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Addition to existing structure builders in Round Hill

Avatar for Best Homes
Best Homes
233 Morrisons Road
4.64(
176
)
Approved Pro
Best Homes
233 Morrisons Road
4.64(
176
)
Approved Pro
Customers say: True professional
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
58 local quotes requested

Here at Best Homes, our company is based on the belief that our customers' needs are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. Please call today for a quote and thank you for doing so.

"We had an exceptional experience with Johnathan, Jeffry, and their team. Their professionalism, friendliness, and expertise stood out from the start to the finish of our basement project. The process was smooth, transparent, and free of surprises, with clear cost and material outlines. We appreciated their flexibility in allowing us to choose different materials and only charging the price difference. When we added more work mid-project, they were accommodating and maintained high-quality workmanship. They provided a wide selection of cabinets, flooring, tiles, mirrors, and bathroom faucets. The project was completed on time and within budget. We are thrilled with the results and plan to work with them again. Everyone who has seen our basement loves it! Overall, we highly recommend their services."

Sammaad S on February 2025

Here at Best Homes, our company is based on the belief that our customers' needs are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. Please call today for a quote and thank you for doing so.

"We had an exceptional experience with Johnathan, Jeffry, and their team. Their professionalism, friendliness, and expertise stood out from the start to the finish of our basement project. The process was smooth, transparent, and free of surprises, with clear cost and material outlines. We appreciated their flexibility in allowing us to choose different materials and only charging the price difference. When we added more work mid-project, they were accommodating and maintained high-quality workmanship. They provided a wide selection of cabinets, flooring, tiles, mirrors, and bathroom faucets. The project was completed on time and within budget. We are thrilled with the results and plan to work with them again. Everyone who has seen our basement loves it! Overall, we highly recommend their services."

Sammaad S on February 2025


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 Eco Power Works
Eco Power Works
12012 English Maple Ln
5.00(
4
)
Approved Pro
Eco Power Works
12012 English Maple Ln
5.00(
4
)
Approved Pro
19 years of experience
Free onsite estimate

A leading construction company in Northern VA focuses on providing optimum quality in various construction services. We take great pride in our work as we have during our 20+ years in business. Thus, you can rest assured, that no matter what construction project we handle, we will be giving nothing but highly professional and expert works. Our galleries collections of photos from previous construction projects can attest to the amount of time, thought, and effort that we put into the services we provide.

"Eco Power Works did a great job on my kitchen and bathroom renovation ! Daryl and John were very patient listening to my ideas. They brought in an architect who was reasonably priced and made suggestions to overall designs which I am so glad they did ! The project from Start to finish was on schedule which O was pleasantly surprised - these guys kept their words and their workers were always on time respectful of my property and time. I like that they always checked with me when they took major steps to double check that everyone was on the same page - they communicated every step of the way and were very careful to to do the job right. I really love the beautiful cabinets and marble countertops which were my dreams. I am so glad I hired these guys - they really did a great job overall - will definitely recommend them to my friends and neighbors !"

Jane _ on April 2025

A leading construction company in Northern VA focuses on providing optimum quality in various construction services. We take great pride in our work as we have during our 20+ years in business. Thus, you can rest assured, that no matter what construction project we handle, we will be giving nothing but highly professional and expert works. Our galleries collections of photos from previous construction projects can attest to the amount of time, thought, and effort that we put into the services we provide.

"Eco Power Works did a great job on my kitchen and bathroom renovation ! Daryl and John were very patient listening to my ideas. They brought in an architect who was reasonably priced and made suggestions to overall designs which I am so glad they did ! The project from Start to finish was on schedule which O was pleasantly surprised - these guys kept their words and their workers were always on time respectful of my property and time. I like that they always checked with me when they took major steps to double check that everyone was on the same page - they communicated every step of the way and were very careful to to do the job right. I really love the beautiful cabinets and marble countertops which were my dreams. I am so glad I hired these guys - they really did a great job overall - will definitely recommend them to my friends and neighbors !"

