Home Extensions
Create the space your home has been missing. We design and build single-storey, double-storey and wrap-around extensions — from foundations and structural steelwork through to a fully finished, decorated room that flows seamlessly into the existing house. One team, one standard, one point of contact.
Expert home extensions across Hertfordshire
Create the space your home has been missing. We design and build single-storey, double-storey and wrap-around extensions — from foundations and structural steelwork through to a fully finished, decorated room that flows seamlessly into the existing house. One team, one standard, one point of contact. We're proud to be trusted house extension builders, rated 4.9/5 by 115+ homeowners across Hertfordshire and North London.
- Single & double-storey extensions
- Foundations & structural steel
- Building control & regs managed
- Seamless tie-in to your existing home
Curious about pricing first? See home refurbishment cost guide.
Why homeowners trust us with their home extensions
Premium, high quality finish in every detail
Punctual, reliable and finished on schedule
Clean and tidy — your home protected every day
Fully insured with a workmanship guarantee
Rated 4.9/5
“Not a single thing I can fault”
I wanted to make sure I was giving an honest review so I waited to really put the new bathroom to the test... There is not a single thing I can fault! The Nicolla Contractors team were excellent at communication, timekeeping and professional in all manners. They gave some unreal advice on the best products and materials to use within the bathroom for a long lasting high end finish. … Nothing was ever too much trouble and I can not recommend them enough. … I HIGHLY HIGHLY recommend!
Home Extensions across our areas
Common questions
Many single-storey rear extensions fall under permitted development, but it depends on the size, your property and whether you're in a conservation area. We assess this early, handle the planning or lawful-development application where it's needed, and never start ground works until approvals and building control are in place.