A new technical brief from SPRI, the trade association representing the manufacturers of single-ply roofing systems and related component materials, addresses construction-generated moisture and its impact on commercial roofing systems.
Construction-generated moisture comes from activities including pouring concrete, burning propane heaters, painting, plastering, and drywall finishing. These activities can contribute to excessive levels of relative humidity inside the structure when proper remediation measures are not taken. Accumulation of condensation within the roofing assembly and within the structure can result when the temperature is at or below the dew point.
To control moisture, designers must identify the sources of moisture and develop a remediation plan during the design process. To reduce the probability of condensation, buildings under construction must be adequately ventilated, particularly during concrete hydration and other high moisture-related construction activities.
SPRI recommendations include avoiding the use of wet materials or materials with excessive moisture, installing vapor retarders in the roof assembly, avoiding penetrating vapor barriers, installing at least two layers of insulation, and always sealing deck-to-wall joints and gaps around roof penetrations.
Related Stories
| Dec 20, 2012
China to build sustainable city for 180,000 from scratch
A 120-million sf urban development in China will be designed according to high green standards for about 180,000 residents.
| Dec 20, 2012
Air duct trade group urges maintenance, restoration professionals to avoid chemical cleaners
The National Air Duct Cleaners Association (NADCA) urges professionals to avoid using chemicals as a method for cleaning and maintaining air duct systems.
| Dec 20, 2012
Valencia College shifts from LEED to Green Globes on new project for more flexibility
The Lake Nona campus of Valencia College in Florida shifted its sustainability standard to Green Globes largely to be able to use a bipolar-ionization system to treat its indoor air -- something LEED didn't allow.
| Dec 20, 2012
LEED-certified schools don’t have to cost more to build, save average of 33% on energy
On average, green schools use 33% less energy and 32% less water than their conventional counterparts, and save $100,000 per year on direct operating costs, according to the U.S. Green Building Council.
| Dec 13, 2012
New OSHA initiatives on tap at AGC safety and health conference
More than 150 industry professionals will discuss the development of regulatory and legislative activity on national and local levels at the Associated General Contractors of America’s health and safety conference.
| Dec 13, 2012
So-called fiscal cliff is already affecting construction jobs, AGC finds
In November, the construction industry shed 20,000 jobs and its unemployment rate reached 12.2%, according to an analysis by the Associated General Contractors of America.
| Dec 13, 2012
New York City poised to enact recycling mandate for multi-family dwellings
New York City lags behind other large cities in recycling with only 15% of residential trash being recycled. A new bill passed by the City Council aims to improve the rate by changing how new apartment buildings are constructed.
| Dec 13, 2012
Pima County, Ariz. officials say improved code enforcement scores will help lower insurance bills
Insurance Service Office, Inc. (ISO) recently analyzed building codes and enforcement and found that Pima County, Ariz., consistently outscored comparable jurisdictions in Arizona and the nation.
| Dec 13, 2012
D.C. aims to be a green leader with new building codes
The District of Columbia has released a revised set of building codes to make it a leader in green construction.