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Addition to existing structure builders in Washington DC

R & A Contractors Group Inc.
7826 Eastern Avenue Northwest, Suite 515
5.00(
3
)
Approved Pro
R & A Contractors Group Inc.
7826 Eastern Avenue Northwest, Suite 515
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
20 years of experience

R & A Contractors Group Inc. 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 customer's interests, and make their concerns the basis of our business.

"R&A Contractors Group, Inc., is a great company to work with. They are on time, efficient, and upfront with pricing."

Daren D on November 2022

R & A Contractors Group Inc. 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 customer's interests, and make their concerns the basis of our business.

"R&A Contractors Group, Inc., is a great company to work with. They are on time, efficient, and upfront with pricing."

Daren D on November 2022


Avatar for ACS Construction
ACS Construction
6089 Majors Lane, Suite 10
5.00(
4
)
Approved Pro
ACS Construction
6089 Majors Lane, Suite 10
5.00(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
25 years of experience

Trust ACS Construction in Washington DC NW. to handle all your new construction and remodeling projects. We have earned a reputation for excellence, thanks to our dedicated team of employees and associates, as well as our huge network of vendors. Despite the high level of competition in the industry , we have managed to rise above and deliver first-rate services every time. We are not only HomeAdvisor members, but you can also find us on BBB, Houzz, NARI, NKBA. More than just arriving at your location on time, we also make it a point to finish the job before the deadline. We will even extend hours if the situation calls for it. Unlike other companies, we thoroughly explain the entire process so you know what is happening. We will constantly update you with the status of completion and will not impose something that you do not need.

"I hired German to renovate our basement (utility room, laundry room, storage...), including a complete overhaul of plumbing and wiring. I was extremely pleased with the quality of work, the organization of various activities, the price asked and the follow-up. By employing skilled and efficient workers licensed for plumbing (water and gas), electrical and carpentry/drywall the coordination of the various trades was limited to the strict minimum. I would not hesitate to recommend German for similar renovation/extension projects."

Alain L on October 2023

Trust ACS Construction in Washington DC NW. to handle all your new construction and remodeling projects. We have earned a reputation for excellence, thanks to our dedicated team of employees and associates, as well as our huge network of vendors. Despite the high level of competition in the industry , we have managed to rise above and deliver first-rate services every time. We are not only HomeAdvisor members, but you can also find us on BBB, Houzz, NARI, NKBA. More than just arriving at your location on time, we also make it a point to finish the job before the deadline. We will even extend hours if the situation calls for it. Unlike other companies, we thoroughly explain the entire process so you know what is happening. We will constantly update you with the status of completion and will not impose something that you do not need.

"I hired German to renovate our basement (utility room, laundry room, storage...), including a complete overhaul of plumbing and wiring. I was extremely pleased with the quality of work, the organization of various activities, the price asked and the follow-up. By employing skilled and efficient workers licensed for plumbing (water and gas), electrical and carpentry/drywall the coordination of the various trades was limited to the strict minimum. I would not hesitate to recommend German for similar renovation/extension projects."

Alain L on October 2023


Avatar for Alltecs, LLC
Alltecs, LLC
1800 Diagonal Rd Ste 600
3.96(
13
)
Approved Pro
Alltecs, LLC
1800 Diagonal Rd Ste 600
3.96(
13
)
Approved Pro
Customers say: Terrific value
19 local quotes requested
10 years of experience

At Alltecs, we are a leading minority-owned construction firm dedicated to delivering exceptional residential and commercial construction services throughout the DC area. With a strong commitment to professionalism, integrity, quality, and service, we have established ourselves as a trusted name in the industry. Our company was founded with a vision to provide top-notch construction solutions that exceed our clients' expectations. We understand that every project is unique, and our team of skilled professionals brings a wealth of expertise and experience to every endeavor. From concept to completion, we strive for excellence and ensure that each project is executed with meticulous attention to detail.

"I purchased a property that needed a full remodel. I contacted Alltecs and they were very accommodating & professional. My home is so beautiful & luxurious. Few delays due to permitting & material delivery, however Alltecs always communicated during the process. Although, the delays were a frustrating process Alltecs pulled through & I’m so happy with the final results! Thanks Again! I would definitely recommend this company."

