Don't just take our word for it.

See what our past clients have to say. 

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TJ Costello is great. He was exceptionally helpful during all phases of our kitchen extension and renovation. He is very patient, took all of our ideas into consideration and added so much value to the overall project. I would highly recommend him!

- Gil

I find him to be very innovative and he does a great job modernizing in a unique way. T. J.’s ability to bring a home up to date without sacrificing the style keeps the building timeless. If you have the opportunity to hire someone of this stature it is well worth its value.

- Maureen


The staff at Heirarchy is fabulous. They did a renovation and addition to our house and we absolutely love it. Not only are they creative and smart, but they also helped with all of the approvals with the town. They made our house functional for our family while maintaining its original character and charm.

- Mary Kay

TJ and staff did a major renovation to my house. We added three bedrooms, family room, new kitchen, including a master bedroom and bath. The transformation was unbelievable and everything I dreamed of....I enjoyed the whole process and it was well worth it! It was a pleasure working with them and they did a fantastic job on my house!  

- Marissa

Dear T.J., I LOVE my new kitchen! It isn’t quite finished yet, Dan still has to do the backsplash. The tiles have been ordered and will come in 2 weeks. I can not thank you enough for your expertise, your vision and especially your patience during this process. I could not have done it without you. The  small details make the kitchen and you provided these details. You are welcome over any time. It was a pleasure working with you.

- Jeanette

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Hierarchy Architecture + Design PLLC | Traditional + Contemporary Designs | Long Island Architect

Respectful of the past, excited about the future

Hierarchy Architecture + Design PLLC is a Long Island architecture firm based out of Manhasset, NY, in Nassau County. Hierarchy is one of Long Island's premier architecture and design firms, with a team of  talented architects led by Principal, T.J. Costello. We specialize in providing customers with timeless architecture solutions by creating or remodeling classic homes that are seamlessly integrated into the neighborhood's existing context. Hierarchy Architecture + Design PLLC is known for designing custom residential, primary & vacation homes in modern, contemporary, traditional or transitional styles. Our team of architects has developed an impressive portfolio of projects from large scale new building, ground-up architecture projects, to smaller more detailed requests like custom millwork. The architecture firm has become known on Long Island for its seamless residential gut renovations, and Tudor restorations, creating "new-old homes" by breathing life back into  classically designed houses. The team of architects has also done interior renovations and exterior renovations or additions for many brick colonial homes in the Tri-State area.  Aside from single-family residential projects, Hierarchy has also completed multi-family housing or institutional housing projects, as well as commercial hospitality projects, such as bars and restaurants. T.J. Costello, the Principal architect for Hierarchy Architects + Designers PLLC  is the only Long Island architect who is also Certified Kitchen Designer and most home remodels that are done often include a kitchen renovation, and bath renovation.  Follow the link to learn more about the architecture and design services we offer. For additional information or to book a consultation with us, click here to contact or view our contact information.

Copyright @ 2020 Hierarchy Architecture + Design, PLLC