Jane _ on April 2025


SM Construction LLC
Loacted In
5.00(
15
)
Approved Pro
SM Construction LLC
Loacted In
5.00(
15
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
238 local quotes requested

Here at SM Construction LLC, we take pride in providing quality work at a competitive price. We are professional and punctual and believe in providing 100% customer satisfaction.

"Great job finishing basement. Ahead of schedule, on budget, very flexible with changes along the way. Entire staff was courteous and professional. Great quality ns care in the work."

Joe K on April 2025

Here at SM Construction LLC, we take pride in providing quality work at a competitive price. We are professional and punctual and believe in providing 100% customer satisfaction.

"Great job finishing basement. Ahead of schedule, on budget, very flexible with changes along the way. Entire staff was courteous and professional. Great quality ns care in the work."

Joe K on April 2025


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
38 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 Braemar Cabinetry
Braemar Cabinetry
205 S Union St
5.00(
29
)
Approved Pro
Braemar Cabinetry
205 S Union St
5.00(
29
)
Approved Pro
Customers say: True professional
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
393 local quotes requested

Braemar is the premier destination for custom and semi-custom cabinetry for all areas of your home. We specialize in kitchen and bath design and custom cabinetry. We provide custom cabinets that are tailored to fit your needs, style preferences and budget goals. We also provide kitchen and bath design and cabinetry services for builders, architects and interior designers. We work with a number of different manufacturers including our very own line of cabinetry: Braemar by Hampshire. All of our cabinets are made to order, allowing us to meet every design challenge and style goal. We pride ourselves in our passion for design and enthusiasm in meeting all of our clients needs through detailed and thoughtful design solutions.

"Amazing. Will hire again when we have another project."

Bijal G on November 2019

Braemar is the premier destination for custom and semi-custom cabinetry for all areas of your home. We specialize in kitchen and bath design and custom cabinetry. We provide custom cabinets that are tailored to fit your needs, style preferences and budget goals. We also provide kitchen and bath design and cabinetry services for builders, architects and interior designers. We work with a number of different manufacturers including our very own line of cabinetry: Braemar by Hampshire. All of our cabinets are made to order, allowing us to meet every design challenge and style goal. We pride ourselves in our passion for design and enthusiasm in meeting all of our clients needs through detailed and thoughtful design solutions.

"Amazing. Will hire again when we have another project."

Bijal G on November 2019


Avatar for Willis Builders Inc
Willis Builders Inc
14621 Brougham Way
4.36(
369
)
Approved Pro
Willis Builders Inc
14621 Brougham Way
4.36(
369
)
Approved Pro
Customers say: Quality work
568 local quotes requested
21 years of experience

General contractor servicing Montgomery county and parts of Washington DC. We have had the same Project managers on staff for 9 -17 years. Our newest manager has been with us for 9 years. We believe in high level service over quantity of work. We limit our projects so we can pay more attention to each project. We only take on work that we can effectively handle. We specialize in Additions , bathrooms , kitchens and basements. Our teams are skilled in all aspects of residential construction. For our existing clients we service any project they would like done in their homes. We have developed systems to provide the best communication , quality, and timeliness. We provide free estimates. Hope to hear from you!

