Published in the ECHO Journal, April 2011
A Guide to Sleuthing
Winter is passed; now it’s time to get out and perform your first bi-yearly maintenance inspection. Early inspections will reveal how winter conditions have impacted the components of your building’s exterior envelope. Then later on, your fall inspection will reveal how the intensity of longer sun exposure and greater daily temperature fluctuations affected these same components. Diligent twice a year inspections allow you to stay ahead of the curve by gathering additional information and being proactive and knowledgeable in planning your maintenance “To Do” list.
In the course of general maintenance, one is occasionally confronted with solving the mysteries of isolated building component failure. These areas can simply be the result of “higher exposure” to the elements. An increased frequency of general maintenance procedures are generally adequate to solve these issues. Sometimes the problems go deeper and are caused by poor design and/or poor construction, requiring more extensive intervention.
As a sleuth, equip yourself with a notepad, binoculars, a moisture meter and a camera to document what you find. Photos are an unparalleled way to capture the passage of time and monitor how quickly an issue is evolving. Binoculars allow you to see details missed by an eye scanning from a distance. Slow your scanning down. Some signs or symptoms of deterioration are hard to spot by an “untrained” eye. Have patience. By slowing down and focusing on the details, you get to know and understand your building. Each inspection will add cumulatively to your knowledge base.
A moisture meter is another important sleuth’s tool. Elevated moisture levels in any material are the first sign of problems ahead. A moisture meter can allow you to pinpoint a water intrusion source or define the boundaries of a problem. Remember, “An ounce of prevention is worth a pound of cure.” So, slow down, focus and get to know your building. Think Sherlock Holmes. Such attention will pay off hugely in preserving the value of your asset and give you the personal satisfaction of solving the mystery puzzle.
Remember, each building is a unique blend of building materials situated in its own environmental niche. Each material reacts differently when it is exposed to varying degrees of sun, shade, wind and rain, as well as its interaction with other building envelope components. When this is overlaid with poor waterproofing design details, poor choice of existing materials and/or substandard construction coupled with building age, a complex puzzle is waiting to be solved.
The first rule in maintenance sleuthing is to be consistent and systematic in your approach.
Create a checklist that is specific to your building. Solicit the advice of some trained experts (i.e. architect, engineer, general contractor, paint representative, roofer) to glean pertinent information to educate yourself on your building. Apply this knowledge with a watchful eye; you want to address the following areas:
- Site drainage and hardscapes;
- Landscaping and trees;
- Stairs and decks;
- The wall system including windows and doors;
- The roof system.
The following paragraphs offer some general “best practice” sleuthing guidelines to help you formulate the backbone of your exterior maintenance checklist.
Your building rests on concrete foundations. Any vertical displacement or shifting movements will telegraph into the structure, possibly influencing how windows and doors open or close, how decks or roofs drain and how siding handles the movement by cracking, warping or buckling. Damage may also be seen on the interior finishes.
What can cause foundation movement? Soils, especially those with high clay composition, will expand and shrink according to moisture content. General soil moisture content is directly influenced by controlling the drainage flow of water off and around the building (unless you have an underground spring). All water needs to drain away from the building. Make sure water from roof downspouts is directed well away from the foundations, preferably into a contained storm sewer system. Look at your landscaping. Mature trees can lift foundations, crack them and plug up perimeter subsurface drainage systems. Growing roots can also raise the soil level around the tree or shrub, which may eventually cause a reverse slope back toward the foundations and block drainage flow patterns. Water ponding or slow draining around the foundation perimeter may allow water to seep below the foundations and rise into crawl spaces, thereby increasing interior moisture levels that may cause floors to buckle or foster mold growth. This is not a healthy situation. There should never be standing water in a crawl space.
It’s also not a good idea to let vegetation grow tight against the building. This situation restricts airflow; thus your siding stays moist without drying out, and the paint surfaces can become moldy. The plants also tend to abrade the paint finish during windy conditions and may conceal termite tubes leading from the soil up into the building.
