New Year’s Task: Building Envelope Check

By Charles C. Carpenter, CFM
From the November/December 2015 Issue

FENovDec15-FMFrequency-SLIDERIt is the time of year when many people start to create a holiday staple—the gingerbread house. These creations have come a long way from simply a kid-friendly activity. So much so, there is the 2015 National Gingerbread House Competition in Asheville, NC with pages of rules that remind one of the International Building Code. In 2013, Guinness World Records recognized the Texas A&M Traditions Club in Bryan, TX for building the largest gingerbread house on record. Measuring 60′ long and 42′ wide, the house was reported to have called for 2,500 pounds of candy treats to decorate its exterior.

An argument can be made that a good facility is like a champion gingerbread house in that the building envelope defines it. A superior building envelope keeps out a lot of things, most importantly water, while keeping in what you want.

Geography dictates the prevalent weather conditions that affect your facility most. You also have to look at natural disasters and how they may compromise your envelope.

Flooding is an ever-present cause for concern. You might not know FEMA makes the current floodplain maps available online for the entire United States. Facility owners may not be notified of changes in the floodplain since those notices are trigger by mortgages on the property, so they need to be proactive in monitoring revisions.

The building envelope starts with the foundation, and there are many factors that go into a good foundation. Buildings usually do not come with pre-formed foundations like a gingerbread house kit. Engineers help design solid foundations and include features to comply with seismic codes in earthquake-prone areas.

One instance in which a foundation might present an issue is with older buildings. Older buildings may have foundations of stone, brick, and mortar. And if a facility is located on the upper floors of a building, there is still reason for concern. You have to check for cracking and spawling in the concrete.

Above the foundation, a building envelope extends to the exterior walls. Walls can be made up of many materials, such as wood, brick, concrete, metal, and/or glass. Tilt-wall and pre-formed concrete remain popular exterior components, like a gingerbread house made of tilt-wall graham crackers. Thickness of the walls provide for strength and energy efficiency.

Walls and windows present a different set of concerns Sealants around windows and expansion joints breakdown over time. Walls at less 90° angles may allow water to seep in over time, requiring those surfaces to be periodically resealed. Facility staff should also be concerned about buildups around the walls. Erosion, dust, and debris raise the soil bed outside the walls or even the window seals.

Small penetrations let in water, while bigger ones provide entry to insects and rodents. The perimeter should be checked periodically to ensure the landscape has not shifted above the base floor elevation, as this could easily let water into the building. And nothing should be covering weep holes, since that could trap moisture in the walls and possibly lead to mold. Meanwhile, water and HVAC lines could be a highway for critters.

To top it all off, it’s crucial to examine roofing. Nothing does more to protect the building envelope. Roofing preferences vary by geography. Those in southern climates might prefer a reflective white PVC membrane, while those operating in northern climates might prefer a dark bitumen to absorb heat in the winter.

In colder climates, there are two issues to remember. The first is ice damming, which traps moisture on the roof and allows water to essentially flow uphill. The second is ice sheeting, where large pieces of ice breakaway from a sloped roof or even windows. Ice sheeting was on display during Super Bowl XLV, when ice sheets unexpectedly slid off the stadium roof in southern climate Dallas, TX.

Roofing is a “get what you pay for” proposition. Since few roofs can be covered in a single sheet of material, a good strategy is to look at materials that have the fewest field seams or welds as possible. A good material can easily be defeated by a subpar installation. Also, the thickness of the material is important, as it protects against dropped materials or hailstones. When inspecting a current roof or examining a new installation, consider common points of failure. Areas that often cause problems are flashings around the roof edge, expansion joints, and roof penetrations for things such as HVAC, skylights, or communication equipment.

A final option for reviewing the building envelope is thermal imaging. Using roofing contractors, consultants, or in house cameras, facility staff can examine the envelope for air leakage around windows, or water that has permeated the envelope but may have not made it inside. These cameras can be expensive but can be rented.

Meanwhile, don’t expect to find anyone making gingerbread facility managers. As you know, it is far from a cookie cutter proposition. Each facility presents different challenges, and the building envelope plays a large part. So, this new year prevent your facility from resembling a gingerbread house after the holidays—crumbling and picked over of all the good stuff.


Carpenter is site manager, global real estate for HP in Austin, TX. He has worked in facility management since 1995.

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