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Addition to existing structure builders in Mattituck

Avatar for Hampton Design and Build
Hampton Design and Build
P.O. Box 308
4.81(
26
)
Approved Pro
Hampton Design and Build
P.O. Box 308
4.81(
26
)
Approved Pro
Customers say: Quick response
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
23 years of experience

Hampton Design and Build is pleased to be partnering with HomeAdvisor to offer our full service addition, design and remodeling services to the greater East End area. We have been in business for over 30 years and we pride ourselves in our exemplary service, our craftsmanship and attention to detail. Being a full service contracting company there is no need to go anywhere else. Please call for a free estimate.

"We have done projects with different contractors, but putting an addition on to our house was by far the biggest project we had ever done. We were terrified of its breadth and complexityâ particularly as concerned making the house comfortable for my elderly parents and more accessible for my son, who uses a wheelchair. We met with several contractors and chose HDB both because their bid was more reasonable and because we had a gut feeling of trust that, fortunately for us, never ebbed throughout the process. Choosing HDB was the best decision we have ever made in the 10 years we have owned our house, and we will continue to solicit their expertise for any future work. At every step of the process they demonstrated their authenticity, integrity, empathy and expertise. For questions we had about anything, big or small, we received a response within a day. We added two and half rooms and bathrooms to ones side of the house. Based on his vast experience in our area, Dale had important, smart suggestions for modest but powerful improvements elsewhere in the house that would not have occurred to me but proved to be invaluable--and increased the value of our home dramatically. He navigated town permit issues. Cost was very reasonable and if there were any questions, he was open to discussing and adjusting. Diane had superb design instincts, which saved us from hiring another professional, and as part of the fee she sent wise suggestions for vanities, light fixtures, paint colors, rugs and more; and then ordered the items directly. Both obviously cared about us and the project and made everything as easy as possible for us. Most projects we had done previously had faltered at the end, with smaller punch list items; but as usual, Diane and Dale were responsive til the final t was crossed and I dotted. HDB is a rare company with skill and expertise but also with a passion for their work and a spirit of kindness and concern for their clients that made a house addition â something we dreaded--actually fun. Thanks HDB!"

Harriet B on November 2023

Hampton Design and Build is pleased to be partnering with HomeAdvisor to offer our full service addition, design and remodeling services to the greater East End area. We have been in business for over 30 years and we pride ourselves in our exemplary service, our craftsmanship and attention to detail. Being a full service contracting company there is no need to go anywhere else. Please call for a free estimate.

"We have done projects with different contractors, but putting an addition on to our house was by far the biggest project we had ever done. We were terrified of its breadth and complexityâ particularly as concerned making the house comfortable for my elderly parents and more accessible for my son, who uses a wheelchair. We met with several contractors and chose HDB both because their bid was more reasonable and because we had a gut feeling of trust that, fortunately for us, never ebbed throughout the process. Choosing HDB was the best decision we have ever made in the 10 years we have owned our house, and we will continue to solicit their expertise for any future work. At every step of the process they demonstrated their authenticity, integrity, empathy and expertise. For questions we had about anything, big or small, we received a response within a day. We added two and half rooms and bathrooms to ones side of the house. Based on his vast experience in our area, Dale had important, smart suggestions for modest but powerful improvements elsewhere in the house that would not have occurred to me but proved to be invaluable--and increased the value of our home dramatically. He navigated town permit issues. Cost was very reasonable and if there were any questions, he was open to discussing and adjusting. Diane had superb design instincts, which saved us from hiring another professional, and as part of the fee she sent wise suggestions for vanities, light fixtures, paint colors, rugs and more; and then ordered the items directly. Both obviously cared about us and the project and made everything as easy as possible for us. Most projects we had done previously had faltered at the end, with smaller punch list items; but as usual, Diane and Dale were responsive til the final t was crossed and I dotted. HDB is a rare company with skill and expertise but also with a passion for their work and a spirit of kindness and concern for their clients that made a house addition â something we dreaded--actually fun. Thanks HDB!"

