AIA Virginia > Member Firm Directory > Single-Family Residential > Willoughby Design, LLC Print Return to Directory Categories Single-Family Residential Address 1 P.O. Box 651145 City POTOMAC FALLS State Virginia ZIP Code 20165 Phone Number 703-472-4006 Website http://www.willoughbydesignllc.com Areas of Practice/Specialties Single-family residential Project Delivery Methods Traditional project delivery – Design-Bid-Build, Design-Build Ratings There are no reviews yet. Please login to leave a review.