What's Included in Home Addition Services
- Space Planning & Design - Maximize new living space while respecting your home's existing style and roofline
- Structural Engineering - Ensure additions integrate properly with existing home foundations and framing
- Architectural Integration - Match materials, rooflines, and details so additions blend seamlessly with your house
- Complete Permitting - Handle all building codes, zoning requirements, and county approvals for Northern Virginia jurisdictions
- Foundation to Finish - Manage excavation, framing, systems, and interior finishes from construction begins to completion
- Exterior Matching - Source materials that match existing siding, brick, windows, and trim for cohesive appearance
What Could a Room Addition Bring to Your Home?
Second Story Addition
Add an entire floor above your existing home. Perfect for split-level homes or ranchers where lot size limits ground-level expansion. Create multiple bedrooms, bathrooms, and living areas while keeping your backyard intact.
Master Suite Addition
Build your dream primary bedroom with a luxury bathroom and a walk-in closet. First-floor master suites help families plan for aging in place, while second-story additions provide private retreats away from main living areas.
Bump Out Additions
Extend existing rooms by 3-8 feet. Kitchen bump-outs add counter space and room for islands. Bathroom bump-outs accommodate double vanities. Living room bump-outs create space for built-ins or dining areas. Most cost-effective addition type when you need just a bit more room.
In-Law Suite & Accessory Dwelling Units
Create a self-contained living space for aging parents or adult children. Full in-law suites include a bedroom, bathroom, kitchenette, and own entrance—providing family proximity with independence. Great rooms converted to accessory dwelling units add the most value for multi-generational families.
Family Room & Great Room Additions
Expand your main living area with a dedicated space for your growing family. Open-concept great rooms connect seamlessly to kitchens. Sunroom additions bring natural light and year-round outdoor views.
Garage Addition & Conversions
Add garage space for extra vehicles and storage. Alternatively, garage conversions transform existing garages into finished living spaces like home offices, guest suites, or extra bedrooms.
Our Home Addition Process
Planning & Design
We evaluate your existing home, discuss your family's evolving needs, and explore addition options. Our team develops plans that maximize new space while ensuring additions match your house architecturally and meet all building codes.
Permitting & Construction Begins
Once design is approved, we handle zoning applications and building permits. Construction begins with foundation or structural prep, then framing, roofing, and exterior work to weatherproof the addition before interior finishes.
Interior Finishes & Integration
We complete interior work that seamlessly blends new space with existing rooms. Material selections, trim details, and flooring transitions ensure your addition feels like part of the original house.
Industry-Leading Manufacturers Behind Every Horizon Home
Our commitment to luxury quality extends beyond our craftsmanship. It's reinforced by exclusive partnerships with the industry's most trusted manufacturers; granting access to premium materials and expert technical support throughout your project.
Visit the Homes We’ve Built
for Families Like Yours
A Precisely Tailored Masterpiece of Transitional Elegance
This townhouse renovation is a precisely tailored masterpiece, transforming a compact urban space into a home that balances modern functionality with exquisite transitional elegance. We delivered a seamless, white-glove experience, ensuring every material—from the mahogany door to the herringbone tile—was executed with uncompromising precision and design integrity.
Coastal Warmth on the Potomac
This waterfront home on the Potomac River is a masterwork in meticulous site planning, capturing the enduring character of a classic coastal retreat despite the constraints of new construction and strict shoreline regulations. Our proven process delivered a design anchored by a vast, 60-foot screened porch that seamlessly connects indoor and outdoor spaces, creating an exceptional sanctuary for entertaining and relaxation. The finished home blends Italian-inspired masonry accents and natural wood to achieve a sense of timeless warmth and refined craftsmanship.
Why Homeowners Choose Horizon for Home Additions
End-to-End Architectural Integration
Our additions don't look like additions. We match rooflines, match materials, and design transitions that make the new space feel original to your home. Many visitors can't identify where the house ends and the addition begins.
Experienced Addition Specialists
We've built hundreds of room additions across Northern Virginia. We understand structural challenges, know how to tie into existing foundations, and ensure new roofs integrate properly with your home's existing roof system.
Complete Code Compliance
Every Northern Virginia jurisdiction has specific requirements for additions. We know setback rules, height restrictions, and coverage limits for Fairfax County, Arlington, and the surrounding areas. We handle all approvals so your project stays on track.
Cost-Effective Solutions
Bump outs and other strategic additions often cost less than moving when you factor in real estate commissions, closing costs, and market conditions. We help you determine the most cost-effective way to gain the space you need.
FAQs about Room Additions
Horizon Building offers true design/build integration. We manage your entire home-building process under one contract. Our team partners with you to provide architectural design, permitting, and construction management - all through a single experienced team. Our reputation in Fairfax County, Loudoun County, and Arlington is a testament to our commitment to exceptional customer service and customer satisfaction.
Luxury custom homes in Northern Virginia typically range from $1.2 million to $5 million+, depending on location, size, and finishes. Whole-home remodels generally range from $400,000 to $2 million. Primary factors affecting your investment include site preparation requirements, architectural design complexity, material selections, and square footage.
Most custom home construction projects take 14-18 months from architectural design to move-in. This includes design development (2-4 months), permitting (2-3 months), and construction (10-12 months). Whole-home remodels typically require 6-12 months. Timeline factors include county permitting processes, site preparation needs, and material lead times.
Yes. Horizon Building primarily serves all of Northern Virginia, including Fairfax County, Prince William County, Arlington, Alexandria, Vienna, VA, McLean, Falls Church, and Annandale. We also serve Montgomery County, Maryland, Loudon County, and rural areas around the DC Metro and Richmond areas on case-by-case basis.
Absolutely. Our experienced team knows every jurisdiction's requirements, reducing delays that plague projects managed by less knowledgeable builders. We schedule all inspections, address any concerns immediately, and ensure your home is built to meet or exceed all code requirements.
Your first meeting is complimentary and pressure-free. We'll discuss your vision, lifestyle needs, timeline expectations, and budget. We'll review relevant projects from our portfolio, explain our design/build process in detail, and answer every question you have. If your project involves a specific site (either land you own or are considering), we can evaluate it for feasibility.
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Your Project?
Experience the Horizon Building difference. Schedule a consultation to discuss your vision with Northern Virginia's most trusted design/build firm.