Nakita G on January 2022

At Alltecs, we are a leading minority-owned construction firm dedicated to delivering exceptional residential and commercial construction services throughout the DC area. With a strong commitment to professionalism, integrity, quality, and service, we have established ourselves as a trusted name in the industry. Our company was founded with a vision to provide top-notch construction solutions that exceed our clients' expectations. We understand that every project is unique, and our team of skilled professionals brings a wealth of expertise and experience to every endeavor. From concept to completion, we strive for excellence and ensure that each project is executed with meticulous attention to detail.

"I purchased a property that needed a full remodel. I contacted Alltecs and they were very accommodating & professional. My home is so beautiful & luxurious. Few delays due to permitting & material delivery, however Alltecs always communicated during the process. Although, the delays were a frustrating process Alltecs pulled through & I’m so happy with the final results! Thanks Again! I would definitely recommend this company."

Nakita G on January 2022


Avatar for 3DF, LLC
3DF, LLC
11630 Mediterranean Ct
4.63(
8
)
Approved Pro
3DF, LLC
11630 Mediterranean Ct
4.63(
8
)
Approved Pro
Customers say: True professional
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
40 years of experience

3DF LLC is a locally owned and operated company serving the Reston, VA area and surrounding communities. 3DF, LLC is a full service design & builder of your dream home and living environment. We can help expand your existing structure for you and your family to enjoy for years. Professional craftsmanship, reasonable rates, and friendly customer service. Call us now!

"Could not be happier with Jim's work. Remodeled master bath, kitchen, replaced front door, plus several other smaller tasks. Easy to work with. Has a talented eye for style and design. Kept me informed throughout the process. Has experience with the design board in my town (Reston). Never up-charged. I've recommended him to several neighbors already."

Brian B on August 2024

3DF LLC is a locally owned and operated company serving the Reston, VA area and surrounding communities. 3DF, LLC is a full service design & builder of your dream home and living environment. We can help expand your existing structure for you and your family to enjoy for years. Professional craftsmanship, reasonable rates, and friendly customer service. Call us now!

"Could not be happier with Jim's work. Remodeled master bath, kitchen, replaced front door, plus several other smaller tasks. Easy to work with. Has a talented eye for style and design. Kept me informed throughout the process. Has experience with the design board in my town (Reston). Never up-charged. I've recommended him to several neighbors already."

Brian B on August 2024


Avatar for Kozan Construction, LLC
Kozan Construction, LLC
4584 Cornell Drive
4.70(
23
)
Approved Pro
Kozan Construction, LLC
4584 Cornell Drive
4.70(
23
)
Approved Pro
Customers say: True professional
40 years of experience
Free onsite estimate

We have over 10 years of experience in the business. Here at Kozan Construction, LLC, we pride our company on reliability, great communication, integrity and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"I want a new look of my kitchen, and they were amazing work done. I just love the result. Great service.."

Nikki P on April 2024

We have over 10 years of experience in the business. Here at Kozan Construction, LLC, we pride our company on reliability, great communication, integrity and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"I want a new look of my kitchen, and they were amazing work done. I just love the result. Great service.."

Nikki P on April 2024


Avatar for All Renovations Inc
All Renovations Inc
6920B Braddock Rd
4.71(
116
)
Approved Pro
All Renovations Inc
6920B Braddock Rd
4.71(
116
)
Approved Pro
Customers say: Quick response
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
39 local quotes requested

All Renovations was started by a local graduate of George Washington University. We are fully licensed in all trade work including building, electrical and plumbing . We have always put our customers first in delivering what we promise without any gimmicks. The reputation of our company is proven through our satisfactory track record including winning the highly coveted Angie’s List Super Service Award and being selected as a Best Pick Report contractor on numerous occasions. The staff at our company values your time with prompt on site visits, quick turnaround in providing cost estimates, and a responsive attitude until job completion. We can assure you that our pricing and written warranty provides value in your investment when compared with other professionally licensed contractors. Due to our staffing requirements we are only able to take on jobs $10k or higher.

