Case Studies

Whether there is too much dust in your air or high humidity causing mold and musty smells, we can help you understand what’s going on and how to find a solution.  Like people, each home is unique and has its’ own quirks and characteristics.  Our experience along with your input will provide the way to a healthy and comfortable home environment.

The following project case studies will help describe the scope and breadth of our services.

Unfriendly Cellar:   

A client who had purchased a home noticed mold growing on furniture stored in their cellar as well as a musty smell when ever they were in the cellar.
 
Investigation:   The home is a sixty year old house nicely maintained and very clean with new paint and floor finishes on the inside.   The heating system is a gas fired forced hot water system.  There is no air conditioning.  Relative humidity readings showed  a 25% higher reading in the cellar than the upstairs.

Analysis:    High levels of moisture in the cellar ( above 75% R.H.) contributed to mold growth on stored items.  The mold growth produced mold by-products that accumulated and caused a distinct musty odor.

Recommendations:    Install an exhaust only fan in the cellar with vents from the upstairs providing make up air.   This flushes out the musty air and replaces it with fresh clean air from upstairs.  This will also tend to reduce the elevated levels of humidity in the cellar.

Results:     A Humidex exhaust fan was installed and within one hour the “musty” odors were gone.

Bowling Alley Disaster:   

A client with a bowling alley in his finished basement complained of a musty smell when ever the bowling alley was turned on.

Investigation:    The home is a two year old mansion style house with very sophisticated HVAC equipment and controls.  The musty odor occurred only when the bowling alley ball return system was on and could only be smelled when standing on the alley.   Removing the ball gutter allowed access to underneath the alley where puddles of water were found and mold growing on residual sawdust from construction.  Review of construction plans revealed an error in construction whereby the backyard patio adjacent to the bowling alley portion of the foundation was built higher than the top of the foundation.  This allowed wind driven rain to infiltrate over the top of the foundation and drain down the wall and under the bowling alley.

Recommendations:     Remove the bottom portion of siding where the driven rain entered over the foundation and provide an effective barrier to the entering water.   Remove the puddled water and moldy sawdust under the alley and clean all affected wood framing.

Results:   All recommendations were followed.  The water intrusion problem was eliminated and any existing mold was removed.  There have been no more odor or mold problems.

Condensating Window Scenario:   

A local representative for a national window manufacturer asked if we could investigate several instances where clients with new window installations were experiencing condensation on the interior of the window glass.

Investigation:     Each of the several homes with this condition was examined during cold weather when the moisture was actually present on the windows.    Relative humidity levels were recorded as well as interior surface temperatures of the windows and exterior walls.   In all cases elevated levels of moisture were found to be present in the range of 50% R.H. or higher.  At an interior air temperature of 70 degrees and relative humidity of 50%,  the dew point is about 52 degrees.   Most window surfaces colder than this in the winter, resulting in condensation.

Recommendations:    Find sources of excessive moisture in the house that contribute to elevated levels of humidity and remove or remedy them.   These sources can be unvented bath fans, dirt crawl spaces, water leaks and others.   Fixing these will lower the relative humidity level and stop the condensation on windows.

Results:  In all cases, moisture sources were discovered that were the causes for elevated relative humidity readings.  In each case, home owners were given specific direction on how to eliminate the problem.

LUMBER YARD WOES:   A local lumber yard was experiencing an unusual problem of mold growing on their wood trim and molding products which were stored under cover in an unheated storage area. 

Investigation:   The lumberyard storage area is a three sided structure such that exterior air freely infiltrates the area.    The location is in an area where fog is a frequent occurrence  and the lumber is subject to 100% relative humidity conditions.   On these occasions moisture will condense on the lumber and provide the right conditions for mold growth.

Recommendations:   Enclose the wood trim storage portion with a fourth wall, building it as tight as possible.  Pipe in a continuous supply of conditioned air from the adjacent office space.  This will produce a small a positive pressure condition in the storage shed,  keeping moist exterior air out and prevent mold growing conditions from occurring.   

Results:   A fourth side to the enclosure was built preventing a free flow of outside air to the lumber.  An in-line fan was installed to bring interior air to the enclosure and maintain a positive pressure  to prevent moist foggy air from entering.  Moisture no longer condenses on the lumber.

Safe House?   

A client who had lived in her house for more than ten years was concerned that her son who suffers from certain inflammation problems might be affected by poor air quality.

Investigation:  The home is a well maintained twenty year old two story house with a forced hot air heating system with same duct central air.   The HVAC system incorporated a  merv 6 air filter with an ultra violet bacteria control light.  Particulate measurements showed very low particle counts.  Relative humidity was 50% or lower.     Air quality appeared to be good.   An interview with the homeowner revealed a history of small water leaks in two bathrooms and in one exterior window.   Examination of these sites showed areas of residual mold growth which had not been removed or cleaned.

Analysis:   Mold growth contains a variety of contaminants even after it has dried and moisture is no longer present.  Disturbing these sites can cause a localized dispersal of mold products that can pollute the air in a room or portion of a house and become a health irritant.

Recommendations:   Remove and replace affected areas of sheetrock, trim or insulation where mold has grown and clean all adjacent areas.