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Addition to existing structure builders in O Fallon

Matt Hawkins Construction
17401 Koch Creek Road
5.00(
2
)
Approved Pro
Matt Hawkins Construction
17401 Koch Creek Road
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
8 years of experience

With several years experience, we work hard to bring each customer the best possible service and quality available. We look forward to working with you on your next project. We welcome your questions and thank you for your interest.

"High quality work, very responsive, good guys."

Mike S on March 2020

With several years experience, we work hard to bring each customer the best possible service and quality available. We look forward to working with you on your next project. We welcome your questions and thank you for your interest.

"High quality work, very responsive, good guys."

Mike S on March 2020


Avatar for Weaver Commercial & Home Improvements, LLC
Weaver Commercial & Home Improvements, LLC
7827 Town Square Avenue Suite 104
4.13(
16
)
Approved Pro
Weaver Commercial & Home Improvements, LLC
7827 Town Square Avenue Suite 104
4.13(
16
)
Approved Pro
Customers say: Terrific value
14 local quotes requested
38 years of experience

Nothing improves the value of your home more than professional updates. At Weaver Commercial and Home Improvements we are a family owned and operated company that provides a wide range of service from kitchen, bath and basement remodels to complete decking installs, room additions and outdoor living spaces. We will customize your home with features to make daily life easier while improving the value of your home. With over 30 years of experience, we bring the quality and service you can trust. Our staff will work closely with you throughout the life cycle of your projects to ensure all of your goals are met. Visa and Mastercard accepted. We also offer financing options from 18 months no interest to fixed rate options for longer payment timelines. Give us a call today!! You won't be disappointed!

"Weaver did very well with our basement finishing. They did get the way we wanted things done, which was a bit unique, but they did miss a few things, like not understand we were going to take care of some things that were non-standard ourselves (because they were non-standard.). They also did leave us hanging a little at the end - we still never got our light switch at the end of the stairs hooked back up to the light, nor found out how to change the cam lights, but at some point I just gave up, cause they were kinda done with us after they got their last payment. Generally good to work with, they did have a bit of a time getting workers due to COVID, and there were some small less than desirable messes left. But thatâ  s small compared to the overall work, which was good. So Iâ  m pretty happy overall."

Jamie B on August 2021

Nothing improves the value of your home more than professional updates. At Weaver Commercial and Home Improvements we are a family owned and operated company that provides a wide range of service from kitchen, bath and basement remodels to complete decking installs, room additions and outdoor living spaces. We will customize your home with features to make daily life easier while improving the value of your home. With over 30 years of experience, we bring the quality and service you can trust. Our staff will work closely with you throughout the life cycle of your projects to ensure all of your goals are met. Visa and Mastercard accepted. We also offer financing options from 18 months no interest to fixed rate options for longer payment timelines. Give us a call today!! You won't be disappointed!

"Weaver did very well with our basement finishing. They did get the way we wanted things done, which was a bit unique, but they did miss a few things, like not understand we were going to take care of some things that were non-standard ourselves (because they were non-standard.). They also did leave us hanging a little at the end - we still never got our light switch at the end of the stairs hooked back up to the light, nor found out how to change the cam lights, but at some point I just gave up, cause they were kinda done with us after they got their last payment. Generally good to work with, they did have a bit of a time getting workers due to COVID, and there were some small less than desirable messes left. But thatâ  s small compared to the overall work, which was good. So Iâ  m pretty happy overall."

Jamie B on August 2021


Avatar for McIntosh Construction
McIntosh Construction
948 Nana Ln
5.00(
6
)
Approved Pro
McIntosh Construction
948 Nana Ln
5.00(
6
)
Approved Pro
4 years of experience
Free onsite estimate

At McIntosh Construction , we believe in honesty, integrity, and transparency. We are committed to communicating openly with our clients and providing them with the highest level of service and cleanliness. We treat every home like our own. We were recently awarded the "Neighborhood Favorite" award for the second year in a row.

"Quin and his team were a pleasure to have work on my property! I cannot recommend them enough. The work is above my expectations and compared to other companies much easier on my wallet. Do yourself a favor and hire this group! "

Lauren D on March 2025

At McIntosh Construction , we believe in honesty, integrity, and transparency. We are committed to communicating openly with our clients and providing them with the highest level of service and cleanliness. We treat every home like our own. We were recently awarded the "Neighborhood Favorite" award for the second year in a row.