Harriet B on November 2023


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


Avatar for Webb Builders
Webb Builders
PO Box 744
5.00(
4
)
Approved Pro
Webb Builders
PO Box 744
5.00(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
12 local quotes requested

Webb Builders, Inc. and our subsidiary, Webbstar Networking & Technology Solutions 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.

"Dean was extremely professional and worked within my budget. I would highly recommend Dean for future projects."

Antoinette A on March 2021

Webb Builders, Inc. and our subsidiary, Webbstar Networking & Technology Solutions 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.

"Dean was extremely professional and worked within my budget. I would highly recommend Dean for future projects."

Antoinette A on March 2021


MRJ Industries, Ltd.
27 Quail Run
4.29(
7
)
Approved Pro
MRJ Industries, Ltd.
27 Quail Run
4.29(
7
)
Approved Pro
Customers say: Quick response
39 years of experience
Free onsite estimate

We are dedicated to providing our clients with the very best in general contracting, from electrical to decks, siding, roofing, remodels, and renovations. With over 30 years of experience, we take an enormous amount of pride in the attention of detail, put into each of the projects we contract. We are known for our quality work, and the integrity of our business practices. We look forward to building long term relationships with our clients, and guarantee your satisfaction. Call today for a quote! As an owner operator I am personally involved with every project. John

"John was great initially - getting there and tackling the immediate problem and answering my calls. We had a short in the electrical heating fan/motor in the floor that was potentially dangerous and could have caused a fire so he replaced the breaker and rewired the fan/motor. However, when he left we noticed that the fan was not running in the box and he told us to detach the wires which I felt was risky and also meant the problem was not fixed. He said he would come back the following Monday to inspect the rest of the wires underneath the house and he never did. He was also supposed to send me a photo of the burned wires, a work order/receipt for my files, and never did. I texted him about Monday and about replacing the fan/motor - either to let us what it was called and we would replace it ourselves or give us the cost of replacing one or all 3 boxes. He never responded so we still have a heating system that is not fixed and perhaps dangerous if only running on two fan motors ."

Gillian d on November 2018

We are dedicated to providing our clients with the very best in general contracting, from electrical to decks, siding, roofing, remodels, and renovations. With over 30 years of experience, we take an enormous amount of pride in the attention of detail, put into each of the projects we contract. We are known for our quality work, and the integrity of our business practices. We look forward to building long term relationships with our clients, and guarantee your satisfaction. Call today for a quote! As an owner operator I am personally involved with every project. John

"John was great initially - getting there and tackling the immediate problem and answering my calls. We had a short in the electrical heating fan/motor in the floor that was potentially dangerous and could have caused a fire so he replaced the breaker and rewired the fan/motor. However, when he left we noticed that the fan was not running in the box and he told us to detach the wires which I felt was risky and also meant the problem was not fixed. He said he would come back the following Monday to inspect the rest of the wires underneath the house and he never did. He was also supposed to send me a photo of the burned wires, a work order/receipt for my files, and never did. I texted him about Monday and about replacing the fan/motor - either to let us what it was called and we would replace it ourselves or give us the cost of replacing one or all 3 boxes. He never responded so we still have a heating system that is not fixed and perhaps dangerous if only running on two fan motors ."

Gillian d on November 2018


KG Home Improvement
29 Rabbit Run
5.00(
1
)
Approved Pro
KG Home Improvement
29 Rabbit Run
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
21 years of experience

Great work at great price! A fresh coat of paint or stain can bring new life to rooms, add curb appeal to homes and commercial buildings, and help protect your investment for years to come. We are happy to bid on all types of painting in the Riverhead area. We will meet with you, at your convenience, and provide you with a free, written, detailed estimate – no surprise charges added after the fact. Locally owned and operated, we’re a small company with big capabilities, including interior painting, exterior painting, commercial painting, deck finishing, and interior design.

"They did a great job, and stayed on schedule. There bid was very competitive. Would hire again."

