Home Additions & Expansions
Room additions, second-story additions, bump-outs, and full expansions that seamlessly extend your living space.
When you need more space but love your home and neighborhood, a home addition is the ideal solution. JZ Development builds home additions across Long Island — from single-room bump-outs to full second-story additions — that seamlessly integrate with your existing home.
Our addition services include ground-level room additions, second-story additions over existing footprints, family room expansions, master bedroom suites, kitchen extensions, mudrooms, and sunrooms. We handle the full process from architectural planning and engineering through foundation, framing, mechanicals, and finish work.
Matching a new addition to your existing home is an art. We carefully match siding, roofline, window styles, and interior details so the addition looks like it was always part of the home — not an afterthought. On the inside, we ensure smooth transitions between old and new spaces with matching flooring, trim, and paint.
Second-story additions are a cost-effective way to double your living space without expanding your footprint. We assess your existing foundation's capacity, reinforce as needed, and build upward. The result is a dramatically expanded home on the same lot.
What We Do
- Room additions
- Second-story additions
- Family room expansions
- Master bedroom suite additions
- Kitchen extensions
- Sunroom & four-season room
- Bump-out additions
Home Additions Across Long Island
We provide home additions services throughout Nassau and Suffolk County:
Frequently Asked Questions
How much does a home addition cost on Long Island?
Home additions on Long Island typically cost $150-$350 per square foot depending on the type and finishes. A 200 sq ft room addition may cost $35,000-$65,000. A 500 sq ft family room with bathroom runs $75,000-$150,000. Second-story additions average $200-$350/sq ft. We provide detailed, transparent estimates for your specific project.
Can my foundation support a second story?
Many Long Island foundations can support a second story, but it requires professional evaluation. A structural engineer assesses your existing foundation, footings, and framing to determine capacity. If reinforcement is needed, we handle underpinning, additional footings, or steel reinforcement as part of the project.
How long does a home addition take to build?
A typical home addition takes 3-6 months from breaking ground to completion, depending on size and complexity. Simple room additions may take 2-3 months. Second-story additions and large multi-room expansions can take 4-8 months. Design and permitting add 1-3 months before construction begins.
Do I need to move out during a home addition?
Usually not. Most home additions are built from the outside in, so disruption to your daily life is minimal during the framing and exterior phases. The connection point between the new addition and your existing home is the most disruptive phase, but it's typically brief. We plan the project to minimize impact on your routine.
Will the addition match my existing home?
That's our goal on every project. We carefully match exterior materials (siding, trim, roofing), window styles, and interior finishes to create a seamless transition. A well-built addition should look like it was always part of the original home.
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Get a free estimate for your home additions project on Long Island. We're here to answer your questions and help bring your vision to life.