Montgomery County Building Permits: The Homeowner's Survival Guide

Understanding building permits in Montgomery County, Maryland is the difference between a project that starts on time and one that's delayed by months. And there are two kinds of people in MoCo: those who have navigated the Department of Permitting Services, and those who still have hope in their eyes.

I'm exaggerating. Slightly. DPS is staffed by competent people doing important work. But the permitting process for new residential construction in MoCo was clearly designed by someone who believes that if a thing is worth doing, it's worth doing through seven different agencies with overlapping jurisdictions and no shared calendar.

Most homeowners never learn how this process works because their builder handles it. Which is fine — until you realize that permitting delays are the #1 cause of construction timeline overruns, and you have zero visibility into why your project hasn't started yet.

This is the permit guide that builders keep as institutional knowledge. I'm writing it down because Iron Gate's entire philosophy is that homeowners deserve to know what's happening with their own project.

The Six Permits (and Reviews) You'll Probably Need

1. Building Permit (DPS)

The big one. Issued by Montgomery County's Department of Permitting Services. Covers structural, mechanical, electrical, and plumbing work. Your architectural plans must be stamped by a licensed architect or engineer. DPS reviews plans for code compliance, and they're thorough. First-pass approval is rare. Plan for at least one round of revisions.

2. Stormwater Management (DPS)

If you're increasing impervious surface (which you almost certainly are on a teardown-to-new-build), you need a stormwater management plan. This involves engineering calculations, site grading plans, and one or more stormwater management facilities — anything from an infiltration trench to a bioretention area.

This permit can run concurrently with the building permit if your civil engineer coordinates early. If not, it becomes a sequential delay that adds weeks.

3. Sediment Control (DPS / MDE)

Required before any land-disturbing activity. This includes demolition, grading, and excavation. You cannot move dirt without an approved sediment control plan. The Maryland Department of the Environment (MDE) may also be involved depending on the size of the disturbance.

This is the permit that gets people fined. Start grading without it and you'll meet the enforcement team faster than you'd like.

4. WSSC (Water & Sewer)

Washington Suburban Sanitary Commission handles water and sewer connections. If you're upsizing the home significantly, you may need to upgrade your water meter, replace the sewer lateral, or install a new connection. WSSC has its own plan review process, its own fee schedule, and its own timeline that exists in a parallel dimension from the rest of the permitting world.

5. Tree/Forest Conservation (MNCPPC / DPS)

Montgomery County's forest conservation law is among the strictest in the region. If your lot has significant tree canopy, you may need a forest conservation plan, tree-save plans, and posted bonds for trees that will be impacted. The Maryland-National Capital Park and Planning Commission (MNCPPC) reviews certain aspects, while DPS handles others.

The intersection of tree preservation and building envelope is where some of the most expensive surprises in MoCo construction live.

6. HOA / Architectural Review / Municipal Review

If your property is in an HOA, a municipality like the Town of Chevy Chase, or a special district, there may be additional design review requirements. These can range from minor (material and color approval) to significant (full architectural review with design guidelines). These reviews typically need to happen before you submit to DPS, because DPS may require evidence of local approval.

The Critical Path: What to File First

Not all permits are sequential. Here's how to run them efficiently:

Phase 1 (concurrent): Sediment control, stormwater management, WSSC plan review, and HOA/architectural review can all begin simultaneously while your building permit is under DPS review.

Phase 2 (sequential): Building permit must be issued before construction begins. Sediment control must be approved before demolition or grading. WSSC inspections happen during construction at specific milestones.

The families who lose months are the ones who file permits sequentially — waiting for one approval before starting the next application. The families who stay on schedule are the ones whose team files everything in parallel on Day 1.

This is, frankly, one of the highest-value things a construction consultant does. Permit sequencing isn't glamorous, but getting it wrong costs more time than almost any construction delay.

Common Rejection Reasons (And How to Avoid Them)

Incomplete submissions: DPS will bounce your application if anything is missing. Architectural stamp, structural calculations, energy compliance documentation, site plan — every piece must be there on first submission or you go to the back of the line.

Zoning non-compliance: Your design exceeds FAR, violates setbacks, or triggers a use restriction. These are the errors that should have been caught when you evaluate the lot's buildability — before design even started. Make sure you understand setback requirements before submitting for permits, and review building coverage and setback calculations to avoid costly redesigns.

Stormwater conflicts: Your stormwater management plan doesn't adequately address runoff for the proposed impervious area. This often requires civil engineering revisions, which take time.

Tree conflicts: Your proposed building footprint, grading plan, or construction access impacts protected trees in ways that weren't addressed in your forest conservation plan.

The theme: nearly every rejection is preventable with proper upfront analysis. The lot feasibility work we do at Iron Gate isn't just about understanding costs — it's about identifying permitting landmines before you step on them.