Hidden Dangers of Dryer Vents

Shirt and jeans in dryerWho would think venting a unit’s clothes dryer was so complicated?  When was the last time the cleanliness of dryer vents was on your Board’s meeting agenda?  Yet, clothes dryers may be one of the most dangerous appliances in the home.  The U.S. Consumer Product Safety Commission reports there are more than 15,000 home fires each year directly related to dryer maintenance and overheating with blocked exhaust venting contributing to half of those fires.  Dryer venting falls in the category of what you can’t see, can hurt you.

Just as condo units and their buildings come in many shapes and sizes, so does dryer vent systems.  It is not unusual for new Boards not only not understand the exact nature of their condo’s in-unit dryer vent system but they also are not certain who is responsible for its maintenance.  Most dryer vent ducts pass through common space, except for HOA unit owners who are responsible for their own building envelope and everything within.  Some condo dryer vent ducts are dedicated to a given unit while others are shared with other units.  Many dryers vent pass through an exterior wall while mid-rise and high-rise condo buildings share a vertical rooftop vent system.

With these different types of systems and variances often found in the governing condo documents, it is not always well understood by the Board members who is responsible for maintenance and repair of dryer duct systems.  This includes basic routine cleaning even if it is clear maintaining the in-unit dryer is part of the unit owner’s responsibility.  This is an important issue to resolve with the assistance of your legal counsel, as it is the first step in meeting the Board’s responsibility to oversee the safety of the units’ venting system and its occupants.

Once dryer vent system maintenance responsibilities are understood, a policy should be put in place.  This policy should provide authority for unit access and performing maintenance and repairs when owners fail to comply with the dryer policy including assessing charges to the unit owner incurred by the association in providing the required dryer maintenance.  The policy should specify the required maintenance including cleaning of the dryer vents and ducts on a scheduled basis, typically every two years.  Often communities will engage a dryer maintenance contractor at a bulk rate to provide a cost effective and consistent maintenance program.  Should a unit owner opt out of this service they would be required to provide proof of compliance of the required maintenance being conducted by others.

Before the dryer maintenance program can be implemented, the Board must understand their system.  This may require the assistance of a maintenance repair contractor or the association’s building engineer who will need to inspect the present system.  This inspection may reveal common and shared duct systems; long duct runs with booster in-line fans; improper duct materials.  As an example, any vent duct found to be vinyl, PVC, or flexible is a problem.  Most of these types of vent ducts are violations of the local and national building codes, as their interior surfaces collect lint creating a build up of highly flammable material as well as a medium to collect water whose weight can bend duct pipe and create an environment susceptible to mildew and mold.  Improper duct should be removed and replaced with smooth-walled metal ductwork.  If flexible duct is found forming an elbow at the rear of the dryer, it should be replaced with non-flexible metal elbow duct so as not to be crushed when the dryer is pushed against the wall.

The policy may set specifications on the type of dryers to be allowed in units.  Not all dryers are the same.  Beyond the differences between electric and gas-fired dryers, some dryers have significantly different exhaust characteristics.  Building codes recognizes this by allowing the manufacturer to specify the maximum length of straight vent duct to be used.  This typically can range from 15 to 90 feet.  This duct length is further defined by reducing the allowable length by 5 feet for every 90 degree bend and 2 ½ feet for every 45 degree bend in the duct.  For this reason, the policy should provide specific direction to unit owners of the minimum type of dryer performance allowed as well as advising the unit owner of the length of duct the dryer will be connected.  Some associations even place a placard at the duct wall connection with this information for future dryer installations.

In hiring the dryer maintenance contractor the Board should take the normal insurance precautions as when hiring any contractor, including coverage for general liability; automobile liability; workers compensation and umbrella liability coverage with key required endorsements.  These are needed to protect the association from both having to defend itself as well as pay damages as a result  of the contractor’s activities while also including additional insured endorsements; waiver of subrogation endorsement; and primary/non-contributory wording.

The contract with the maintenance contractor should specify the method of cleaning the dryer duct.  Typically the cleaning is a combination of extendable brushes and vacuum cleaning.  The scope of work should include specific clarification of disposal of duct debris both inside and outside the building.  Safety issues should be addressed, particularly regarding movement of gas-fired dryers.

The dryer maintenance policy can include some preventative maintenance guidance to unit owners.  Unit owners should be advised to report unusual dryer performance including longer than normal drying times or the dryer surface or clothes feeling hotter than normal.  The owners should also report their observations of the outside dryer louver vents not opening as much as before.  Excessive humid or burnt smells in the laundry area are all signs of blocked exhaust vent duct.  The recognition of dryer malfunctions and a good preventive maintenance policy will ensure the common safety for all.


Article written by Jack Carr, P.E., R.S., LEED AP, Criterium Engineers

Published in Condo Media, February, 2019

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