How long does a home addition take in Glen Echo?

A home addition in Glen Echotypically runs 6 to 16 months from your first design conversation through move-in day, with a median of about 11 months, figures drawn from 159 completed MOSS addition projects across the DMV. That span covers three distinct phases: design and selections (where the floor plan, materials, and specifications are finalized),permitting and approval through Montgomery County, and actual on-site construction. The build itself, while the most visible phase, is only one piece of that total timeline.

Where your project lands within that 6-to-16-month window depends on several factors. Scope and structural complexity matter enormously, a simple bump-out moves faster than a second-story addition touching the existing roofline, foundation, or load-bearing walls. On the permitting side, Montgomery County's Department of Permitting Services typically takes 20 to 30 business days from a complete submission to issue a permit, but projects requiring resubmission cycles can add 7 to 10 days per round. Older Glen Echo housing stock, much of it built mid-century or earlier, can surface surprises once walls open, from outdated electrical panels to undersized structural members that need addressing before framing can proceed. Long-lead materials like custom cabinetry and specialty windows can also stretch the schedule if they aren't ordered well in advance.

MOSS's design-build model is specifically structured to compress that timeline wherever possible. Because our architectural, design, and construction teams operate as one unit, permit packages are prepared with Montgomery County's review criteria in mind from the start, reducing the likelihood of revision cycles that cost weeks. We also identify long-lead items early in the design phase and place orders before permits are even in hand, so materials arrive in sync with the construction schedule rather than after it has already stalled.