Charles S on April 2020

Great work at great price! A fresh coat of paint or stain can bring new life to rooms, add curb appeal to homes and commercial buildings, and help protect your investment for years to come. We are happy to bid on all types of painting in the Riverhead area. We will meet with you, at your convenience, and provide you with a free, written, detailed estimate – no surprise charges added after the fact. Locally owned and operated, we’re a small company with big capabilities, including interior painting, exterior painting, commercial painting, deck finishing, and interior design.

"They did a great job, and stayed on schedule. There bid was very competitive. Would hire again."

Charles S on April 2020


Avatar for FD Building Co.
FD Building Co.
185 Montauk Highway
4.80(
17
)
Approved Pro
FD Building Co.
185 Montauk Highway
4.80(
17
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
16 years of experience

FD Building Co., has provided high quality work and friendly customer service for over 20 years. We get the job done efficiently and meticulously. We a full construction crew and maintenance program to keep your investment meticulously maintained. Visit or call us today!

"Great company to work with. Not cheap but they do good work and they have nice people."

Holly K on April 2022

FD Building Co., has provided high quality work and friendly customer service for over 20 years. We get the job done efficiently and meticulously. We a full construction crew and maintenance program to keep your investment meticulously maintained. Visit or call us today!

"Great company to work with. Not cheap but they do good work and they have nice people."

Holly K on April 2022


Design Development Construction Services, LLC
900 South 2nd St Suite #5
4.86(
12
)
Approved Pro
Design Development Construction Services, LLC
900 South 2nd St Suite #5
4.86(
12
)
Approved Pro
Customers say: Quality work
51 years of experience
Free onsite estimate

Hiring a general contractor is the first step in taking control of your home improvement project. Having an industry professional like Design Development Construction Services, LLC coordinate and manage all aspects of your project means fewer delays, tighter quality control and a more successful outcome. All of these contribute to a greater return on your investment. We have been in business since 1974 and would like the opportunity to speak with you about your home improvement needs.

"Very experienced company with an amazing wood working facility for custom projects. Excellent communication and customer service."

Liat A on July 2021

Hiring a general contractor is the first step in taking control of your home improvement project. Having an industry professional like Design Development Construction Services, LLC coordinate and manage all aspects of your project means fewer delays, tighter quality control and a more successful outcome. All of these contribute to a greater return on your investment. We have been in business since 1974 and would like the opportunity to speak with you about your home improvement needs.

"Very experienced company with an amazing wood working facility for custom projects. Excellent communication and customer service."

Liat A on July 2021


Avatar for Two Stories Building Co
Two Stories Building Co
74365 Main Rd STE 1
5.00(
3
)
Approved Pro
Two Stories Building Co
74365 Main Rd STE 1
5.00(
3
)
Approved Pro
Customers say: Quick response
11 years of experience
Free onsite estimate

At Two Stories Building Co., your home isn’t just another project—it’s where your life unfolds, your style takes shape, and your vision comes to life. Since 2014, you’ve trusted us to transform spaces with precision, care, and craftsmanship that stands the test of time. We blend modern construction techniques with high-quality, sustainable materials to create homes that are as functional as they are beautiful. You deserve a process that’s seamless, transparent, and free of unnecessary stress. That’s why we keep you informed at every step, ensuring your ideas are heard, your expectations are exceeded, and your investment is respected. Whether you're planning a full-scale remodel or building from the ground up, your goals guide every decision, and your satisfaction drives everything we do. More than just builders, we’re your partners—committed to making your home everything you’ve envisioned and more.

"The work that was done was exceptional! It was exactly what I wanted and done with great craftsmanship. They were easy to talk to and had great communication as far as timelines and cost. I would highly recommend them and would have them do any work needed again without question. Totally professional!"

