Thinking about adding a deck or porch to enjoy more outdoor time at home? The permitting process can feel like a hurdle, especially when timelines and requirements are unclear. The good news for McLean homeowners is that Fairfax County offers a faster path for many residential decks. In this guide, you will learn who issues permits, what to submit, and how to position your project for a quick review. Let’s dive in.
McLean permits run through Fairfax County
McLean is part of unincorporated Fairfax County, so county agencies handle your building and zoning permits. You will apply through Fairfax County’s Planning, Permitting and Construction system, not a separate McLean office. The county’s Land Development Services explains programs and timelines on its Building Plan Review page.
Do decks and porches need permits?
Yes. In Fairfax County, building a deck or porch is reviewed under the Residential Addition/Alteration (ALTR) record. Separate trade permits are needed if you add electrical, plumbing, or mechanical work. The county’s Addition/Alteration permit library outlines what to file and how to label your documents in the PLUS portal.
Fast Track and 3-day deck reviews
Fairfax County offers a Fast Track program for non-complex residential projects, and decks are eligible. Fast Track prioritizes simple, construction-ready plans and reviewers may move complex plans to standard queues. You can see eligibility and process details on the Fast Track program page.
Even better, the county now targets a comprehensive review of residential deck plans within three business days for complete, eligible applications that do not require complex site reviews. This applies to first submissions and resubmissions when your package is complete. The county announced this change in its deck review turnaround update.
What qualifies for the quick path
- Your application is complete and clearly labeled.
- The deck is non-complex and does not require additional agency reviews.
- The project does not encroach into a Resource Protection Area or floodplain.
- Plans align with county prescriptive standards or include sealed engineering.
What to submit in PLUS
A clean, complete package is the fastest route to approval. For most decks and porches, prepare:
- PLUS application: file the Residential Addition/Alteration (ALTR) record and select Deck for the type of work. See the ALTR permit library for instructions.
- House location plat or survey: show property lines, the home, setbacks, and where the deck or porch will go.
- Construction documents: use Fairfax County’s Typical Deck Details for single-level, prescriptive decks. If your design is multi-level, supports a hot tub, or deviates from the prescriptive tables, provide sealed engineered drawings.
- Cover sheet and file naming: follow first-submission requirements on the ALTR page so reviewers can navigate your files easily.
- Permit authorization: include the affidavit if the applicant is not the owner or a licensed contractor.
- Related reviews: address Resource Protection Area or floodplain issues before applying. Start with the county’s RPA FAQ.
- Trade permits: apply for electrical or other trade permits if you plan outlets, lighting, or similar features.
Steps to speed your approval
- Confirm eligibility. Keep the design simple and outside RPAs and floodplains.
- Use the county’s Typical Deck Details if your project fits the limits.
- Prepare a clear plat and label files exactly as the county requests.
- Have your licensed contractor submit and manage the permit to reduce errors.
- Upload a complete package the first time. Incomplete submissions are moved to standard queues.
Inspections after permit issuance
Once the permit is issued, schedule inspections at required stages such as footings/piers, framing and ledger attachment, and final. If you have trade permits, those inspections are separate. The county’s Typical Deck Details include inspection expectations and the on-site records you should keep.
Fees and timing realities
Fairfax County updated its fee schedule in 2024 and has changes effective July 1, 2025. Fees are assessed based on your application date, so verify current amounts at submission. You can review the county’s fee schedule in Appendix Q.
Review times still depend on workload and whether additional agency reviews are needed. The three-business-day target applies to eligible, complete deck submissions. Complex plans and site issues follow standard timelines.
When to involve a pro
If your deck is multi-level, near a stream, or includes special loads like a hot tub, bring in a licensed engineer and experienced contractor before applying. Their plans and site strategies can keep your project on track and help you avoid multiple review cycles.
Ready to plan updates that add value before you sell or to prep a new purchase? Reach out to Maggie Daley for a practical, client-first game plan tailored to your goals in the DC area.
FAQs
Do I need a permit to build a deck in McLean?
- Yes. Fairfax County requires a building permit under the Residential Addition/Alteration record for decks and porches, with separate trade permits if you add electrical, plumbing, or mechanical work.
How fast can Fairfax County approve my deck plans?
- If your submission is complete and eligible, Fairfax County targets a comprehensive deck review in about three business days. Complex projects follow standard timelines.
Can I use county Typical Deck Details instead of engineered plans?
- Yes, for single-level, prescriptive decks that fit the county’s limits. Multi-level designs, hot tubs, or deviations usually require sealed engineering.
What if my McLean property is near a stream or floodplain?
- Decks that encroach into Resource Protection Areas or floodplains require additional technical review and are not eligible for the quick three-day path.
Which permit type do I select in PLUS for a deck?
- Choose the Residential Addition/Alteration (ALTR) record and indicate Deck under type of work.
What inspections are required for a new deck?
- Expect footings/piers, framing and ledger attachment, and final inspections. Trade permits, such as electrical, also require their own inspections.
