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We've moved from Annapolis to Upper Marlboro!
For details, click here.

WELCOME TO H&D MECHANICAL'S WEBSITE

Founded by Sean Duffy and Erik Harley in 2009, H&D Mechanical is a mid-size mechanical contractor based in Upper Marlboro, Maryland. H&D has an established record of superior work in a variety of settings, including medical, scientific and commercial projects.

For a map of our location, please click here.

For information about Harley & Duffy, our residential plumbing, heating and air conditioning services branch, please visit:
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