A little moisture at a construction site can turn into a big problem. Not only does moisture cause project delays, it also invites the growth and spread of mold spores that can compromise a building’s structural integrity and the health of its occupants. To combat the persistently damp conditions during the winter, contractors look to construction drying solutions to stay on track, save costs and ensure that mold does not thrive within the building materials.
Mold Growth on Construction Sites
Mold spores are everywhere. They enter through building openings or attach themselves to clothes, shoes and construction materials. When a spore lands on a food source or a food source become wet, it creates an enzyme solution that uses moisture to dissolve the food, creating a nutrient-dense broth. This broth promotes germination and the formation of hyphae, root-like filaments coated with the same enzyme solution. In as little as 48 hours, hyphae can become thick, penetrate a material and form protective barrier, or mycelium, keeping a surface moist even if the air is dry. The mold then grows conidia, which produces and releases mold spores into the air.
When building materials are damp, it is not enough to maintain relative humidity levels at or below 60 percent. Such a situation requires the use of construction drying solutions that combine air movement and relative humidity levels of about 30 percent for several days. Because reactive measures can significantly delay a project, contractors experience the greatest success when they proactively prevent mold growth from the start using temporary climate control equipment.
Keeping Your Construction Site Mold-Free
- Identify and eliminate sources of moisture: If moisture persists in an area of a construction site, pinpoint its source as soon as possible. Sources can include HVAC leaks, pipes, roof leaks, old sprinkler systems and condensation.
- Material storage: Rather than allow building materials to be exposed to the elements, keep them in a dry storage facility or the manufacturing site until you need them. Then wrap and protect the materials before transporting them.
- Test moisture content: Before installing materials that mold could infiltrate, ensure their moisture content is within specification. Gypsum wallboards, for example, should have a moisture content of 0.4 percent or below on a gypsum moisture meter before you apply interior finishes on them. To reduce the risk of liability, test and document the moisture content of taped and sanded gypsum wallboards in two different locations: along the bottom edge and the halfway point between the floor and ceiling.
- Avoid using the HVAC system for construction drying: HVAC equipment is not designed to maintain ideal conditions at construction sites. Using heating and cooling systems for this purpose is unreliable, increases their load, wastes energy and might void their warranty. Construction drying solutions are a more effective and efficient choice, and have monitoring systems that ensure their reliability.
- Implement drying solutions to prevent moisture: Rather than try to remedy moisture problems, use temporary construction drying equipment to prevent them. When used for drywall mud, for example, you can achieve dry times of as little as 12 hours. The system prevents warping in millwork, wood framing and hardwoods. In addition, it promotes the proper drying and curing of concrete, adhesives, paint, surface coatings and other materials.
Polygon’s custom construction drying solutions—which include heaters, dehumidifiers and ventilation systems—give you full control of the environmental conditions on your site, eliminating the need to hope for good weather. Our advanced ExactAir® system allows you to monitor the environment and equipment throughout a project. Construction drying equipment not only helps you meet project deadlines, earn LEED credits and avoid unnecessary downtime, it also yields a significant cost savings per square foot. Talk to a specialist at Polygon today to learn more about how our solutions will keep your winter projects mold-free, cost-effective and predictable.
[Bon Adrien via CC License 2.0]