Home Addition – West Windsor Township, NJ
This 900-square-foot home addition in West Windsor Township started with a deck demolition and ended with five new interior spaces, a new deck, and a fully extended mechanical system. In between: a load-bearing kitchen wall came out, and a steel beam on two steel columns went in to hold the second floor and roof above it. The structural work is what made everything else possible. Note: The project page body text references 700 square feet; the project data table shows 900 square feet. The 900-square-foot figure from the data table is used here as the authoritative scope.
What This Project Included
- Demolition of the existing deck to clear the footprint for the new addition
- Removal of load-bearing kitchen wall section
- Steel beam installation supported by two steel columns
- New kitchen with custom cabinets, white quartz countertops, peninsula, recessed lighting, and new appliances
- New bathroom with walk-in shower, glass doors, double vanity, recessed lighting, mirrors, toilet, and fixtures
- New dining room connected to the kitchen
- New bedroom with lighting and finishes
- Laundry room upgrade with new plumbing, electrical, and finishes
- New deck adjacent to the addition
- Full extension of electrical, plumbing, and HVAC into all new spaces
How a 900-Square-Foot Addition Begins: Clearing the Footprint
The existing deck was in the location where the addition needed to be built. Before any foundation work or framing could begin, the deck had to come down. Demolishing an existing structure to build a new one is a standard part of addition projects where the homeowner is expanding into space that is currently occupied by something else — in this case, an outdoor deck. The demo phase clears the footprint, disposes of the material, and prepares the ground for whatever foundation approach the new structure requires.
This sequencing — demo first, then build — means the project timeline begins before any visible construction starts. Homeowners who have not been through an addition before sometimes underestimate how much of the schedule is preparation: demo, excavation, foundation, framing, rough-in. The finished rooms come at the end.
The Structural Work: Beam and Columns
Adding 900 square feet to a house requires rethinking where the house begins and ends — and in this project, that included removing a section of the kitchen wall to create an open connection between the existing kitchen and the new spaces. The wall that came out was load-bearing: it was carrying the weight of the floor and roof structure above it. Removing a load-bearing wall without replacing its structural function would cause the structure above to sag or fail.
The replacement is a steel beam — a horizontal structural member spanning the opening — supported at each end by a steel column. Steel is used here rather than a wood beam because the span required a member with a higher load capacity than dimensional lumber can reliably provide at that width. The two steel columns carry the beam load down to the foundation. This is standard structural engineering for a wall-removal opening of this size; the result is a clear, column-supported opening between the kitchen and the new addition that reads as part of the original house rather than a patched connection between old and new.
Five New Spaces
The 900 square feet of new interior space was organized into five distinct areas, each with its own function and finish scope:
Kitchen: The new kitchen includes custom cabinets, white quartz countertops, a large peninsula that adds workspace and seating, recessed lighting, and new high-end appliances. The peninsula is the organizing element — it defines the cooking zone, provides prep space, and creates a surface for casual dining without requiring a separate table. White quartz countertops are low-maintenance, heat-resistant, and consistent across the full surface without the variation that natural stone introduces.
Bathroom: A full bathroom was designed and built from scratch within the addition — walk-in shower with glass doors, double vanity, recessed lighting, mirrors, toilet, and fixtures. Building a bathroom in an addition requires running new supply lines and drain lines from the home’s existing plumbing stack to the new location, and extending the electrical to support the lighting and exhaust. Nothing in this room was pre-existing.
Dining Room: A new dining room was built directly adjacent to the kitchen, connected to provide a natural flow from cooking to eating. The spatial relationship between the kitchen and dining room in this addition — open and connected through the structural opening created by the beam-and-column work — is what makes the addition function as an extension of the home rather than a separate building grafted onto it.
Bedroom: A new bedroom was added with appropriate lighting and finishes. A bedroom in an addition requires the same electrical, HVAC, and insulation work as any other habitable space — it is not a storage room or utility space, it is a room people sleep in, which means it has to meet the same comfort and code standards as the rest of the house.
Laundry Room: The existing laundry room was upgraded as part of the project — new plumbing, new electrical, and updated finishes. An addition project of this scale often triggers upgrades to adjacent spaces that were workable before but benefit from attention while the trades are already on-site.
The New Deck
A new deck was built adjacent to the addition at the conclusion of the project. The original deck was demolished to make room for the addition; a new deck restores the outdoor access that the addition footprint displaced. The new deck is appropriately scaled to the addition and provides a transition between the new interior spaces and the yard.
Systems Extension
900 square feet of new space requires 900 square feet of electrical, plumbing, and HVAC coverage. The extension of these systems into the addition of new circuits from the panel, new supply and drain runs for the kitchen and bathroom, new HVAC ducting or units serving the new spaces, is the work that is invisible in the finished rooms but essential to making them function. An addition that has beautiful finishes but inadequate heating, improper plumbing, or underserviced electrical is a problem waiting to manifest. All of that work was done properly here as part of the permitted project.
Home Additions in West Windsor Township
West Windsor Township is a Mercer County municipality in central New Jersey, with established residential neighborhoods and a mix of home types from the late 20th century. Adding square footage to an existing home — rather than moving to a larger one — is a common decision in communities where the school district, neighborhood, and location are valued enough to justify the investment in expanding the existing property.
Belmax Remodeling works throughout West Windsor Township and the broader Mercer County and central NJ region. For more on our addition work, see our home addition service page. Homeowners in West Windsor can also visit our West Windsor home addition page for more completed local projects.
Considering a Similar Project?
Home additions in the 900-square-foot range with full interior buildout — kitchen, bathroom, dining room, bedroom, laundry, structural beam work, deck, and full systems extension — typically fall in the $110,000–$145,000 range in central New Jersey. This West Windsor project came in at $125,000 completed in September 2024. To discuss what your addition would involve, request a free estimate.