Exterior Water Damage

Water causes more damage in the United States than fire, and California has more water damage than any other state. Flooding and storm damage are considered to be sudden disasters and are often covered by insurance policies. On the other hand, water damage caused by dry rot occurs over a longer period of time and is not usually covered by insurance. Water damage to wood and masonry surfaces can often be avoided.


Wood Siding

T1-11 siding (the plywood siding with vertical grooves) often can be treated with elastomeric paint to prevent cracking, which leads to water intrusion and rotting. The elastomeric will bridge the cracks and remain flexible unlike regular latex paint that will crack. Masonite siding (or other man-made fiber board siding) is usually a lapped horizontal siding. Water damage occurs in two areas on this siding, the vertical joints and the bottom edge of the siding. Damage to the vertical joints can prevent by caulking whenever the joints open up. The bottom edge of the boards is usually very porous, which leads to water being absorbed up and damaging the boards. To prevent this it is important to “back brush” the paint which will work the paint into the bottom of the boards to seal the surface. Simply spray painting will not accomplish the sealing. Although back rolling the siding is better than simply spray painting, it will not do as adequate of a job as back brushing.

Wood Trim

window casings should be caulked on the top. The bottom of boards should not caulked but remain open for drainage to prevent water getting inside from being trapped.

Block and Stucco Masonry

Water damage to masonry usually appears in the form of efflorescence, caused when water enters the masonry. Upon leaving the surface of the wet masonry, the water leaches out some of the material in the masonry. The result will usually appear as a blistered, often powdery, white material.

Elastomeric Coatings

Elastomerics are commonly applied to masonry surfaces but are often they are overused. An elastomeric is a waterproofing material that forms a layer on a surface being painted similar to a coat of rubber . These coatings are designed to keep water out but, if not used correctly, they can also keep water in. Elastomerics should not be used on retaining walls that have earth behind the wall. The back side of such walls may not be properly sealed, resulting in water leaking through the wall. Typical latex paints allow a certain amount of water to pass through the paint; but elastomerics will not allow this to happen with the result that surface bubbles similar to water balloons can form on the wall. Elastomerics should be applied only to keep water from entering through small surface cracks. If a building has other defects, such as a block wall without a metal cap, that allow water can enter, then elastomerics should not be used.

Water Sources

For the concerns previously discussed water coming from above the structure is the source which is typically covered under insurance policies. However water damage is also caused from water coming from the ground. The cause for this type of damage is often considered by insurance companies to be flooding and thus is not covered unless you have flood insurance. Some common causes of such water damage are improper grading of surrounding grounds, earth piling up and touching wood so that moisture may enter. Many building codes require there to be at least six inches clearance between earth and siding or other wood components. Structures without gutters can result in splashing up of rain water, allowing wood to become wet and then rot.

Painting Specifications

An upcoming painting project is the opportune time to consider both the repair of past damages as well as protection of your property for future wear and tear. Specifications for a painting job should be specific to your individual project. All too often, details that are unique to the needed protection for a project. are omitted from specifications that the painting contractor will use. Having too many generalized specifications “just thrown in” can add to the cost of a painting project without adding to its value.

Paul McLaughlin is a principal at McLaughlin Painting, a new member of ECHO. He has been performing wood repairs, preparing specifications and painting for community associations for over thirty years.