As a wise coach once said, “Even if you’re on the right track, if you’re not moving fast enough…you get hit from behind”. Our world has certainly sped up in our lifetimes, and the rate of change feels exponential. With change there are always consequences and part of consequences are unintended consequences.
As we have been regulated to build tighter and tighter buildings to save energy, we have created some interesting challenges as side effects. Houses that are this tight have had trouble breathing, and poor indoor air quality and mold are two side effects that are certainly unintended, but are very real issues just the same. Indoor air quality can be helped by properly engineering make-up air into the HVAC system and/or using air exchangers. Mold can be addressed with pretreatment of building components and by proper moisture control and proper building envelope planning and construction.
Who gave much thought to indoor air quality and mold thirty years ago? Back then was just the beginning of super insulated building envelopes and we hadn’t learned the lessons we now know today. The building code changes are by no means over and we will all be aiming at a moving target for years to come. Whether it’s the hurricane codes and how they change building or the energy codes and how they tighten up the building shell, it will continue to be up to us to anticipate and not simply react.
Doors and windows have evolved with the codes too. 30 years ago, a door or window wasn’t even rated for air or water infiltration. If they had been, they would have rated very low on today’s Design Pressure or Performance Grade scales. Whereas today, we see double hung windows rated with a DP70 rating, three decades ago you would have been lucky to see the equivalent of a DP 20. Doors and windows are made to much more exacting performance standards and frankly, as tight as houses are today, they have to be. As the only major operable part of the building envelope, doors and windows are subjected to incredible force with the differences in internal and external pressure. In the old days, a house could equalize easily. Remember those drafts we grew up with in older houses? The movement of that air allowed pressure and moisture to equalize easily between inside and out. Remember the old technique for surviving a hurricane? It was to crack open the windows on the leeward side of the house, to help equalize the tremendous storm pressure and not allow the house to literally vacuum water and air inside.
Windows and doors that are engineered to meet today’s higher demands and today’s higher standards will only perform to their rating, if they are installed as they were designed to be installed. To that end, the Building Code now requires that all windows and doors be installed in accordance with manufacturer’s installation instructions. Instructions from manufacturers are remarkably similar from company to company because the rating agency used to grade performance is the National Fenestration Rating Council (NFRC). So not only is it a code issue to not follow the manufacturer’s installation instructions, it’s also a potential warranty issue. In the event of a problem with a window or door, the last thing we want is to be debating with a manufacturer whether the problem is caused by installation.
If we do it right, we only have to do it once. We are happy to help with teaching your crews how to install windows and doors to factory specifications. For those who don’t enjoy reading multipage instructions in different languages, we have installation videos and jobsite training available so that your subs or employees know how to install to the letter of the law. We also offer pre-assembly of certain components such as slider frames and mulls in our shop to simplify the process on the job. Please check with your salesperson for details. Simply weigh the cost of one ounce of prevention against the always expensive pound of cure and remember one of our Shepley favorites, “We get what we inspect, not what we expect”. We’re here to help!