Fairfax County · VA

Home Additions in Herndon

An addition is the one project where zoning can stop you before design starts. We are a licensed contractor in Virginia (Class A #2705183185) — we pull the permits through Fairfax County Land Development Services, coordinate the licensed trades, and hand you a written line-item scope before demolition starts.

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Permits & inspections in Fairfax County

The paperwork is the part most contractors gloss over.

An addition starts with zoning, not construction: setbacks, lot coverage and height limits get reviewed before a building permit is issued, and in some neighborhoods there is a stormwater or historic review on top. Then come the footing and foundation inspections, which have to pass before backfill. This is the longest-lead permit of any project we do, and it is why we start the paperwork while the design is still being drawn.

Your Herndon permit goes through Fairfax County Land Development Services. We pull it under our license and we hold the inspection schedule — you do not chase inspectors and you do not sign the application.

Local to Herndon

The Town of Herndon issues its own permits for properties inside town limits, separate from Fairfax County, and the town has a historic district downtown with its own design review. Herndon addresses straddle the town line, so we confirm which applies before filing.

What we find in Herndon homes

The house decides half the scope.

Herndon's older core is early- to mid-20th-century housing on small lots; around it is 1970s–1990s subdivision and townhome development. The older houses commonly need electrical and plumbing brought forward as part of any kitchen or bath scope.

What's included
  • Zoning, setback and lot-coverage review before design is finalized
  • Footings placed below the regional frost line
  • Footing and foundation inspections passed before backfill
  • Roofline, siding and HVAC tied into the existing house so it does not read as an add-on
Planning range — Fairfax County
$180 – $340 / sq ft

A planning range, not a quote. Your written line-item price comes after a free on-site walkthrough. HVAC, electrical and plumbing are performed by licensed trade partners.

2017020171RestonSterlingChantillyOak Hill

Free Herndon walkthrough

A written, line-item scope for your home additions project. No design fee, no obligation.

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Also in Herndon

One contractor for the rest of the house

Our Herndon crews cover Reston, Sterling, Chantilly, Oak Hill and every ZIP in the area — 20170, 20171.

Herndon home additions questions

Straight answers

Do you handle home additions in Herndon, VA?

Yes. United Developers is a licensed contractor in Virginia (Class A #2705183185) and works throughout Herndon and Fairfax County, including 20170, 20171 and nearby Reston, Sterling, Chantilly.

Who pulls the permit for a Herndon home additions project?

We do, under our license, through Fairfax County Land Development Services. An addition starts with zoning, not construction: setbacks, lot coverage and height limits get reviewed before a building permit is issued, and in some neighborhoods there is a stormwater or historic review on top. Then come the footing and foundation inspections, which have to pass before backfill. This is the longest-lead permit of any project we do, and it is why we start the paperwork while the design is still being drawn.

Is there anything specific to Herndon I should know?

The Town of Herndon issues its own permits for properties inside town limits, separate from Fairfax County, and the town has a historic district downtown with its own design review. Herndon addresses straddle the town line, so we confirm which applies before filing.

What does home additions cost in Herndon?

Most Herndon projects land in the $180 – $340 / sq ft range. That is a planning range for Fairfax County, not a quote — your written price comes after a free on-site walkthrough.

Is the Herndon walkthrough and estimate free?

Yes. The walkthrough and the written scope are free and yours to keep whether or not you hire us. There is no design fee and no consultation invoice.

How long does an addition actually take?

The build is rarely the long part — permitting and zoning review are. Expect the approval phase to run in parallel with final design, and expect us to give you a schedule that names the permit milestone rather than hiding it. We will tell you at the walkthrough if your lot has a setback or coverage problem, because that changes the whole conversation.

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