About SmartSpec Extensions
Building excellence since 2006
Part of the Crownhill Building Services Family
SmartSpec Extensions is the dedicated extension arm of Crownhill Building Services, combining nearly 20 years of construction expertise with the latest building technologies.
Founded in 2006, we've built our reputation on reliability, quality craftsmanship, and complete customer satisfaction. Our team has remained consistent throughout our history, bringing unmatched experience to every project.
We specialise in home extensions throughout Milton Keynes and surrounding areas, using advanced methods like screw pile foundations and composite materials to deliver faster, smarter builds without compromising on quality.
Why Choose Us
What sets us apart from other extension builders
On Time, Every Time
We turn up when we say we will and finish when we promise. Your time matters to us.
Zero Insurance Claims
In nearly 20 years, we've never had an insurance claim. Quality work means peace of mind.
Respect Your Home
We work tidily, clean up daily, and treat your property as if it were our own.
Proven Track Record
Over 800 completed projects and counting. We're happy to show you our previous work.
Ready to Start Your Project?
Get in touch for a free, no-obligation quote and see why hundreds of homeowners trust us with their extensions.