Home Extensions in Mill Hill | Design & Build Specialists

Give your Mill Hill home more room to grow. Bespoke extensions designed around your family and built to last.

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Client reviews

Anjana Chakraborty

Very happy with Connor and Callum’s work on our home! Professional, courteous, considerate and extremely helpful was how we found Connor and his team to be. I liked the clarity of the payment schedule and the invoices. I was able to discuss with Connor any questions or concerns that I had and was grateful for the helpful suggestions. What I also really liked was that delivering what I, the client wanted, was clearly uppermost in Connor and his team’s minds. We will be contacting Connor again for any other work we want done.

Mary Peristiani

Connor and his team are great they told me exactly what the problem was where it was and what had to be done. Fantastic job will be using you again and would highly recommend these guys to do every job big or small ..

Astra Jamieson

Finished converted loft in Arnos Grove

We recently had our loft converted by The Construction Specialist , and we couldn’t be happier with the results. From the very first consultation with Connor to the final handover, the team was professional, transparent, and incredibly skilled.

They took the time to understand exactly what we wanted, provided helpful suggestions along the way, and delivered everything on schedule and within budget. The quality of workmanship is outstanding — the new space blends seamlessly with the rest of the house and feels like it was always meant to be there.

Connor kept us updated throughout, and the whole team was respectful, tidy, and hard-working. Any minor issues that came up were resolved quickly without fuss.

We now have a beautiful, big new bedroom with an ensuite bathroom that has completely transformed our home. I would highly recommend The Construction Specialist to anyone considering a loft conversion.

Buster Reynolds

I don’t often do reviews but I genuinely couldn’t be happier with how this bathroom renovation has turned out. The customer service was great, Connor and his team were really nice, in constant communication and they just did an amazing job! Couldn’t recommend them more, 10/10.

Redhead Rhys

We recently had the pleasure of working with Connor at Construction Specialist on our loft extension, and we couldn’t be happier with the results.

From the very beginning, Connor was approachable, professional, and genuinely invested in bringing our vision to life. He took the time to understand exactly what we wanted and offered thoughtful suggestions along the way that really enhanced the final outcome.

The transformation of our loft has been incredible, what was once an unused space is now a beautiful, spacious bedroom complete with a well-designed en-suite and practical attic storage. Every detail has been finished to a high standard, and the quality of workmanship is clear throughout.

Connor kept us informed at every stage of the project, was always reliable, and made what could have been a stressful process feel smooth and manageable. His attention to detail and pride in his work really stand out.

We’re absolutely delighted with our new space and would highly recommend Connor and the team to anyone considering a similar project. A genuinely great experience from start to finish.
We will definitely be contracting Connor and his team for our future builds and homw developments.

Keem Curtis

Connor and his team done amazing work at our house. They converted our garage into a play room with a 10/10 finish. We also had a major structural issue. They ripped up all flooring repaired all joists, insulated it and made sure it was fully supported with noggins. We are so happy with there work. Thanks guys

about us

Home Extensions in Mill Hill: The Complete Guide

Across Mill Hill, families are increasingly extending their homes instead of searching elsewhere for more space. We’ve built and refined our approach over 150 completed extensions, several of them within easy reach of Mill Hill. A quarter of a century spent building across North London and Hertfordshire has given us a genuine feel for how Mill Hill properties are put together. Choosing to extend lets you skip stamp duty, estate agent fees and the stress of house-hunting, while gaining a kitchen-diner, extra bedroom, home office, or living space designed around how you actually live. We know Mill Hill well: the types of properties, the planning considerations, and the approach that tends to work best with the local council. We’ve built efficient working relationships with planning and building control teams, which helps keep Mill Hill projects moving without unnecessary delay. Every extension we deliver in Mill Hill reflects the same commitment to quality craftsmanship, clear communication, and transparent service.

Our Services

Your Local One-Stop Construction Team in Mill Hill

Loft Conversions

We specialize in turning empty attics into bright bedrooms. We handle all structural changes to ensure the new space feels like a natural part of your home.