"Quin and his team were a pleasure to have work on my property! I cannot recommend them enough. The work is above my expectations and compared to other companies much easier on my wallet. Do yourself a favor and hire this group! "

Lauren D on March 2025


Avatar for Richbuilt Basements & Remodeling
Richbuilt Basements & Remodeling
2.83(
6
)
Approved Pro
Richbuilt Basements & Remodeling
2.83(
6
)
Approved Pro
35 local quotes requested
37 years of experience

My name is Rich Kempa I started this company in 1989. Prior to this I was working as a design draftsmen in many fields including Architecture, electric, plumbing, heating ventilating and air conditioning. I built my first house in 1985 and lived there 15 years until my family outgrew it.Was doing a lot of remodeling in my spare time and was ready to take it on full time. I really do enjoy the work and love to see the finished product. We have finished over 150 basements since then and still counting. Please contact me for a long list of referrals.

"Great. Everything was done as promised."

Dave J on October 2023

My name is Rich Kempa I started this company in 1989. Prior to this I was working as a design draftsmen in many fields including Architecture, electric, plumbing, heating ventilating and air conditioning. I built my first house in 1985 and lived there 15 years until my family outgrew it.Was doing a lot of remodeling in my spare time and was ready to take it on full time. I really do enjoy the work and love to see the finished product. We have finished over 150 basements since then and still counting. Please contact me for a long list of referrals.

"Great. Everything was done as promised."

Dave J on October 2023


Avatar for Easter Fence, Deck & Renovations
Easter Fence, Deck & Renovations
6071 Lemay Ferry Rd.
4.57(
142
)
Approved Pro
Easter Fence, Deck & Renovations
6071 Lemay Ferry Rd.
4.57(
142
)
Approved Pro
Customers say: Quality work
1675 local quotes requested
68 years of experience

Easter is one of the best-known and trusted fence, deck and renovation companies in the Midwest. Committed to “doing what’s right,” they are your good neighbor. The Easter Family guarantee is – “Even if it is the first job Dad did in 1957, if we didn’t do it right or didn’t do what we said, we’ll fix it for free.

"Vinyl fence repair. One post needed reset and turned out to be more difficult than expected but job was finished on schedule and no issues after spring storms with heavy rain."

Steve R on May 2024

Easter is one of the best-known and trusted fence, deck and renovation companies in the Midwest. Committed to “doing what’s right,” they are your good neighbor. The Easter Family guarantee is – “Even if it is the first job Dad did in 1957, if we didn’t do it right or didn’t do what we said, we’ll fix it for free.

"Vinyl fence repair. One post needed reset and turned out to be more difficult than expected but job was finished on schedule and no issues after spring storms with heavy rain."

Steve R on May 2024


Avatar for Maris Home Improvements, Inc.
Maris Home Improvements, Inc.
208 Chesterfield Industrial Blvd
4.85(
54
)
Approved Pro
Maris Home Improvements, Inc.
208 Chesterfield Industrial Blvd
4.85(
54
)
Approved Pro
Customers say: Quality work
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
1443 local quotes requested

Family owned and operated, we perform. With over 20 years of experience we know what it takes to make you happy. We are local in Chesterfield and our top priority is a satisfied customer.

"I had a horrible experience with Maris Home Improvements. I don't recommend them. You are better off going with Window World!"

Monica C on May 2025

Family owned and operated, we perform. With over 20 years of experience we know what it takes to make you happy. We are local in Chesterfield and our top priority is a satisfied customer.

"I had a horrible experience with Maris Home Improvements. I don't recommend them. You are better off going with Window World!"

Monica C on May 2025


Avatar for Main Event Landscaping
Main Event Landscaping
Main Event Landscaping And Remodeling
4.89(
9
)
Approved Pro
Main Event Landscaping
Main Event Landscaping And Remodeling
4.89(
9
)
Approved Pro
Customers say: Terrific value
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
789 local quotes requested

Your satisfaction is very important to us. We pride ourselves on the quality work we provide, while delivering great customer service! Check out our services offered.

"They did a great job with my mulch install job. Very nice and efficient. I would hire them again."

Ian W on June 2025

Your satisfaction is very important to us. We pride ourselves on the quality work we provide, while delivering great customer service! Check out our services offered.

"They did a great job with my mulch install job. Very nice and efficient. I would hire them again."

