You dream it, we'll build it.
From lofts and extensions to full refurbishments, we deliver well-built spaces that add real value — managed properly from start to finish.
Ratings
5
Trusted reviews from Google
Schedule a
Free Consultation
You dream it, we'll build it.
From lofts and extensions to full refurbishments, we deliver well-built spaces that add real value — managed properly from start to finish.
Ratings
5
Trusted reviews from Google
Schedule a
Free Consultation
You dream it, we'll build it.
From lofts and extensions to full refurbishments, we deliver well-built spaces that add real value — managed properly from start to finish.
Ratings
5
Trusted reviews from Google
Schedule a
Free Consultation
We are a top rated 5 star builders and extension specailists
Excellent work, very pleased with all aspects of this extension project. Attention to detail and standard of workmanship were first class. Totally trustworthy, and reliable.
John Roe, Purley
We are a top rated 5 star builders and extension specailists
Excellent work, very pleased with all aspects of this extension project. Attention to detail and standard of workmanship were first class. Totally trustworthy, and reliable.
John Roe, Purley
We are a top rated 5 star builders and extension specailists
Excellent work, very pleased with all aspects of this extension project. Attention to detail and standard of workmanship were first class. Totally trustworthy, and reliable.
John Roe, Purley
We are a top rated 5 star builders and extension specailists
Excellent work, very pleased with all aspects of this extension project. Attention to detail and standard of workmanship were first class. Totally trustworthy, and reliable.
John Roe, Purley
Servicing in the West London and Surrey area
Servicing in the West London and Surrey area
Our Service - reimagine homes
Our Service - reimagine homes
Transform unused roof space into a bright, functional living area. From design to completion, we deliver high-quality loft conversions that add space, comfort and long-term value.
Transform unused roof space into a bright, functional living area. From design to completion, we deliver high-quality loft conversions that add space, comfort and long-term value.
Create more room to live, work and relax with a well-designed extension. We build seamless additions that enhance your home’s layout, flow and overall value.
Create more room to live, work and relax with a well-designed extension. We build seamless additions that enhance your home’s layout, flow and overall value.
Reimagine your entire home with a complete refurbishment. We upgrade, modernise and improve every detail, delivering a cohesive finish that transforms how your space looks and feels
Reimagine your entire home with a complete refurbishment. We upgrade, modernise and improve every detail, delivering a cohesive finish that transforms how your space looks and feels
Strong foundations are essential to every successful build. We deliver reliable groundworks and drainage solutions, ensuring your project starts right and performs properly for years to come.
Strong foundations are essential to every successful build. We deliver reliable groundworks and drainage solutions, ensuring your project starts right and performs properly for years to come.
We support your project from the earliest stages, coordinating planning and structural requirements to ensure everything is compliant, practical and ready for a smooth build process.
We support your project from the earliest stages, coordinating planning and structural requirements to ensure everything is compliant, practical and ready for a smooth build process.
From homes to commercial spaces, we deliver high-quality building work tailored to each environment. Every project is approached with the same care, precision and attention to detail.
From homes to commercial spaces, we deliver high-quality building work tailored to each environment. Every project is approached with the same care, precision and attention to detail.
25
25
25
25
We Don’t Just Build — We Transform Spaces
We Don’t Just Build — We Transform Spaces
STL Build is a local building company based in Sunbury-on-Thames, working across Surrey, South West London and the surrounding areas.
We go beyond simply constructing spaces. We help homeowners reimagine and unlock the full potential of their property — delivering high-quality, well-designed environments that add lasting value.
STL Build is a local building company based in Sunbury-on-Thames, working across Surrey, South West London and the surrounding areas.
We go beyond simply constructing spaces. We help homeowners reimagine and unlock the full potential of their property — delivering high-quality, well-designed environments that add lasting value.
Every project is fully managed from start to finish, with a focus on clear communication, careful planning and a clean, respectful approach on site. The result is a smooth, well-run build with minimal disruption and a finish that speaks for itself.
From loft conversions and extensions to full property improvements, our work is built on craftsmanship, consistency and trust.
Every project is fully managed from start to finish, with a focus on clear communication, careful planning and a clean, respectful approach on site. The result is a smooth, well-run build with minimal disruption and a finish that speaks for itself.