"Willis Builders did 2 full baths & kitchen reno + laminate floor install on main level of our modest 3-story T/H (Jan-Apr ‘24). Marcelo was our PM and as many others say, his crew did not disappoint. Willis was neither the highest nor the lowest quote of several but we felt Matt Willis presented the most honest and realistic estimate for our project and he hit that nail on the head. They might say we bothered them with questions; we might say we had to nudge them a few times. We did our homework to help things move along more smoothly & they did their best to accommodate us. We purchased a bunch of stuff before choosing a contractor. No matter what we threw at them, installation was a success which is a testament to the knowledge and capabilities of Marcelo & crew (Horatio, Frankie & “George”). When we were undecided or unsure about a product, Marcelo steered us toward better or more appropriate alternatives. We had no issue, as a few others suggested, with crews leaving things clean at the end of the day. Our T/H is small with limited space for them to work/store materials & equipment. We never felt compromised during 3 months of disruption. (And we never hesitated to leave our home when work was being done.) Is everything perfect? No, there is no such thing as perfection in an almost 40-yr old house reno or any reno for that matter. There were a few glitches as we expected, but uh-ohs and problems that arose were resolved promptly. We waited to post this glowing review of our project to see if any problems showed up, and none did. Until the ceiling in our bedroom collapsed several months later which had absolutely nothing to do with their work. We are so thankful that we had no reservations about sending Matt Willis an SOS for help with our emergency. In fact, we were so confident in his work that we decided to add painting and a carpet upgrade to what has become an almost total house reno. Again, Matt’s estimates were fair and reasonable, such that our confidence in his company allowed us to forgo spending time getting quotes from others. Matt told us repeatedly how good his ‘drywall guy’ was, and he did not exaggerate! Will & sidekick Carlos were fast and fastidious! The carpet install was equally quick and painless. We are so very happy with the results of our sudden and unexpected 2nd Willis project. We're sorry we didn’t get a chance to rave about how thrilled we are with the results of our 1st until now. If you’re considering home improvements, we highly recommend you consider Willis Builders. We’re doubly happy we did!"

John W on November 2024

General contractor servicing Montgomery county and parts of Washington DC. We have had the same Project managers on staff for 9 -17 years. Our newest manager has been with us for 9 years. We believe in high level service over quantity of work. We limit our projects so we can pay more attention to each project. We only take on work that we can effectively handle. We specialize in Additions , bathrooms , kitchens and basements. Our teams are skilled in all aspects of residential construction. For our existing clients we service any project they would like done in their homes. We have developed systems to provide the best communication , quality, and timeliness. We provide free estimates. Hope to hear from you!

"Willis Builders did 2 full baths & kitchen reno + laminate floor install on main level of our modest 3-story T/H (Jan-Apr ‘24). Marcelo was our PM and as many others say, his crew did not disappoint. Willis was neither the highest nor the lowest quote of several but we felt Matt Willis presented the most honest and realistic estimate for our project and he hit that nail on the head. They might say we bothered them with questions; we might say we had to nudge them a few times. We did our homework to help things move along more smoothly & they did their best to accommodate us. We purchased a bunch of stuff before choosing a contractor. No matter what we threw at them, installation was a success which is a testament to the knowledge and capabilities of Marcelo & crew (Horatio, Frankie & “George”). When we were undecided or unsure about a product, Marcelo steered us toward better or more appropriate alternatives. We had no issue, as a few others suggested, with crews leaving things clean at the end of the day. Our T/H is small with limited space for them to work/store materials & equipment. We never felt compromised during 3 months of disruption. (And we never hesitated to leave our home when work was being done.) Is everything perfect? No, there is no such thing as perfection in an almost 40-yr old house reno or any reno for that matter. There were a few glitches as we expected, but uh-ohs and problems that arose were resolved promptly. We waited to post this glowing review of our project to see if any problems showed up, and none did. Until the ceiling in our bedroom collapsed several months later which had absolutely nothing to do with their work. We are so thankful that we had no reservations about sending Matt Willis an SOS for help with our emergency. In fact, we were so confident in his work that we decided to add painting and a carpet upgrade to what has become an almost total house reno. Again, Matt’s estimates were fair and reasonable, such that our confidence in his company allowed us to forgo spending time getting quotes from others. Matt told us repeatedly how good his ‘drywall guy’ was, and he did not exaggerate! Will & sidekick Carlos were fast and fastidious! The carpet install was equally quick and painless. We are so very happy with the results of our sudden and unexpected 2nd Willis project. We're sorry we didn’t get a chance to rave about how thrilled we are with the results of our 1st until now. If you’re considering home improvements, we highly recommend you consider Willis Builders. We’re doubly happy we did!"

