions of dol­lars annu­al­ly. In fact, stud­ies have shown that improved indoor air qual­i­ty can raise work­er pro­duc­tiv­i­ty and even raise the test scores of school chil­dren.

A Shift to Indoor Air Quality Research

Despite know­ing the impor­tance of indoor air qual­i­ty, the major­i­ty of research and fund­ing today con­tin­ues to be focused on out­door air qual­i­ty issues. There are more laws and reg­u­la­tions of prod­ucts and process­es that effect out­door air qual­i­ty than there are for indoor air qual­i­ty. Research into the impacts of build­ing mate­ri­als, fur­ni­ture, chem­i­cals, and oth­er prod­ucts on human health are still rel­a­tive­ly new but gain­ing seri­ous atten­tion in aca­d­e­m­ic cir­cles.

The Build­ing Ener­gy and Envi­ron­ments Pro­gram at the Uni­ver­si­ty of Texas in Austin is lead­ing the way in indoor air qual­i­ty research and is mak­ing sig­nif­i­cant and some­times unex­pect­ed dis­cov­er­ies year in and year out. Led by Dr. Richard Cor­si, the pro­gram and the University’s Indoor Air Qual­i­ty Lab are paving the way to under­stand­ing what is in the indoor air we breathe and the impacts on our health and well­be­ing.

Ear­li­er this sum­mer, we were treat­ed by Dr. Cor­si to a tour of the IAQ Lab on the J. J. Pick­le Research Cam­pus in Austin, Texas, where fac­ul­ty and stu­dents con­duct micro (small test cham­ber) and macro (full size home) lab­o­ra­to­ry test­ing of indoor air. The lab tour and pre­sen­ta­tion was one of the high­lights of the 2017 Austin Sus­tain­able Build­ing Mate­r­i­al Forum, a gath­er­ing of thought lead­ers in the man­u­fac­ture, spec­i­fi­ca­tion, and instal­la­tion of build­ing mate­ri­als. What we learned on this brief tour was noth­ing short of sur­pris­ing.

Are We Doing More Harm Than Good?

As the con­struc­tion indus­try con­tin­ues to push for the green­est and most sus­tain­able build­ing mate­ri­als, indoor air qual­i­ty has become sig­nif­i­cant­ly more impor­tant. The indus­try has suc­cess­ful­ly reduced or elim­i­nate VOC’s (volatile organ­ic com­pounds) from indoor mate­ri­als and fin­ish­es in response to the known effects of these pol­lu­tants on human health. While the push to rid our build­ing of VOC’s has been pos­i­tive, there have been some unin­tend­ed results.

When poli­cies man­date change, we often don’t imme­di­ate­ly rec­og­nize or real­ize the impacts. What the researchers at the IAQ Lab have dis­cov­ered is that man­u­fac­tur­ers of the glues and paints used in build­ings have sig­nif­i­cant­ly reduced VOC’s, but are now using SVOC’s (semi-volatile organ­ic com­pounds) in order to main­tain the material’s effec­tive­ness. While man­u­fac­tures are able to claim 0% VOC con­tent for their new sus­tain­able” prod­ucts, SVOCs may not be any bet­ter in the long-run.

Semi-volatile organ­ic com­pounds are a sub­group of VOC’s that tend to have a high­er mol­e­c­u­lar weight and high­er boil­ing point tem­per­a­ture than VOC’s. SVOC’s are of con­cern because of their abun­dance in the indoor envi­ron­ment and their poten­tial for neg­a­tive health effects on humans. SVOC’s are found in car­pets, tex­tiles, fur­ni­ture, mat­tress­es, paints, aerosols, per­son­al hygiene prod­ucts, clean­ing prod­ucts, and flame-retar­dants to name a few. The health effects from expo­sure to SVOC’s vary depend­ing on the par­tic­u­lar SVOC, the length of expo­sure, and per­son­al sen­si­tiv­i­ty. SVOC’s have been asso­ci­at­ed with aller­gies, asth­ma, endocrine and thy­roid dis­rup­tion, repro­duc­tive tox­i­c­i­ty, and fetal and child devel­op­ment delays.

How Heat and Humidity Makes Things Worse

Anoth­er inter­est­ing research top­ic being stud­ied at the IAQ Lab is the effects of rel­a­tive humid­i­ty (RH) and tem­per­a­ture on chem­i­cals stored in the sur­faces of mate­ri­als inside build­ings. Chem­i­cals we bring indoors with us, clean­ing prod­ucts and house­hold items we use every day, and build­ing mate­ri­als like car­pet glue, paint, and numer­ous oth­er prod­ucts are all sources of poten­tial­ly tox­ic pol­lu­tants. The lab dis­cov­ered that as indoor humid­i­ty increased in a build­ing, the water mol­e­cules in the air are adsorbed (adhe­sion of mol­e­cules of gas, liq­uid, or dis­solved solids to a sur­face) onto the var­i­ous mate­ri­als in the build­ing, there­by dis­plac­ing chem­i­cals already adsorbed to the mate­r­i­al and releas­ing them into the air. They also found that as the tem­per­a­ture in a build­ing rose, there was an increased rate of release of chem­i­cals into the air.

The tour was eye open­ing and led to many ques­tions for Dr. Cor­si and the researchers at the IAQ Lab. As build­ings are being bom­bard­ed with high­er heat and humid­i­ty in the sum­mer what is being released into the indoor air we breathe? As the archi­tec­ture and con­struc­tion indus­tries con­tin­ue to push for more sus­tain­able build­ing prac­tices, we need to be more knowl­edge­able of the dri­vers of indoor air qual­i­ty for the build­ings we are design­ing and con­struct­ing.

Improving Indoor Air Quality

For starters, design­ers should be spec­i­fy­ing mate­ri­als with no VOC’s and no SVOC’s. Using few­er adsorp­tive mate­ri­als will help reduce the trap­ping and stor­age of poten­tial­ly dan­ger­ous chem­i­cals and pol­lu­tants that can con­tribute to long term health effects. A ther­mal­ly effi­cient wall sys­tem with a high per­form­ing air bar­ri­er and well-designed HVAC sys­tem can also help by keep­ing the humid­i­ty and tem­per­a­ture well-reg­u­lat­ed, keep­ing out­door pol­lu­tants out, and effec­tive­ly fil­ter­ing indoor pol­lu­tants before they cause prob­lems.

Build­ings need to be built bet­ter with a spe­cif­ic focus on the indoor air qual­i­ty for the occu­pants. The Bau­tex Wall Sys­tem™ gives archi­tects a ther­mal­ly effi­cient and air tight build­ing enve­lope option for com­mer­cial and res­i­den­tial con­struc­tion. Bau­tex Inte­ri­or Wall Fin­ish (IWF) is a direct-applied abuse-resis­tant plas­ter that can be applied to the Bau­tex Wall Sys­tem as well as con­ven­tion­al­ly framed inte­ri­or walls. The IWF fin­ish pro­vides a 0%VOC and 0%SVOC hard­ened sur­face that pro­vides a health­i­er, stronger, and eas­i­er to main­tain fin­ish com­pared to con­ven­tion­al dry­wall and paint.

For more infor­ma­tion about indoor air qual­i­ty and the Bau­tex Wall Sys­tem, vis­it bau​texsys​tems​.com