Design . Build . Live
Modular ADU Builder in Virginia
Modular and prefab ADUs in Virginia — factory-built backyard homes, in-law suites and garage-lot cottages, delivered and finished by one design-build team.
Looking for the full rulebook — county-by-county zoning, permits, and costs? See our complete guide to ADUs in Northern Virginia.
Factory-Built Backyard Homes, Finished by One Team
A modular ADU is built in a climate-controlled factory to Virginia’s industrialized-building standards, delivered to your lot, and finished on a permanent foundation. You get the same legal, permitted accessory dwelling as a stick-built unit — often faster and with more cost certainty.
Karma Construction Group handles the entire project under one contract: feasibility, design selection, permits, foundation and site work, crane set, utility connections, and final finish-out through certificate of occupancy.
Why Homeowners Choose Modular
- Cost predictability — the factory unit is a fixed price; surprises are limited to what’s in the ground
- Speed — fabrication happens while we permit and prepare your site in parallel
- Factory quality control — built indoors, inspected at every station, never rained on
- Less disruption — weeks of on-site work instead of months of framing in your backyard
What We Handle On-Site
Modular doesn’t mean turnkey-by-truck. Every modular ADU still needs local zoning approval, a building permit, a foundation, utility trenching and connections, steps/decks/walkways, and final inspections — and jurisdictions differ on size caps, parking, and owner-occupancy. That’s the half of the project where a DMV design-build contractor earns its keep. We confirm your lot’s rules first (county-by-county details here), then match a modular unit to what your zoning actually allows.
Is Modular Right for Your Lot?
Modular shines on lots with reasonable crane access and standard utility runs. Tight urban lots, steep grades, or heavily treed yards sometimes favor a stick-built detached ADU or addition instead — we’ll tell you straight which approach pencils out better after a site visit.
Call 202.798.7663 or request a free feasibility consultation below.
FAQ
Frequently Asked Questions
How much does a modular ADU cost in Virginia?
Modular ADUs are typically more cost-predictable than stick-built: the factory-built unit price is fixed up front, and regional studies put typical completed modular ADU projects around $150,000–$200,000, with site work, foundation, and utility connections the main variables. Detached stick-built ADUs in Northern Virginia commonly run $150,000–$350,000+ by comparison.
Are modular ADUs allowed in Northern Virginia?
Yes — a modular ADU follows the same zoning rules as any other ADU in your jurisdiction (Fairfax, Arlington, Alexandria, and Loudoun each have their own size, parking, and owner-occupancy rules), plus Virginia's industrialized-building standards for the factory-built unit itself. Loudoun County is currently the most permissive, allowing detached ADUs by right.
How long does a modular ADU take to build?
Usually faster than stick-built. While the unit is being fabricated in the factory, we run permitting and prepare the site and foundation in parallel — so on-site construction time after delivery is typically measured in weeks, not months. Total project timelines depend mostly on your county's permitting path.
Our Work
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