White Papers

Building Code

In an effort to reduce the number of dryer fires (over 15,500 per year in the US alone) most building code has strict guidelines for properly venting a dryer. Every foot of duct run reduces airflow efficiency and small radius elbows have an even greater impact.
Complete Article . . .

State Certifications

While some municipalities are working through the process of adopting relevant code, they often accept engineering reports clarifying the improvement in airflow efficiency to allow an exception when non-specific elbow penalties are in place.
Complete Article . . .

ASHRAE Calculations

ASHRAE Fundamentals Handbook has a methodology for calculating the friction loss in ducts and fittings. Based on these formulas Dryer-Ells can be measured the same as straight pipe. This permits use of the maximum allowed run length.
Complete Article . . .

UL Fact Finding Study

Underwritings Laboratories prepared a fact find report which shows, among other findings, that Dryer-Ells are 500% more airflow efficient than sectioned, small radius elbows.
Complete Article . . .