4K Construction

design – build – renovate

Professional Cornish construction company ~ new builds, extensions, loft conversions, alterations and general carpentry/building work.

Cornwall Builders – 4K Construction – make building residential or commercial projects a success. 

Simply stunning residential building, commercial construction and architecture delivered on-time, on-budget and with zero defects.

These aren’t just bold claims – they’re what our clients have told us – have a look through our testimonials. 4K Construction will capture your design and build, refurbishment or extension vision, nurture your ideas and build an environment which is beautiful to the eye and a pleasure to experience time and time again.

It’s why 80% of our clients come from referrals alone. Our case studies are testimony to this.

Whether you need construction, architecture or design & build in residential or commercial environments, explore our site to find out more about what 4K Construction can do for your project.

Our services

Good design doesn’t date.


From bespoke custom carpentry projects making items individually crafted to a customer specification…


We have been the first choice for many companies and individuals providing a trustworthy service.


Many people require more space for their growing family, but might not want to move to a new house.


If you have decided to make improvements to your home, we are here to turn your ideas into a reality.

Residential Architecture

Basement Conversions

House Extensions

House Refurbishment

Loft Conversions

New Builds

Project Management

Commercial Architecture

Bar and Club Refurbishment

Commercial New Builds

Office Refurbishment

Shop Fitting

Project Management


  • I would highly recommend 4K construction they are friendly, hard working and are very reliable. They are outstanding craftsman with great attention to detail. I would definitely call upon their fantastic services again in the future.

    Catherine Owers
  • I spent some time trying to find a good builder when I needed to update the tired looking house that I was about to move into. I was therefore so pleased to discover 4K Construction who proved perfect for my needs. They have done a wonderful job of transforming my rather boring house into a much admired home. Not only did they have some good ideas for what could be done, but they were also very responsive to my ideas and requests as the work progressed. The standard of workmanship is second to none in my opinion, with great attention to detail, and I appreciated their constant concern to stay within my budget when looking at alternative ideas or of adding on extra jobs. They were clean, considerate and very efficient. All in all I am absolutely delighted and would not hesitate to recommend them to anyone.

  • Cannot recommend the 4K Construction team highly enough. The quality of workmanship is the very best. This was our first sizeable project to which their guidance proved invaluable. In fact we would have found ourselves out of our depth without them. They also produce creative ideas for the space which has transformed our build and made life much more practical. Everyone who sees the transformation speaks very highly. Thanks guys - you've done us proud

    Liz and Paul

Click to call AJ: 07926 766 201