Facility Management: The Building Envelope

water infiltration

This is a quick introductory post about the building envelope. One of the primary functions of any building is to keep out the elements, particularly moisture. The building envelope refers to the systems and materials that are designed to make a building almost airtight. There are many reasons why a well-designed building should want to have a strong seal against the elements.

Structural Integrity

Structural integrity refers to the ability of the construction materials to perform the work for which they were designed. For example, steel trusses are meant to carry a load that spans over a certain distance. If the truss is cut or damaged, its ability to carry that load is compromised, which could lead to disastrous consequences. Water penetration can begin the process of oxidation on steel components, which can weaken them significantly over time. Commercial buildings rely on steel for roof decks, load bearing trusses, columns, and rebar inside concrete. Preventing water infiltration into a building is extremely important in extending the longevity of a building.

Water can also cause problems on mechanical systems that are necessary for the proper function of a building. For example, a leak on your HVAC or electrical panel can cause serious problems that would interrupt the work of occupants of the building.


Water penetration due to a compromised building envelope has health consequences as well. Moist areas will often develop mold or develop some degree of degradation from the presence of bacteria. Water is essential for mold and bacteria to grow. These problems can be remediated. However, pockets of undiscovered moisture can often result in allergies and other illnesses for occupants.

Another way that this can manifest is by allowing too much humidity into a building. Buildings typically must maintain a 50% relative humidity for the comfort and health of occupants. Too high a humidity due to air leaks in the building envelope can result in mold growth in air conditioning ducts where the moisture condenses. Too low a humidity can result in respiratory discomfort for occupants.


Water infiltration can also cause havoc on maintaining the aesthetics of a building. Water infiltration can warp walls or blister paint. Roof leaks can stain suspended ceiling tiles. Water infiltration from below can result in loose floor tiles, warped wooden floors, or stained carpets. Condensation can also form within double-pane windows when water infiltrates that space. Water infiltration can damage asphalt, causing potholes and uneven areas.

A well-designed building will have systems and materials included in the construction to keep out the elements, thus providing a controlled environment in the interior. By controlling the interior environment, facilities are able to maximize the comfort of occupants while minimizing the amount of maintenance necessary to remediate problems caused by water and air infiltration. Thus, maintaining the building envelope is one of the primary responsibilities of a Facility Manager. This requires some understanding of the engineering requirements of the building envelope, as well as the financial foresight to tackle building envelope problems before they grow larger and more expensive.

I'll be back soon with more information on building systems, building maintenance, and the management of these. There are industry practices that you can put into practice with your own properties, including your home. See you soon!

The content in this post is all original and a part of my day to day work.