Regarding our education/certification, here is a little explanation from the Chimney Safety Institute of America website www.csia.org:
The CSIA Certified Dryer Exhaust Technician® (CDET) program is a comprehensive, written, examination that is administered, and graded by the Chimney Safety Institute of America. The examination evaluates a Dryer Exhaust Technician's understanding of the basic information technicians must master to become competent dryer exhaust safety and fire prevention specialists. Technicians desiring to be CSIA Certified Dryer Exhaust Technician® test by paying the applicable certification examination fee to the CSIA and are tested on building codes, NFPA 211, NFPA 54 standards, and all facets of cleaning and examining residential and commercial dryer exhaust systems. ​

If you are experiencing some of the aforementioned signs of a clogged or damaged dryer duct, there is a good chance there is an issue with your ventilation system.  The good news is that John C Gustafson Builder LLC can offer a solution.  There are a few different options if your dryer duct is experiencing lint build up.  If the buildup isn't attributed to a low quality ventilation system and is simply a product of time, we can offer excellent dryer duct cleaning services.  This is a routine service that should be completed every one to three years.  However, if the lint build up is the product of a low quality or a poorly planned ventilation system, then duct repair or replacement services becomes necessary depending on the severity of the situation. ​