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Addition to existing structure builders in East Islip

Concorde Remodeling, Inc.
8 Lynam Court
4.69(
41
)
Approved Pro
Concorde Remodeling, Inc.
8 Lynam Court
4.69(
41
)
Approved Pro
Super Service Award
Customers say: Quick response
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
17 years of experience

We are a locally owned and operated company serving the Long Island area. We are committed to excellence in everything we do. Remodeling is our passion and customer service is our specialty. Please call Concorde Remodeling, Inc., today! *DOES NOT HANDLE INSURANCE CLAIMS *

"I recently had the pleasure of working with Bob from Concorde on the finishing of a basement into an apartment, and I am thrilled with the results. From start to finish, the entire process was handled with remarkable professionalism and attention to detail. **Project Management:** Rob, the project manager, was outstanding. He maintained excellent communication throughout the project, keeping me informed of progress and any potential issues. **Quality of Work:** The quality of work delivered by Concorde was exceptional. Every aspect of the construction was executed to the highest standards, from the foundation to the final touches. **Overall Experience:** Overall, my experience with Concorde was nothing short of excellent. They delivered a high-quality construction project that met all my expectations and more. I highly recommend Concorde for any construction needs and will certainly consider them for future projects."

Chrysanthy P on May 2024

We are a locally owned and operated company serving the Long Island area. We are committed to excellence in everything we do. Remodeling is our passion and customer service is our specialty. Please call Concorde Remodeling, Inc., today! *DOES NOT HANDLE INSURANCE CLAIMS *

"I recently had the pleasure of working with Bob from Concorde on the finishing of a basement into an apartment, and I am thrilled with the results. From start to finish, the entire process was handled with remarkable professionalism and attention to detail. **Project Management:** Rob, the project manager, was outstanding. He maintained excellent communication throughout the project, keeping me informed of progress and any potential issues. **Quality of Work:** The quality of work delivered by Concorde was exceptional. Every aspect of the construction was executed to the highest standards, from the foundation to the final touches. **Overall Experience:** Overall, my experience with Concorde was nothing short of excellent. They delivered a high-quality construction project that met all my expectations and more. I highly recommend Concorde for any construction needs and will certainly consider them for future projects."

Chrysanthy P on May 2024


Avatar for i Riverdale Construction, Inc.
i Riverdale Construction, Inc.
31 Casino Street, Apartment 1F
4.38(
24
)
Approved Pro
i Riverdale Construction, Inc.
31 Casino Street, Apartment 1F
4.38(
24
)
Approved Pro
Customers say: True professional
13 local quotes requested
11 years of experience

iRiverdale Construction, Inc. is one of New York's elite general contractors, specializing in a diverse range of residential and commercial projects. As a family-owned and operated business with over a decade of experience, we are recognized as masters in our field. Whether you need a concept for your project or want to bring your vision to life, we create stunning works of art tailored to your needs. No matter the size or scope, we apply our unique skill set to ensure your project's success, treating your property with the same care and attention we give our own. Our satisfied repeat customers consistently return to us for new projects, and we are always eager to welcome new clients. Contact us today to schedule an initial consultation and discuss how we can help turn your project into a reality.

"I hired Riverdale construction through a colleague of mine she had worked on on her home and she said this company that is owned by Raquel Diamond is a smart skilled and professional and friendly her team transformed my full basement with adding columns with opening walls for more space. Including moving my bathroom and my laundry room The project manager Jay kept me informed throughout the whole process , always available to answer questions,I felt like they were really listening to our needs.They worked efficiently and stayed on track no delays or unexpected setbacks.
The crew was polite and respectful They cleaned up thoroughly after each day Everyone on the team seemed highly skilled.They went above and beyond toaddress any issues They were very accommodating to our needs. They followed up after the project was completed to ensure I was completely happy . I would recommend I Riverdale Construction and Raquel Diamond to anyone who wants to remodel their home."

