Luxury Custom Home Additions

Hopkins & Porter has been a trusted design-build partner for homeowners throughout Northwest Washington, D.C., since 1977. We specialize in blending thoughtful design and expert craftsmanship to bring elegant, functional spaces to life. As experienced home addition contractors, we create solutions that feel intentional, natural, and truly yours.

5-Year Active Warranty | Founded in 1977 | Award-Winning Design-Build Firm

Explore

Our Home Addition Services

We design and build custom home additions that speak to your lifestyle, architectural style, and long-term needs.

Home Expansions

Whether you need larger gathering spaces or more room for a growing family, we plan and develop additions that complement your existing design. Every detail is intentional for long-lasting value and comfort.

Second Story Additions

A second-story addition expands your living space without sacrificing your property’s footprint. We carefully integrate new levels with your home’s existing structure, adding bedrooms, baths, or complete living suites while maintaining architectural integrity.

Garage Conversions

Transform unused garage space into a purposeful, finished living area. From guest suites to studios to bonus rooms, we design conversions that feel fully integrated and thoughtful.

Sunrooms

Sunrooms let in natural light and provide year-round comfort, creating a perfect connection between indoors and outdoors. We design these spaces for beauty and efficiency, adding a peaceful sanctuary to your home.

Bump-Outs

Bump-outs can significantly improve livability without major construction. We design and build bump-outs perfect for expanding kitchens, bathrooms, or key living areas with elegance.

Home Offices

We work with homeowners to create dedicated home offices designed for productivity, comfort, and architectural cohesion with the rest of the home. Every office is customized to improve focus and help you do your best work.

Open Floor Plans

We reimagine existing layouts to create new-age open floor plans for natural flow, light, and connection. All structural updates are handled with precision for both beauty and long-term stability.

Mudrooms

Mudrooms bring order, organization, and everyday convenience to your entry spaces. We design these spaces to combine storage, durability, and styling that meet your vision.

Family Rooms & Living Spaces

We create warm, inviting family rooms and living areas that foster connection and comfort. Every detail, from lighting to layout, delivers a beautiful everyday environment that makes the space feel like home.

Outdoor Living Spaces

We help homeowners expand their living areas outdoors with custom-designed patios, screened rooms, and exterior retreats. Each space is specially designed for cohesion and year-round enjoyment.

Finished Basements

A finished basement can become a living suite, entertainment space, home theater, or guest retreat. We design basements that feel polished and fully integrated with the rest of your home.

Home Gyms

From in-home strength training areas to yoga studios, we build personalized home gyms that inspire wellness every time you enter it. Each space is planned for ideal lighting, flooring, ventilation, and comfort.

Additional Dwelling Units (ADUs)

ADUs provide flexible living solutions for multigenerational families, rental opportunities, or guest accommodations. We build ADUs that match your home’s aesthetics in compliance with local regulations for DC and surrounding area home additions.

See Our Work

Get a glimpse at some of our past projects and our commitment to exceptional home addition design-build solutions.

Our Process for Home Addition Plans

(1) Initial Consultation

All custom home additions with Hopkins & Porter start by listening. We’ll clarify your goals, challenges, and vision.

(2) Conceptual Design

Our designers develop initial concepts around your vision, incorporating architecture, layout, and functionality into cohesive home addition plans.

(3) Detailed Budgeting

We provide transparent, accurate budgeting at every step so you understand costs clearly before construction begins. No surprises on the bill.

(4) Final Design & Selections

Material selections, finishes, and structural details are refined to ensure your project reflects both beauty and practicality.

(5) Construction & Completion

Our experienced craftsmen bring your vision to life with care, clear communication, and a commitment to exceptional quality in every detail.

Warranty & Long-Term Support

Our industry-leading warranty is a testament to our promise to stand behind every project we build. We support homeowners long after construction is complete, providing long-term value and peace of mind.

Key Features Include:

9-month walk-through to address settling items
18-month walk-through for continued care
23-month final check-in before the active warranty concludes
Total 2-year active warranty + 3-year structural warranty (5 years total)

About Hopkins & Porter

Founded in 1977 in Potomac, Maryland, Hopkins & Porter has grown from a two-man team into a respected design-build remodeling firm known for craftsmanship, collaboration, and excellence. Our architects, project coordinators, and skilled craftsmen (many with over 15 years of tenure) promise that every project is handled with care and precision.

The founder, Guy Semmes, has been a registered contractor in Maryland, Washington, D.C., and Virginia since 1975. Inspired by his background in archaeology, he built a company rooted in respect for structures, history, and thoughtful renovation. Mike Denker joined him to form the foundation of what Hopkins & Porter is today.

Now led by Ray Hornsby, the company continues its commitment to client-first remodeling. Guided by the belief that “remodeling is a service, not a product,” we prioritize clear communication, exceptional craftsmanship, and a supportive experience from design through construction. It’s simply the way we care.

Service Areas

NW Washington, D.C.
Bethesda
Chevy Chase
Potomac

NW Washington, D.C.
Bethesda
Chevy Chase
Potomac

Have a question?

Frequently Asked Questions About Custom Home Additions

What should I consider when planning a home addition?

When planning a home addition, consider your long-term needs, zoning regulations, budget, and structural requirements. Most importantly, think about how the new space will integrate with your existing home. Thoughtful design, realistic timelines, and choosing an experienced design-build firm make all the difference for cohesion, functionality, and a smooth construction process.

Should I add a custom home addition or buy a bigger home?

Adding a custom home addition is ideal when you love your neighborhood, want personalized design, or prefer to avoid moving costs and stress.

Buying a bigger home may be better if zoning is restrictive or major structural changes are needed. Compare your financial impacts, lifestyle goals, and long-term property value before deciding.

What are common types of home additions and their uses?

Common home additions include second-story expansions for additional bedrooms, bump-outs for larger kitchens, sunrooms for natural-light living, garage conversions for guest suites or offices, and ADUs for rental or multigenerational living. Each option can improve function, storage, or lifestyle flexibility while improving the flow of the home.

What is the 30% rule for renovations?

The 30% rule refers to homeowners reserving an additional 20–30% of their renovation budget for unexpected conditions or design adjustments. This guideline provides a financial buffer for structural discoveries, material changes, or unforeseen requirements, making sure the project stays on track without compromising quality or scope.

What home additions add the most value to a house?

Additions that add the most value typically involve primary suite expansions, additional bedrooms, finished basements, open-concept living areas, and kitchen enlargements. ADUs and home offices have become increasingly valuable due to lifestyle and market trends.

Book a Home Addition Consultation

Connect with our team to discuss your vision and begin planning your custom home addition today.