John W on November 2024


United Capital Construction
44330 Mercure Circle
5.00(
8
)
Approved Pro
United Capital Construction
44330 Mercure Circle
5.00(
8
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
461 local quotes requested

United Capital Construction offers one of the best qualities and experienced services. We have been in the business since 2004-- from small to big projects, with great references. We specialize in all phases of remodeling for your home, business, bathrooms, kitchens, finishing basements, and more! We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service! Check out all the services we offer below and call -or- click to schedule a free estimate today!

"They did a very high quality job going above and beyond expectations."

Jason T on November 2023

United Capital Construction offers one of the best qualities and experienced services. We have been in the business since 2004-- from small to big projects, with great references. We specialize in all phases of remodeling for your home, business, bathrooms, kitchens, finishing basements, and more! We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service! Check out all the services we offer below and call -or- click to schedule a free estimate today!

"They did a very high quality job going above and beyond expectations."

Jason T on November 2023


Avatar for WaterStone Kitchen and Bath
WaterStone Kitchen and Bath
100 Glenn Drive
5.00(
43
)
Approved Pro
WaterStone Kitchen and Bath
100 Glenn Drive
5.00(
43
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
486 local quotes requested

WaterStone Kitchen and Bath specializes in turn key kitchen and bath remodeling. We have been proudly serving the Northern Virginia area since 2005. We provide a one stop shop from preliminary consulting, through design conception and finally to project completion. One of our specialized designers will combine your vision with years of design experience to create a unique space that exceeds your highest expectations. We offer an extensive line of kitchen and bath products that allow us to meet your design needs on any budget. We operate as an in home service provider only. We don't have a show room, so we can pass our low overhead savings on to our clients. If you are interested in remodeling your kitchen or bath, please contact us for a free in home consultation.

"Jeff and his team (Deanna, Jake, Javier, and Rolando) did an excellent job from start to finish. They worked with us and explained every step of the process, helping us with design decisions and selections. The end product, our new kitchen, is of the highest quality. They made the process very easy and quickly closed out our punch list. We're very excited to have our new, updated kitchen and I would very much recommend WaterStone for future work."

Jim S on January 2023

WaterStone Kitchen and Bath specializes in turn key kitchen and bath remodeling. We have been proudly serving the Northern Virginia area since 2005. We provide a one stop shop from preliminary consulting, through design conception and finally to project completion. One of our specialized designers will combine your vision with years of design experience to create a unique space that exceeds your highest expectations. We offer an extensive line of kitchen and bath products that allow us to meet your design needs on any budget. We operate as an in home service provider only. We don't have a show room, so we can pass our low overhead savings on to our clients. If you are interested in remodeling your kitchen or bath, please contact us for a free in home consultation.

"Jeff and his team (Deanna, Jake, Javier, and Rolando) did an excellent job from start to finish. They worked with us and explained every step of the process, helping us with design decisions and selections. The end product, our new kitchen, is of the highest quality. They made the process very easy and quickly closed out our punch list. We're very excited to have our new, updated kitchen and I would very much recommend WaterStone for future work."

Jim S on January 2023


Avatar for H & C Construction Services LLC
H & C Construction Services LLC
17620 Redland Rd Suite B
4.71(
91
)
Approved Pro
H & C Construction Services LLC
17620 Redland Rd Suite B
4.71(
91
)
Approved Pro
Customers say: Quality work
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
534 local quotes requested

H&C Construction, Design & Build is your ideal partner for home transformation. We specialize in kitchen and bathroom remodels, ensuring that every detail, from planning to execution, is handled with precision. Trust us to create spaces that reflect your style and needs, enhancing the functionality and aesthetics of your home.

"Did a great job. Repaired/replaced rotted wood on front porch. Would use again if needed."

MH T on March 2025

H&C Construction, Design & Build is your ideal partner for home transformation. We specialize in kitchen and bathroom remodels, ensuring that every detail, from planning to execution, is handled with precision. Trust us to create spaces that reflect your style and needs, enhancing the functionality and aesthetics of your home.

"Did a great job. Repaired/replaced rotted wood on front porch. Would use again if needed."

MH T on March 2025

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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
From average costs to expert advice, get all the answers you need to get your job done.
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