Ian W on June 2025


Avatar for Bella Landscape & Construction, LLC
Bella Landscape & Construction, LLC
611 East Osage Street
5.00(
16
)
Approved Pro
Bella Landscape & Construction, LLC
611 East Osage Street
5.00(
16
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
648 local quotes requested

We strive for excellence and 100% satisfaction for all of our clients. We have many families that have grown with us over the years as proof of our dedication. Our accounts range from residential, commercial, churches and charities. Our Vision Statement: "It's the connection between your dreams and our dedication." Our Mission Statement: To create a beautiful safe natural environment

"First time using Bella and the crew of five were fast and efficient and did a fantastic job. I would highly recommend them."

David L on April 2025

We strive for excellence and 100% satisfaction for all of our clients. We have many families that have grown with us over the years as proof of our dedication. Our accounts range from residential, commercial, churches and charities. Our Vision Statement: "It's the connection between your dreams and our dedication." Our Mission Statement: To create a beautiful safe natural environment

"First time using Bella and the crew of five were fast and efficient and did a fantastic job. I would highly recommend them."

David L on April 2025


Avatar for Romine Contracting LLC
Romine Contracting LLC
1055 Cantebury Cir
4.93(
110
)
Approved Pro
Romine Contracting LLC
1055 Cantebury Cir
4.93(
110
)
Approved Pro
Customers say: Quality work
Recommended by 98% of Angi customers
Recommended by 98% of HomeAdvisor customers
466 local quotes requested

Romine Contracting, LLC has over 40 years combined experience in renovation and remodeling. We work closely with our clients to ensure they are involved from the beginning of the project to the end so as to guarantee their complete satisfaction. We have superior craftsmanship, integrity, pride and quality that can be seen in every project that we do. Customers are what makes our business grow so thank you for allowing us to help make your home or business something to truly be proud of.

"My kitchen remodel is beautiful. It took one week longer but was worth the wait. We had minor issues but they were all handled with the utmost care and ownership. Communication was great and I am so happy I hired this company. Vinny was the best, I highly recommend them."

Orli R on May 2025

Romine Contracting, LLC has over 40 years combined experience in renovation and remodeling. We work closely with our clients to ensure they are involved from the beginning of the project to the end so as to guarantee their complete satisfaction. We have superior craftsmanship, integrity, pride and quality that can be seen in every project that we do. Customers are what makes our business grow so thank you for allowing us to help make your home or business something to truly be proud of.

"My kitchen remodel is beautiful. It took one week longer but was worth the wait. We had minor issues but they were all handled with the utmost care and ownership. Communication was great and I am so happy I hired this company. Vinny was the best, I highly recommend them."

Orli R on May 2025


Avatar for Patriot Landscape
Patriot Landscape
Based In
5.00(
2
)
Approved Pro
Patriot Landscape
Based In
5.00(
2
)
Approved Pro
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
537 local quotes requested

We specialize in all phases of landscaping, hardscaping, above ground pools, semi-inground pools, 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!

"Top notch service- had new mulch put down throughout by entire yard in addition to having old plants removed and new ones planted. Very professional!"

Christine T on August 2023

We specialize in all phases of landscaping, hardscaping, above ground pools, semi-inground pools, 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!

"Top notch service- had new mulch put down throughout by entire yard in addition to having old plants removed and new ones planted. Very professional!"

Christine T on August 2023

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FAQs for addition to existing structure building service projects in O Fallon, MO

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 O Fallon, MO 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.
BRIGHT OPEN ATTIC SPACE
Jun 10, 2025
Jun 10, 2025
An in-law suite is a great solution for people who have family visiting often. Explore how much an in-law suite costs and prep to build yours.
white and gray kitchen with butchers block countertop
Apr 8, 2025
Apr 8, 2025
Looking to enhance the warmth and utility of your kitchen? Explore how much a butcher block countertop costs and start your budget here.
built-in outdoor kitchen with grill and sink
Apr 30, 2025
Apr 30, 2025
Budget for outdoor kitchen costs based on factors such as appliances, materials, permits, labor, amenities, kitchen size, customizations, and more.
BLUE TWO STORY HOME
Apr 30, 2025
Apr 30, 2025
Budget for the cost to add a second story based on factors such as size, foundation work, materials, labor, permits, post-construction cleaning, and more.
small bathroom that has been updated in a remodel
Apr 29, 2025
Apr 29, 2025
Budget for the cost to remodel a small bathroom based on factors such as required fixtures, bathroom size, labor, remodel type, site prep, and more.
guest house in the backyard
Apr 27, 2025
Apr 27, 2025
Need to build a guest house? Here’s how much it costs, what factors affect cost, and what to expect.
Share project details to get started.