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Don't just take our word for it.

See what our past clients have to say. 

Working with TJ from Hierarchy was wonderful! He is an extremely talented architect and was the ultimate professional. I thought his ideas reflected what he knew would work with our lifestyle and ultimately we got a wonderful outcome. His work was timely and because of his easy going manner he worked well with the contractor and decorator. At one point the project was completely different and over time we decided that the expansion was more then we wanted. In the end we made great choices and TJ was a huge help in the decision making process. I would highly recommend him and his team!   

- Patti


You could not tell where the new additions began and the original structure throughout… The staff is amazing and always helpful. They are all very professional. They took care of all the necessary town permits, review boards, and there was never an issue with the Building Inspectors either. Any problems that arose were taken care of and T.J. took full responsibility. I highly recommend using Hierarchy! T.J. is a gentleman beyond belief. His main concern is making sure the customer is satisfied and his level of expertise gives you a great project!

- Heather

Hi T.J. I hope all is well. I checked out the magazine and it’s a great piece! I remember that house from your Christmas party and I really loved it. I  always appreciate those special elements you create when working with space. Lots of people can make rooms look great, but not everyone has the vision to create something special and unexpected that surprises out of existing space. Best, Anja D’Angelo"  

- Anja

Showcase Kitchens

We work with Hierarchy Architects frequently. Not only do we enjoy their easy-to-work with manner, but our clients do as well. TJ Costello is an honest, friendly gentleman who brings a unique brand of intelligence to every project. TJ's approach to a job is always multi-faceted, seeing not one, but several solutions to the renovation. In the end, his work is seamless to the environment; an outcome that always exceeds expectations. When Hierarchy is on the job, you can rest assured that their years of know-how and soup to nuts oversight will be instrumental to the getting job done right the first time.

- Showcase Kitchens

There are many reasons that Hierarchy is considered to be Manhasset's premier architectural firm. The depth of knowledge that TJ Costello and his entire team bring to a project is extraordinary. Their easygoing professionalism makes them easy to work with and responsive to all questions,  suggestions and needs. They designed a new portico and a second story addition for our home. Both look as if they always been here, which we believe to be the ultimate sign of a successful renovation. What is most impressive about TJ is his attention to detail. For example, he was driving by our house one day when shutters were being installed. He stopped his car and instructed the workers to move the "S" hooks on the shutters over about an inch or so. This is just one instance of his eye for particulars and level of commitment that made our project a success. We highly recommend Hierarchy.

- Julie


I am freshly off a one year, major renovation of my 1930 Farmhouse...I met with four architects and chose Hierarchy because they suggested they  would design for me a version of what I wanted in a form that I could afford, that could be built in a timely basis, and would be "exactly" what I wanted, only better! I have learned over this time that being a good architect demands a long list of skills and talents that are not so obvious before  hiring architect must listen carefully and understand what you want, and bring to you multiple designs, and ideas that capture what you want in a version that is so much better, more elegant, more sophisticated, and in a better form of design and engineering then you ever having someone interpret your dreams for your home in to a functional, affordable form that can be executed on site by others. That's what TJ Costello does. And he makes it end up loving the process. Remember, your architect isn't swinging a hammer, so his drawings and plans have to be clear, and perfectly drawn. The plans Hierarchy drew were literally perfect....down to every electrical plug, light, wire, wall, stud, and especially structural elements. Every tradesmen examined the plans without question and every town and village official approved all plans (and changes) immediately. The Hierarchy staff (especially TJ Costello) are imaginative and creative and can see solutions where there is not obviously one...TJ has ideas for everything that comes up, and is so generous to offer them, no matter how small, or complicated...and I had lots of both! We had so many issues that we had to seek his consult (and his excellent staff) I can't even recall...He was always available by some form (e.g. phone, email, text, etc) you never felt that there wasn't a "source" to go to with a question. When I talked about lighting fixtures he gave me his personal ,architects version of a massive catalog where we ended up buying all our fixtures...when we complained about a vendor's performance he called them on my behalf and got them on track...he really is like your smart, creative best friend, that you can call and visit and get just the perfect solution...he has great taste, and excellent style...and offers all this to you as a client. He and his staff are really " Yes " people. They just get things done. And his fee? Okay...maybe not the cheapest, but very fair, and once your are a client, you have the perfect partner to share every concern, question and even celebrations. He and his staff are as happy for us now that the job is done, as we are. Look....there are lots of architects you can hire...but for the creativity, imagination, "easy-to-work-with" attitude, accessibility intelligence, ....there is no other firm you can a better result from then Hierarchy.

- Mitch

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