Water Damage and Where it Starts

“Water, water everywhere,” is not what you want to be thinking as you’re standing in the living room of a townhouse condominium unit or peering into the lobby of a high-rise. Water inside any attached housing structure means likely damage – furnishings and fixtures, floors and walls; it also means the possibility of rotting wood and mold risks; it means potential liability, and that something has gone terribly wrong.

When property managers and board members worry about weather-related water damage, they are usually thinking about the damage caused by flooding at the bottom of a building, or by a leaky roof at the top. But engineers think in terms of “water intrusion,” which may result from a flood or a leaky roof, but is more likely caused by construction flaws in a building’s envelope – the components that separate the interior from the exterior. Flooding is an act of nature. The conditions that permit water intrusion are man-made. Windows and doors sliding, balconies and surface “transitions” are particularly problematic.

Windows and Siding

It is not the type of windows or siding you select that matters most; it’s how well they are installed. A low-quality product installed correctly can be perfectly water-tight; the best quality product installed poorly will imitate a sieve. One of the most common installation mistakes is the incorrect laying of building envelope materials, such as the house wrap, the flashing, or the siding itself. When this occurs, water isn’t shed properly from one material to another; it accumulates behind the materials and penetrates the structure. Incompatible materials in the building envelope can also permit water intrusion by creating temperature variations that can cause sealants to fail. Failing to recognize how different products perform is another common problem. Brick veneer can certainly look quite nice on buildings but brick isn’t watertight, and if the contractor fails to install “weep holes” through the veneer, the water will not drain properly. If water accumulates behind the veneer, there is a good possibility for mold to form.

Balconies

Outdoor balconies are a common feature. Many balconies are on the same level as the living room floor due to an accessibility requirement, to permit ease of access for someone in a wheelchair. But in a heavy storm, wind-driven rain may be forced under the door sill and into the living room. Some balconies have walls on all sides. A system of drains and pipes conducts water to the ground when it rains. These same pipes may possibly freeze in the winter causing the water to accumulate on the balcony and then flood the attached living rooms.

Cool Designs

Varying materials, using different shapes, and inserting angles all add architectural interest to a building; but every angle you create, every transition you make from one shape or material to another creates a point at which water may intrude. Transition or termination points represent a tiny portion of a building’s envelope, but they account for much of its vulnerability to water. And they don’t always receive the extra water-proofing they require.

 From the Inside Out

While many water intrusion problems result from something builders fail to do, some are caused by what builders, or the subcontractors working for them, do. Consider the plumbers, electricians, and HVAC mechanics who come into a building that has been framed, wrapped, and made water-tight and poke holes through that nice, water-tight surface. The wall penetrations are necessary to make connections that run from the inside out, but they also have to be properly waterproofed, and they often are not. That’s why the small details that can create immense water intrusion risks are so often overlooked.

Controlling the Risks

Water intrusion is a potential risk that the boards and managers of communities can reduce by being mindful, diligent, and proactive.

1. Don’t ignore early signs of water intrusion.
2. Bring in experts at the outset.
3. Don’t assume water intrusion in one unit is an isolated problem.
4. Take care of preventive maintenance.
5. Consider flooding risks.
6. Don’t look for shortcuts.

If the problem is systemic, you will have to deal with it systemically. There are no Band-Aids for water intrusion. If transitions on the building’s surface weren’t set properly, you have to re-do them. If the windows weren’t installed properly, you may not have to replace them, but you will have to re-install them. These measures are going to be expensive. But they will be far less expensive than dealing with the damage water intrusion can do to buildings, to the personal property, health of residents, and to the finances of your condominium. 

Reach out to your condominium board, property manager, or engineer today if you have any questions, or need further guidance on handling water intrusion and potential damage.

Henry J. Jansen, P.Eng., ACCI – President
www.criterium-jansen.com