"I am giving All Renovations 5 stars for the basement renovation in large part because of Adrian’s excellent craftsmanship and attention to detail. Our job was pretty extensive. It included moving support columns, demo and rebuild exterior stairway, adding a full bath, extending the finished/framed portion of the basement, moving the circuit-breaker panel, and re-doing our half-bath. The job took 6 months, which was about twice as long as we expected. Omar was always very responsive and provided good feedback. Adrian is very good at explaining things and soliciting your input when options/alternatives exist. He definitely does not take short-cuts if quality would suffer. He is also very considerate/careful inside your home and cleans-up after himself. Our $102k project ballooned to $125k, mostly due to nice to have add-ons and unforeseen issues. But there were several items I feel should have been caught at the contract onset. E.g. the need for a floor drain ($900), considering that we were getting rid of the utility sink basin. There was also an extra $4k to replace the drywall in the half bath since the existing paint was too textured (sponge) to paint over. But we were very pleased with the outcome and would definitely recommend All Renovations."

Shane G on March 2025

All Renovations was started by a local graduate of George Washington University. We are fully licensed in all trade work including building, electrical and plumbing . We have always put our customers first in delivering what we promise without any gimmicks. The reputation of our company is proven through our satisfactory track record including winning the highly coveted Angie’s List Super Service Award and being selected as a Best Pick Report contractor on numerous occasions. The staff at our company values your time with prompt on site visits, quick turnaround in providing cost estimates, and a responsive attitude until job completion. We can assure you that our pricing and written warranty provides value in your investment when compared with other professionally licensed contractors. Due to our staffing requirements we are only able to take on jobs $10k or higher.

"I am giving All Renovations 5 stars for the basement renovation in large part because of Adrian’s excellent craftsmanship and attention to detail. Our job was pretty extensive. It included moving support columns, demo and rebuild exterior stairway, adding a full bath, extending the finished/framed portion of the basement, moving the circuit-breaker panel, and re-doing our half-bath. The job took 6 months, which was about twice as long as we expected. Omar was always very responsive and provided good feedback. Adrian is very good at explaining things and soliciting your input when options/alternatives exist. He definitely does not take short-cuts if quality would suffer. He is also very considerate/careful inside your home and cleans-up after himself. Our $102k project ballooned to $125k, mostly due to nice to have add-ons and unforeseen issues. But there were several items I feel should have been caught at the contract onset. E.g. the need for a floor drain ($900), considering that we were getting rid of the utility sink basin. There was also an extra $4k to replace the drywall in the half bath since the existing paint was too textured (sponge) to paint over. But we were very pleased with the outcome and would definitely recommend All Renovations."

Shane G on March 2025


Avatar for Betterliving Sunrooms Of The Capital Area
Betterliving Sunrooms Of The Capital Area
123 Main Str
4.75(
53
)
Approved Pro
Betterliving Sunrooms Of The Capital Area
123 Main Str
4.75(
53
)
Approved Pro
Customers say: Quality work
Recommended by 94% of Angi customers
Recommended by 94% of HomeAdvisor customers
912 local quotes requested

Betterliving sunroom of the Capital area is sub division of Deck Soldier - family own business, over 14 years we spetialise in Deck building , restoration and screen porch constractions. December 2023 is time when we get opportunity to be come dealer for one of the best Sunroom manufactory -Betterliving sunrooms. Beginning of 2024 was education time. We spent 2 weeks with crew leaders on factory in PA - learning new materials and installation process. Another 2 weeks our sales team learned history of 70 years company and saw how every detail of sunroom is made, learn why Betterliving Sunrooms is best quality sunrooms on market. We proud that we build over 30 Sunrooms and screen porches in 2024 and all our customers happy with their final rooms. We sustain our business on quality and integrity. We look forward to earning your business -sunrooms (3 or 4 season , vinyl or aluminum) -screen rooms -porches -deck building -deck remodeling -deck restoration( washing, staining) -paver patio/retaining walls

"Deck Soldier (aka Betterliving) did a fantastic job of powerwashing and then sealing my deck, installing new handrails, and staining the swingset in the yard. Very pleased with their work and their professionalism."

Andrew H on October 2024

Betterliving sunroom of the Capital area is sub division of Deck Soldier - family own business, over 14 years we spetialise in Deck building , restoration and screen porch constractions. December 2023 is time when we get opportunity to be come dealer for one of the best Sunroom manufactory -Betterliving sunrooms. Beginning of 2024 was education time. We spent 2 weeks with crew leaders on factory in PA - learning new materials and installation process. Another 2 weeks our sales team learned history of 70 years company and saw how every detail of sunroom is made, learn why Betterliving Sunrooms is best quality sunrooms on market. We proud that we build over 30 Sunrooms and screen porches in 2024 and all our customers happy with their final rooms. We sustain our business on quality and integrity. We look forward to earning your business -sunrooms (3 or 4 season , vinyl or aluminum) -screen rooms -porches -deck building -deck remodeling -deck restoration( washing, staining) -paver patio/retaining walls

"Deck Soldier (aka Betterliving) did a fantastic job of powerwashing and then sealing my deck, installing new handrails, and staining the swingset in the yard. Very pleased with their work and their professionalism."