Frances T on March 2025

At Two Stories Building Co., your home isn’t just another project—it’s where your life unfolds, your style takes shape, and your vision comes to life. Since 2014, you’ve trusted us to transform spaces with precision, care, and craftsmanship that stands the test of time. We blend modern construction techniques with high-quality, sustainable materials to create homes that are as functional as they are beautiful. You deserve a process that’s seamless, transparent, and free of unnecessary stress. That’s why we keep you informed at every step, ensuring your ideas are heard, your expectations are exceeded, and your investment is respected. Whether you're planning a full-scale remodel or building from the ground up, your goals guide every decision, and your satisfaction drives everything we do. More than just builders, we’re your partners—committed to making your home everything you’ve envisioned and more.

"The work that was done was exceptional! It was exactly what I wanted and done with great craftsmanship. They were easy to talk to and had great communication as far as timelines and cost. I would highly recommend them and would have them do any work needed again without question. Totally professional!"

Frances T on March 2025


Avatar for Enterprise Global Group
Enterprise Global Group
PO Box 2746
4.97(
18
)
Approved Pro
Enterprise Global Group
PO Box 2746
4.97(
18
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
9 years of experience

With over 20 years experience in the construction industry, Gomez Multi-Service is your industry expert in Suffolk county. We pride ourselves on our extreme professionalism, quality of work, and attention to detail. Our customer satisfaction guarantee will assure you we will not leave your property until you are completely satisfied with our work. As a locally owned and operated business you can trust that we will treat your home as we would treat our own. Give us a call today we look forward to working with you!

"I am planning to use them to replace some doors."

Lance A on September 2023

With over 20 years experience in the construction industry, Gomez Multi-Service is your industry expert in Suffolk county. We pride ourselves on our extreme professionalism, quality of work, and attention to detail. Our customer satisfaction guarantee will assure you we will not leave your property until you are completely satisfied with our work. As a locally owned and operated business you can trust that we will treat your home as we would treat our own. Give us a call today we look forward to working with you!

"I am planning to use them to replace some doors."

Lance A on September 2023


Avatar for Andrew Murphy & Company
Andrew Murphy & Company
PO BOX 501
5.00(
3
)
Approved Pro
Andrew Murphy & Company
PO BOX 501
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
4 years of experience

Build. Better. We are a custom builder that prides ourselves on exceeding expectations and working with our clients and architects in a Team Environment to bring the vision of your new home to life. It's not just the ability to build to the fit and finish you expect, it's managing the people, time, materials and cost daily to ensure a quality product and a home finished on time, every time.

"Uncompromising quality and attention to detail. Fantastic subs who were true artisans. Built a 3600 square foot house totally on schedule in just under a year. There was nothing in this construction project that had to be re-done. The appropriate questions were always asked before work proceeded. Our buildung site was also kept clean and orderly. Andrew is a master of scheduling ans organization so work progressed with very few timing glitches."

Deborah L on December 2024

Build. Better. We are a custom builder that prides ourselves on exceeding expectations and working with our clients and architects in a Team Environment to bring the vision of your new home to life. It's not just the ability to build to the fit and finish you expect, it's managing the people, time, materials and cost daily to ensure a quality product and a home finished on time, every time.

"Uncompromising quality and attention to detail. Fantastic subs who were true artisans. Built a 3600 square foot house totally on schedule in just under a year. There was nothing in this construction project that had to be re-done. The appropriate questions were always asked before work proceeded. Our buildung site was also kept clean and orderly. Andrew is a master of scheduling ans organization so work progressed with very few timing glitches."

Deborah L on December 2024

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Addition to existing structure building services FAQs

How far you can push a room depends on the structure you choose. A cantilevered bump-out can extend 24 inches before building codes require its own footing or foundation. Anything longer needs engineered support and a permit. Check local codes or consult with a structural professional before finalizing plans to ensure your design remains safe and compliant.

Most bump-outs are completed within one to four weeks, even with minimal electrical, plumbing, or HVAC work. Their compact size means less demolition, simpler inspections, and fewer weather-related delays compared to a full-scale addition. Your contractor can provide a more precise timeline once they have determined the scope, materials, and permit schedule, but plan on having the extra square footage ready in approximately a month.

The homeowners guide to addition to existing structure building services
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