Technical Papers

Mold in Attic, Blandford, MA

Wednesday, September 14th, 2016 by Brendan Fogarty

A customer in Blandford, MA called us with some problems recurring in his attic in the wintertime.  He had significant ice damming every year and a severe problem with mold in the attic.  Leo contacted Dr. Energy Saver by Eco Energy Solutions to come and investigate the problem.

During the questionnaire process, Leo mentioned that he was running a dehumidifier in the winter in his attic. Further discussion brought up the fact that he was having a moisture problem in the attic, which was why he was using the dehumidifier.  Additionally, the temperatures in his home were very inconsistent throughout the year, especially in the winter.  After completing the questionnaire and building a strong accomplish list to address the problems in his home, we proceeded to do a thorough inspection.

During the inspection process in the attic, our Building Science Expert noticed and identified a significant amount of mold accumulating on the rafters and the underside of the roof deck.  Immediately, the Building Science Expert brought the homeowner into the attic to help him understand what was going on in his home.  Additionally, there was a minimal amount of fiberglass insulation in the gable vents and the rafter bays were blocked.  

The problem was there was no airflow allowing the roof deck to breathe which was causing a condensation problem due to warm air leaving the home.  This warm air, combined with the cold air in the attic, caused condensation which increased the amount of relative humidity causing mold spores to colonize.  Additionally, no air sealing of any of the top plates, electrical penetrations, plumbing penetrations or HVAC penetrations were sealed.  This allowed all the conditioned air to leave and new unconditioned air to come in from the bottom of the house.  This is called Stack Effect.  

Our resolution to this problem was a combination of a number of our treatments starting with removing all of the fiberglass insulation, including the gable vents, from the attic.  We then used our Mold Neutralizer killing the mold immediately on contact.  Then we air sealed all the penetrations and tops of the walls with our 1-Part Expandable Polyeuranem Foam and encapsulated all of the duct work where a significant amount of air was leaking.  We used our 2-Part Expandable Spray Foam to seal the ducts.  We properly ventilated the rafter bays with baffling devices.  Finally, we blew our TruSoft Cellulose insulation to a Department of Energy recommendation of R-60, which is about 18 to 20 inches.  An insulated catwalk was installed to allow all mechanical devices to be accessible.  

In the basement, where the unconditioned air was entering the bottom of the house, we airsealed the rim joist with our 2-Part Expandable Spray Foam.  The rim joist is the band joist which runs around the perimeter of the foundation.  We also installed an insulated basement door and brand new basement insert windows.

Finally, we dense packed the exterior walls from the outside using out TruSoft blown in cellulose.  This completed the entire enveloping of the home separating the conditioned spaces from the unconditioned spaces in this beautiful ranch home in Blandford, MA.  Not only did we reduce the cost of heating and cooling this home, we made this home comfortable year round.  To date, this homeowner has not had to run a dehumidifier in the attic in the winter and there is no sign of mold.