Renovations & Refurbishments

Update your current rooms and improve the layout. We modernize interiors to make them more comfortable and better suited to your family lifestyle.

Home Extensions

Need more room on the ground floor? We design and build extensions that improve your living space. We manage the full build from foundations to the roof.

Roofing Services

A reliable roof is essential for any home. We provide new installations and repairs using materials that are tested to last against the British weather.

Kitchens & Bathrooms

We install functional kitchens and luxury bathrooms. Whether it is a new en-suite or a kitchen refit, we handle all the plumbing and installation work.

New Builds & Self Builds

Building a new home is straightforward with our team. We keep the project organized and on schedule, ensuring a high quality finish from the ground up.

Years of Experience

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Why choose us

Trusted Construction Partner

Mill Hill Local Experts

We are a trusted company based in Barnet. Being local ensures we provide fast responses and understand Mill Hill building rules perfectly.

25+ Years of Experience

With over two decades in the industry, we know how to handle complex builds. Our experience helps us work efficiently and avoid common mistakes.

Fully Managed Projects

We take care of everything for you. Planning, structural work, and final construction are all handled by our team so you have one point of contact.

Workmanship That Lasts

We take pride in our building standards. Every project is completed using quality materials, ensuring a durable result that adds value to your home.

Expert Construction in Mill Hill

The goal for any Mill Hill project isn’t just more room, it’s a home that flows better and still looks like it belongs on the street. It comes from a combination of considered design, tight project management, and a refusal to cut corners on quality. We take the time upfront to understand your priorities, then produce plans detailed enough that there’s no ambiguity about how the finished extension will look or work. We make sure logistics, timelines and any property-specific issues are on the table early, so your Mill Hill project starts with clear expectations, not guesswork. The same team structure underpins every job: thoughtful architectural design, solid engineering, and tradespeople who care about the finish as much as the fabric. We use quality materials, follow strict safety standards, and take care to protect your property throughout the build. Every job is backed by full professional insurance and a written workmanship guarantee. It’s not unusual for a Mill Hill client to call us back for a second project — usually the best sign that the first one went well. A well-built extension should make daily life better and strengthen your home’s value in the local Mill Hill market — that’s the outcome we aim for.

Our Process

How We Get the Job Done Right

Initial Consultation

We visit your home in St Albans to look at your space. We discuss what you want to achieve and provide an honest assessment of what is possible.

Stage 1

Design and Planning

Our team creates a clear plan for the build. We coordinate the drawings and make sure the design follows all local building and safety regulations.

Stage 2

Structural Construction

Our builders carry out the work with care. We focus on the structural integrity of the build while keeping disruption to your daily routine very low.

Stage 3

Regular Project Updates

We keep you informed with regular updates. You will always know the current status of the project and what the next stages of the construction will be.

Stage 4

Final Quality Check

We perform a final inspection to ensure everything is perfect. Our work is only complete when the new space meets our high standards and your satisfaction.

Stage 5

Our portfolio

Showcasing Our Latest Building Projects in Mill Hill

View examples of completed loft conversions and residential projects delivered across Mill Hill, Watford, Hertfordshire, and North London.

FAQ

Frequently Asked Questions

How long does a home extension take?

Most extensions take 3-6 months depending on size and complexity. We provide detailed timelines during planning so you know exactly what to expect.

Do you handle planning permission?

Yes, we manage the entire planning process. Many extensions fall within permitted development, but we advise on all requirements specific to your property.

What does an extension cost?

Costs vary based on size and specification. We provide detailed, transparent quotes after our free consultation with no hidden costs or surprises.

Are you insured and experienced?

Absolutely. We carry full professional insurance and have 25+ years delivering high-quality residential extensions across North London and Hertfordshire.

Do you work in Mill Hill?

Yes, we’re based in Barnet and serve Mill Hill and surrounding areas. We have extensive experience with local properties and planning. Contact us to discuss your project.