From loft conversions and extensions to full property improvements, our work is built on craftsmanship, consistency and trust.
Message from Simon
Message from Simon
Built on Experience. Delivered with Care.
Built on Experience. Delivered with Care.
I’ve spent over 25 years building and renovating homes across Surrey and South West London. Over that time, one thing has never changed — my attention to detail and the standards I expect on every job.
For me, it’s not just about the build itself. It’s about understanding how you live, what you need from your space, and making sure the end result genuinely works for you and your home.
I stay closely involved throughout every project to ensure everything runs as it should — from the first conversation through to the final finish.
I’ve spent over 25 years building and renovating homes across Surrey and South West London. Over that time, one thing has never changed — my attention to detail and the standards I expect on every job.
For me, it’s not just about the build itself. It’s about understanding how you live, what you need from your space, and making sure the end result genuinely works for you and your home.
I stay closely involved throughout every project to ensure everything runs as it should — from the first conversation through to the final finish.
"More than 25 years on, my standards haven’t changed — every detail still matters."
Simon Lack - Onwer
"More than 25 years on, my standards haven’t changed — every detail still matters."
Simon Lack - Owner
Kind reviews from our trusted customers
Don't take our word for it
“Absolutely fantastic! I would have no hesitation in using them again, nor recommending them. Great workmanship and very tidy."
Sarah Kitley
“Absolutely fantastic! I would have no hesitation in using them again, nor recommending them. Great workmanship and very tidy."
Sarah Kitley
"I would like to take this opportunity to State that the above Company have done work on our house on several occasions and I must state that the work and craftsmanship was second to none so I would recommend to anyone looking for any building work to be done get a Quote off this company 1st!"
Brian Pelham
"I would like to take this opportunity to State that the above Company have done work on our house on several occasions and I must state that the work and craftsmanship was second to none so I would recommend to anyone looking for any building work to be done get a Quote off this company 1st!"
Brian Pelham
“We used STL Simon Lack to build a double floor wrap round extension in 2014. The workmanship has been fantastic with no faults or problems in over 10 years of it being completed. Thank you Simon."
Ben Sarbutt
“We used STL Simon Lack to build a double floor wrap round extension in 2014. The workmanship has been fantastic with no faults or problems in over 10 years of it being completed. Thank you Simon."
Ben Sarbutt
“Very polite, helpful and competent. Work was done very quickly, to a high standard and left tidy and clean afterwards. Will use again."
Michal Majercik
“Very polite, helpful and competent. Work was done very quickly, to a high standard and left tidy and clean afterwards. Will use again."
Michal Majercik
“Simon completed a major extension for our house in Farnham during 2024/5. We were very happy with the quality of the work. He was hard working, tidy and punctual and always took time to explain to us what each stage was. Great job!"
Patrick Gurney
“Simon completed a major extension for our house in Farnham during 2024/5. We were very happy with the quality of the work. He was hard working, tidy and punctual and always took time to explain to us what each stage was. Great job!"
Patrick Gurney
“1st class service, would thoroughly recommend."
Nobby Norwood
“1st class service, would thoroughly recommend."
Nobby Norwood
“Fantastic building company!!! Simon is upfront and highly knowledgeable."
Lee Simpson
“Fantastic building company!!! Simon is upfront and highly knowledgeable."
Lee Simpson
We provide free, no-obligation quotes on every project, large or small. You’ll also get clear, friendly advice — wherever you are in the process.
Let’s talk
Schedule a Free Consultation
We provide free, no-obligation quotes on every project, large or small. You’ll also get clear, friendly advice — wherever you are in the process.
Let’s talk
Schedule a Free Consultation
We provide free, no-obligation quotes on every project, large or small. You’ll also get clear, friendly advice — wherever you are in the process.
Let’s talk
Schedule a Free Consultation
We provide free, no-obligation quotes on every project, large or small. You’ll also get clear, friendly advice — wherever you are in the process.
Let’s talk
Schedule a Free Consultation
Services
© 2026 All Right Reserved by STL LOFTS & EXTENSIONS LTD
Services
© 2026 All Right Reserved by STL LOFTS & EXTENSIONS LTD
Services
© 2026 All Right Reserved by STL LOFTS & EXTENSIONS LTD
Services
© 2026 All Right Reserved by STL LOFTS & EXTENSIONS LTD