Creating Award Winning Dream Homes

Mars Building Ltd - New house builders, domestic extensions, alterations and all types of building works

Based in Knebworth, Herts, Mars Building Ltd is an established, family run business, with over 25 years building experience.
We work mainly in the Hertfordshire (Herts) area with most of our contracts being in Welwyn, Stevenage, St Albans, Hatfield, Harpenden, Knebworth, Hertford, Welwyn Garden City, Potters Bar, Brookmans Park.

The majority of our building work has come through recommendation, which has enabled us to build a very good customer base, generating new and repeat business.

Mars Building (house building, domestic extensions and building works), Groundwork and Demolition Services throughout Hertfordshire (Herts), Knebworth, Welwyn, Stevenage, St Albans, Hertford, Hatfield, Welwyn Garden City, Harpenden, Potters Bar, Brookmans Park and surrounding areas provided by MARS Builders

Read Our Blog

  • Passivhaus
    Passivhaus We have just completed a new build Passivhaus, a challenging but extremely rewarding build. The definition of a Passivhaus is- a rigorous, voluntary standard for energy […]
  • New year for Mars Building Ltd
    It’s 2017 and Mars Building Ltd is pushing ahead, last year we had the wonderful experience of working on BBC 1’s DIY SOS and made some […]
  • DIY SOS The Big Build Welwyn Garden City
    A few weeks ago I got a call from the BBC’s DIY SOS team asking if we would be interested in helping out on a potential […]

Why Choose Mars Building Ltd?

Our Customer Satisfaction Promise:

Mars Building Ltd has been built on reputation; we know that we are only as good as our last job so with our building projects you get:

No hidden extras

When we price a building job, we provide a detailed quotation, so you will know exactly what is and what is not included. This means there is no question of any hidden extras!

Quality assured

All our builders and tradesmen are fully qualified and experienced. They have worked together for many years.

Everyone works to the same high standards, with the same aim - to achieve the best possible results with complete customer satisfaction.

Service you can rely on

We know that once your house and life have been disrupted by the start of building work, the last thing you want is for nothing to happen for days or even weeks on end. With Mars Builders this does not happen.

We only take on building projects which we are sure we can cope with, which ensures that we can achieve full continuity of work on all our contracts.


Please call us:
Tel : 01438 812949
Mobile : 07956 503162

Feel free to contact us regarding any of our services. We have a friendly team that are always happy to help in whatever way we can.