Yolanda W on April 2025

iRiverdale Construction, Inc. is one of New York's elite general contractors, specializing in a diverse range of residential and commercial projects. As a family-owned and operated business with over a decade of experience, we are recognized as masters in our field. Whether you need a concept for your project or want to bring your vision to life, we create stunning works of art tailored to your needs. No matter the size or scope, we apply our unique skill set to ensure your project's success, treating your property with the same care and attention we give our own. Our satisfied repeat customers consistently return to us for new projects, and we are always eager to welcome new clients. Contact us today to schedule an initial consultation and discuss how we can help turn your project into a reality.

"I hired Riverdale construction through a colleague of mine she had worked on on her home and she said this company that is owned by Raquel Diamond is a smart skilled and professional and friendly her team transformed my full basement with adding columns with opening walls for more space. Including moving my bathroom and my laundry room The project manager Jay kept me informed throughout the whole process , always available to answer questions,I felt like they were really listening to our needs.They worked efficiently and stayed on track no delays or unexpected setbacks.
The crew was polite and respectful They cleaned up thoroughly after each day Everyone on the team seemed highly skilled.They went above and beyond toaddress any issues They were very accommodating to our needs. They followed up after the project was completed to ensure I was completely happy . I would recommend I Riverdale Construction and Raquel Diamond to anyone who wants to remodel their home."

Yolanda W on April 2025



American Home and Design, Inc.
47 Chestnut Avenue
5.00(
23
)
Approved Pro
American Home and Design, Inc.
47 Chestnut Avenue
5.00(
23
)
Approved Pro
Customers say: Quality work
25 years of experience
Free onsite estimate

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade! We will always do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business! Call us anytime!

"He has been fantastic!"

Chris P on June 2020

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade! We will always do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business! Call us anytime!

"He has been fantastic!"

Chris P on June 2020


Avatar for Exterior Team Home Services, Inc.
Exterior Team Home Services, Inc.
359 North Ocean Avenue Apt. 1
4.95(
22
)
Approved Pro
Exterior Team Home Services, Inc.
359 North Ocean Avenue Apt. 1
4.95(
22
)
Approved Pro
Customers say: Quality work
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
9 years of experience

Exterior Team Home Services, Inc takes great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer’s needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job. Call Exterior Team Home Services, Inc today!

"Ronald and his Team did an excellent job for a very good price. Very professional. Pointed out some things that needed attention and then took care of it. The workmanship and customer service is better than any other craftman I have ever hired. I will keep Exterior Team Home Service number available to recommend to anyone that asks if "I know someone who...." I trust Exterior Team Home and will use them in the future."

Ed S on September 2023

Exterior Team Home Services, Inc takes great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer’s needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job. Call Exterior Team Home Services, Inc today!

"Ronald and his Team did an excellent job for a very good price. Very professional. Pointed out some things that needed attention and then took care of it. The workmanship and customer service is better than any other craftman I have ever hired. I will keep Exterior Team Home Service number available to recommend to anyone that asks if "I know someone who...." I trust Exterior Team Home and will use them in the future."

Ed S on September 2023


Coastal Carpentry Corp.
110 Woodcut Drive
5.00(
1
)
Approved Pro
Coastal Carpentry Corp.
110 Woodcut Drive
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
7 years of experience

Coastal Carpentry Corp, is committed to excellence in every aspect of our business! We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"They were very easy to work with and I enjoyed their company."

Chad N on July 2021

Coastal Carpentry Corp, is committed to excellence in every aspect of our business! We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"They were very easy to work with and I enjoyed their company."

Chad N on July 2021


Kiwi Restorations, LLC
194 Mill Road
5.00(
2
)
Approved Pro
Kiwi Restorations, LLC
194 Mill Road
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
2 years of experience

We are committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.

"Shane and his crew were fantastic. From our first meeting through completion the renovation was seamless. Great attention to detail, neat, clean and respectful of my house. Finished on time and on budget. Highly recommended."

Mark K on February 2024

We are committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.

