Do I need a permit to finish a basement in Fairfax County?

Yes. Finishing a basement generally requires a building permit under the Virginia Construction Code, plus trade permits for any electrical, plumbing, mechanical, or gas work involved. The general contractor applies for the building permit; each trade permit is pulled by the licensed contractor performing that trade.

Where do I apply for a building permit in Fairfax County?

All applications begin in PLUS, Fairfax County’s online Planning and Land Use System, administered by Land Development Services.

What happens if I remodel without a permit?

The Department of Code Compliance investigates reports of unpermitted construction and can issue a Notice of Violation requiring you to obtain permits and inspections after the fact, or remove the work.

Guide · Fairfax County, Virginia

Fairfax County Permit Guide for Home Remodeling (2026)

A plain-English walkthrough of how residential building and trade permits work in Fairfax County — what needs one, who issues it, the steps involved, and where projects get stuck. Written by a Virginia Class A contractor that files them every week.

Does your project need a permit?

Most common remodeling projects fall into one of three buckets. This is general guidance, not a substitute for the county’s official determination — when in doubt, confirm before you build:

Usually needs a permit

Building

Finished basements, additions, decks, structural changes, new or relocated walls, and installing gas appliances all generally require a building permit under the Virginia Construction Code.

Trade permits

Separate

Electrical, plumbing, mechanical (HVAC), and gas work need their own trade permits, even when the room itself isn’t changing, unless it’s a true like-for-like replacement in the same location. Each trade permit is pulled by the licensed trade contractor doing that work, under its own DPOR licence.

Often exempt

Minor work

Direct like-for-like replacement of fixtures in the same spot, sheds under 256 sq ft, most fences, and low-voltage wiring are commonly exempt — though zoning setbacks can still apply.

In Fairfax County, Land Development Services (LDS) oversees permit review, issuance, and inspections. Applications run through PLUS, the county’s online system. A separate department, Code Compliance, handles reports of unpermitted work — which is why skipping a permit can mean a Notice of Violation, stop-work orders, and having to retroactively permit or even undo finished construction.

Who issues permits in Fairfax County

Land Development Services issues the building permit; start with the county’s “Does My Project Require a Permit?” page to confirm whether your work needs one
Apply through PLUS, Fairfax County’s online Planning and Land Use System, where every application now begins
Submit drawings and documents — building plan review checks code compliance, zoning setbacks, height limits, and more
Respond to plan review comments — corrections and resubmissions are common and are where DIY applications stall
Pay fees and download your permit card and approved plans once all reviews are approved
Schedule inspections at each stage, then a final inspection — a Residential Use Permit (RUP) is issued once everything passes

The permit process, step by step

The process itself is consistent across project types: confirm the permit, apply in PLUS, pass plan review, pay, build, and pass inspections. Where owners and businesses lose weeks is in plan review comments and trade-permit coordination. A finished basement alone can pull building, electrical, plumbing, mechanical, and gas permits, each with its own inspections, and each trade permit is applied for by the licensed contractor performing that trade.

How long does it take, and what does it cost?

Timelines vary widely with project complexity and how complete your application is — a clean deck permit moves far faster than an addition that triggers zoning, health (well/septic), or fire-marshal review. Fees are set by the county’s published fee schedule and depend on project type and valuation. Because both change, we don’t quote permit fees or review times as fixed numbers — we confirm the current figures with LDS for your specific project. For official details, see Fairfax County Land Development Services at fairfaxcounty.gov, or call 703-222-0801.

Let us handle the permits

As the licensed prime contractor, Cocell files and manages the Fairfax County building permit on every project: the drawings, the PLUS application, plan-review responses, and inspection scheduling. Electrical, plumbing, mechanical and gas permits are pulled by the licensed Virginia trade subcontractors working under our contract, and we coordinate their inspections with the build schedule. Planning a project in the area? See our Fairfax and McLean service pages, or start below and a project manager will call you within one business day.

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