Full-Service High-End Residential Renovations in NYC

Design-Build Gut Renovations, Co-op Remodels & Brownstone Renovations Across Manhattan and Brooklyn

Mammoth is a woman-owned NYC design-build firm specializing in full home remodeling and gut renovations for apartments, co-ops, condos, brownstones, lofts, and townhouses across Manhattan and Brooklyn. We handle everything under one roof — interior design, material selection, DOB filings, board approvals, and construction — so you have one team accountable from concept to completion.

A bathroom with dark tropical leaf-patterned wallpaper, a window with a beige shade, a round mirror, a black hanging light, a white sink, and a faucet.

Post-War Coop Renovation

Modern kitchen with wooden cabinets, marble countertop, a vase of flowers, and two hanging pendant lights.

Park Slope Apartement Renovation

Wooden staircase with vertical slats and railing in a modern interior.

Upper East Side Gut Renovation

A narrow hallway with wood-paneled walls, ceiling, and floor, leading to a door that opens to a tiled bathroom.

East Village Post-War Gut Renovation

Modern workspace with a white desk, bookshelves, and two chairs, situated near a black column.

Castiron Building Loft Renovation

343 West 12th St close up of Wood tv stand with a tv, picture, and books in a modern room

Dining room with a wooden table, six black chairs, a white wall with a mounted flat-screen TV, two red pendant lights hanging from the ceiling, a white door, and a vase with white flowers on the table.

West Village Gut Renovation

49 columbia place Green couch, accent chair, and tv stand in a modern living room

Park Slope Townhouse Renovation

Brooklyn Heights Pre-War Renovation

Modern kitchen with marble countertops, a gas stove, green cabinets, a hanging light fixture, and a glass block wall.

Park Slope Apartment Renovation

We’re a full-service design-build studio,
and take full ownership over our projects.
Our services include:

Full-Service, Architectural & Interior Design

Our design team offers end-to-end architectural and interior design services tailored to each client's tastes, needs, and budget. We work with you to establish your layout and spatial organization, then specify every architectural element of your space — custom cabinetry, millwork detailing, plumbing fixtures, stone and tile selections through careful material selection, architectural lighting, and door hardware. Whether you're gut renovating a pre-war co-op on Park Avenue, combining two apartments in Brooklyn Heights, or redesigning a brownstone parlor floor in Park Slope, our interior designers bring the same level of rigor to every project.

Decor & Accessories

We bring your vision to life by designing and specifying every detail of your home. Our interior design and decor service covers furniture specifications, soft furnishings, decorative lighting, art selection, window coverings, and plant selection. We source from trusted vendors across the US and Europe, and our photorealistic renderings show exactly how your space will look before anything is ordered.

Regulatory

Navigating New York City's regulatory landscape is one of the most complex parts of any home improvement project — and one of the most important things we handle for our clients. We coordinate with building management and co-op or condo boards to prepare alteration agreement packages, manage the board approval process, and ensure compliance with all building codes. We work with licensed Architects of Record to handle DOB filings including Alt 2 applications, plumbing and electrical permits, HVAC system approvals, and structural changes. For landmarked properties, we manage Landmarks Preservation Commission submissions. We also handle Loft Board approvals where applicable.

Construction

Mammoth is a licensed and insured general contractor in New York City. Our construction team specializes in gut renovations, apartment combinations, bathroom remodeling, kitchen renovation, kitchen remodeling, and full home remodeling across Manhattan and Brooklyn. We manage every phase — demolition and drywall, rough mechanical and HVAC systems, bathroom renovation, cabinetry installation, living room and home office buildouts, and final finishes — with dedicated project management throughout. Your project manager tracks labor costs, budget, and timeline from day one, providing weekly progress reports and a look-ahead plan so you always know what to expect. We are committed to quality craftsmanship and exceptional results on every project.

Post-Construction

Our relationship with clients doesn't end at substantial completion. Post-construction services include a deep clean, furniture assembly and installation, TV installation, and shelf hanging. We provide a comprehensive home care package covering appliance guides, stone and tile care, HVAC maintenance schedules, and plant care — everything you need to care for your new home. Our labor is backed by a 12-month warranty. As a welcoming gesture, we'll have a bouquet waiting for you when you return home.

Home Care Guidance. Our team will prepare instructions on how to care for your new home, including:

Appliance how-to welcome packet
Plant Care
Stone & Tile Care/Best Practices
HVAC Maintenance

A post-construction Light Clean is included on all of our projects.

Two modern wooden chairs and wood closet in a simple living room