Andrew H on October 2024


Avatar for BasementRemodeling.com
BasementRemodeling.com
1680 E Gude Dr
4.74(
253
)
Approved Pro
BasementRemodeling.com
1680 E Gude Dr
4.74(
253
)
Approved Pro
Customers say: Quality work
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
311 local quotes requested

BasementRemodeling.com / Basement Masters - licensed and insured, award winning Basement Remodeling and Finishing company. Highest rated basement renovation contractor in Maryland. Finished Basements are our specialty. We specialize in custom basement remodeling and finishing and other large-scale remodels. We offer free in home and over-the-phone estimate and consultation. Here at BasementRemodeling.com we believe that QUALITY AND EXCEPTIONAL CRAFTSMANSHIP must always come along with AFFORDABILITY. keywords: finished basement basements remodeling.

"Job was performed in a timely manner. Great communication throughout project. Site kept clean during construction."

Erin K on October 2024

BasementRemodeling.com / Basement Masters - licensed and insured, award winning Basement Remodeling and Finishing company. Highest rated basement renovation contractor in Maryland. Finished Basements are our specialty. We specialize in custom basement remodeling and finishing and other large-scale remodels. We offer free in home and over-the-phone estimate and consultation. Here at BasementRemodeling.com we believe that QUALITY AND EXCEPTIONAL CRAFTSMANSHIP must always come along with AFFORDABILITY. keywords: finished basement basements remodeling.

"Job was performed in a timely manner. Great communication throughout project. Site kept clean during construction."

Erin K on October 2024


Avatar for American Deck & Patio
American Deck & Patio
10319 Westlake Dr
4.60(
211
)
Approved Pro
American Deck & Patio
10319 Westlake Dr
4.60(
211
)
Approved Pro
Customers say: Quality work
422 local quotes requested
36 years of experience

We design and build custom outdoor living spaces in natural wood, low maintenance materials, natural stone, and concrete pavers. We're fully licensed and insured. We have been in business since 1989 and have thousands of satisfied customers throughout the DC Metro Area. We are A+ Rated with the BBB and have won Angie's List Super Service Award for 6 years in a row. We do not offer staining, sealing, and cleaning services.

"Very difficult to work with, we went weeks or more without answers to our emails at points. We ran into some zoning issues, which I later learned are typical in DC, and which AMdeck didn't mention before stating a potential completion date. As a result, they suggested we use a "postcard" permit, which is an illegal way of showing a fake in the window, so that our neighbors would be less likely to request a work shutdown. We didn't want to do that, requested the drawings and applications from the owners so that we could do it the legit way. They ignored us until we let them know we wanted to end our contract with them. They then charged us $2K."

Geoffrey L on September 2024

We design and build custom outdoor living spaces in natural wood, low maintenance materials, natural stone, and concrete pavers. We're fully licensed and insured. We have been in business since 1989 and have thousands of satisfied customers throughout the DC Metro Area. We are A+ Rated with the BBB and have won Angie's List Super Service Award for 6 years in a row. We do not offer staining, sealing, and cleaning services.

"Very difficult to work with, we went weeks or more without answers to our emails at points. We ran into some zoning issues, which I later learned are typical in DC, and which AMdeck didn't mention before stating a potential completion date. As a result, they suggested we use a "postcard" permit, which is an illegal way of showing a fake in the window, so that our neighbors would be less likely to request a work shutdown. We didn't want to do that, requested the drawings and applications from the owners so that we could do it the legit way. They ignored us until we let them know we wanted to end our contract with them. They then charged us $2K."

Geoffrey L on September 2024


Blue Rock Remodeling Inc
6177 Executive Blvd
New on HomeAdvisorNew on Angi
Approved Pro
Blue Rock Remodeling Inc
6177 Executive Blvd
New on AngiNew on HomeAdvisor
Approved Pro
82 local quotes requested
...
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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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