As a general rule, maintain at least 6 inches clearance between the soil and the bottom of the siding. Don’t let planter mulch build up too high. Siding is usually installed to overlap an inch or so below the actual wood structural framing of your building. If soil or mulch touches or covers the bottom edge of siding, water can wick up into the framing, causing wood rot, and again termite tubes can be concealed.
Decks and stairs create horizontal surfaces adjacent to the building’s wall system. Horizontal solid surfaces accumulate rainwater, which must then be controlled and directed away from the building. Always look under decks and stairs for signs of water leakage—stain marks, mold or rust streaks from bolt attachments. These are warning signals that deeper issues need to be solved. Use your moisture meter to test moisture levels of materials, especially if the areas are supposed to be dry. Any cellulose material with moisture content greater than 20 percent becomes very susceptible to rot and mold.
With your binoculars, slowly scan the elevations of your building. What you are looking for are protruding nails (which will actually funnel rain water into your building), any stains or discoloration coming from cracks (signs of possible dry rot), buckled or warped siding (water is getting in behind the siding at some point above these areas), trim that is puckered, cracked or shrunken dimensionally (sure signs of wood rot) and the overall condition of the paint surface. Look for peeling, blisters, open caulk joints or a chalky surface (paint will rub off onto your fingers) that indicates a paint job is needed. Remember, paint will weather differently on different elevations depending on exposure to the elements. This may ultimately require separate painting schedules for different elevations.
There is no standard rule for when to repaint a building. A “well-prepared” paint job should last between 5 and 12 years. Why such a wide variance? A paint job is only as good as the substrate’s preparation and stability. Paint is a thin film with a finite ability to span cracks. It needs a clean, dust-free, non-peeling surface to adhere to. Substrate stability reflects a material’s expansion and contraction coefficient and its moisture content. For instance, stucco is cementatious and much more stable than wood siding, even when wet. A paint job will generally last longer on stucco than on wood. When wood siding expands and contracts during diurnal temperature fluctuations, caulk joints are stressed, eventually fail and water enters in behind the siding. This infiltrated water is absorbed by the wood siding, causing it to expand, crack, buckle, decay or force the paint to debond from the substrate (peeling or blisters). This is why wood-sided buildings need more TLC and a more intensive maintenance program to continue performing well over time. Therefore, when a building needs to be repainted is strictly driven by the material substrate, the surface preparation prior to painting, a quality detailed caulking job and the building’s exposure to the elements—not to a standard length of time.
When checking out your roof system, remember that the roof’s waterproofing integrity is a function of the condition of the roof membrane and the essential integration of metal flashings at transitions. As a system, when these parts are correctly melded together, your roof system will function in a superior fashion, keeping you dry and protecting the other building envelope components. Environmental exposure, age and lack of periodic maintenance all lead to different rates of roof system deterioration.
Roofs, as a horizontal surface, are meant to stop water from entering a building and direct it to specific drainage points. Always make sure the path of flow and exit points are unobstructed by leaf litter, tennis balls, new skylights and the like. Ponding water tends to accelerate roof material deterioration; check for tell-tale evaporation ring stains. Blisters, caused by expanding water vapor, are generally a sign that water has gotten between roofing layers. When these faults are coupled with surface cracks, alligatoring of the surface asphalt, bare patches that allow exposure to UV’s deteriorating rays, cracks between the metal flashings and the roof material or ceiling stains at top floor rooms, it is time to call a good roofer. Roofs don’t last forever, but periodic maintenance and tune-ups will definitely extend a roof’s service life.
Sleuthing creates a spin from simply performing routine generalized maintenance to having fun solving and unraveling the intricacies of how to achieve sustainable long-term performance from all your building envelope components. The reward of that job well done is less crisis maintenance and the associated high costs of unexpected unplanned repairs to a more controlled flow of maintenance dollars.
Superior sleuthing keeps money in your pocket till you are ready to spend it! Get your sleuthing tools together and move into your first maintenance inspection of this year. Good luck!
Steven Saarman is a principal at Saarman Construction, San Francisco, CA. The firm is a member of ECHO. He is a frequent ECHO seminar speaker and contributor to the ECHO Journal.