"Shane and his crew were fantastic. From our first meeting through completion the renovation was seamless. Great attention to detail, neat, clean and respectful of my house. Finished on time and on budget. Highly recommended."

Mark K on February 2024


Avatar for Granville House Victorians L.L.C.
Granville House Victorians L.L.C.
16 Riverdale Ave
5.00(
1
)
Approved Pro
Granville House Victorians L.L.C.
16 Riverdale Ave
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
20 years of experience

The linkedin site will tell our Story. Clients will take advantage of Granville's in house Design capabilities with CAD. see granvillevictorians.com for examples of our work

"Granville House Victorians L.L.C. is extremely skilled and professional. My Victorian style house came out better than I could have dreamed. Granville took care of everything and they are extremely knowledgeable in what they do."

Jonathan P on January 2023

The linkedin site will tell our Story. Clients will take advantage of Granville's in house Design capabilities with CAD. see granvillevictorians.com for examples of our work

"Granville House Victorians L.L.C. is extremely skilled and professional. My Victorian style house came out better than I could have dreamed. Granville took care of everything and they are extremely knowledgeable in what they do."

Jonathan P on January 2023


Avatar for RJD Construction
RJD Construction
190 Terry Rd
5.00(
1
)
Approved Pro
RJD Construction
190 Terry Rd
5.00(
1
)
Approved Pro
40 years of experience

RJD Construction is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"RJD Construction is hands down one of the most reliable and professional companies I?ve worked with. From start to finish, they were communicative, on time, and detail-oriented. The quality of work exceeded expectations, and their crew was respectful and clean throughout the entire project. Highly recommend RJD for anyone in need of trustworthy and skilled contractors on Long Island!"

Ashley M on June 2025

RJD Construction is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"RJD Construction is hands down one of the most reliable and professional companies I?ve worked with. From start to finish, they were communicative, on time, and detail-oriented. The quality of work exceeded expectations, and their crew was respectful and clean throughout the entire project. Highly recommend RJD for anyone in need of trustworthy and skilled contractors on Long Island!"

Ashley M on June 2025


Thomas O'Neill Custom Design, Inc.
312 Noyac Road
5.00(
2
)
Approved Pro
Thomas O'Neill Custom Design, Inc.
312 Noyac Road
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
23 local quotes requested

At Thomas O'Neill Custom ,we are dedicated to providing you with exceptional customer service. We specialize in getting your projects done in a timely and professional manner. We have been in business for over 20 years and are backed by over 40+ years experience, and are licensed and insured. So call today and set up your free no obligation estimate. We are located in Southampton NY. Thank you.

"."

Homeowner on May 2020

At Thomas O'Neill Custom ,we are dedicated to providing you with exceptional customer service. We specialize in getting your projects done in a timely and professional manner. We have been in business for over 20 years and are backed by over 40+ years experience, and are licensed and insured. So call today and set up your free no obligation estimate. We are located in Southampton NY. Thank you.

"."

Homeowner on May 2020

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FAQs for addition to existing structure building service projects in East Islip, NY

Building an in-law suite takes between two and seven months. Converting an existing basement, attic, or room can be done in about two months. Constructing a new addition or detached suite often takes four to five months for construction, plus one to two months for permits. The bigger the suite, the longer it will take. 

Yes, you can build an in-law suite in your backyard if you meet local building codes and zoning regulations. An in-law suite often occupies 300 to 800 square feet. Be sure to follow size restrictions, utility separations, and entrance requirements. Hiring a qualified contractor ensures you meet all regulatory requirements because they can pull permits, double-check local code, and gather other skilled pros to work on your suite. 

An in-law suite is a self-contained living space attached to—or detached from—your main home. Expect a bedroom, full bath, and a kitchenette or compact living area. The setup gives relatives privacy, doubles as a potential rental, and can lift your property value. To qualify as a legal dwelling, the suite must meet local building codes and zoning rules.

The East Islip, NY homeowners’ guide to addition to existing structure building services
From average costs to expert advice, get all the answers you need to get your job done.
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