Welcome to
JMB Design & Build,

where quality comes first.

We design, build and create beautiful spaces within your home.

JMB Design & Build is a building firm based in Hertfordshire run by James Boulton. James and his team of qualified craftsmen have more than 25 years of experience in the industry. 

We offer professional and experienced help with your projects from concept to completion, helping to match your vision, needs and budget.

JMB Design & Build prides itself on quality, professional workmanship and referrals from happy clients is the main source of all new work.

Contact us today and see how we can help transform your home.


We are very pleased with our kitchen extension. JMB did an excellent job. James set himself high standards and he was only content when these are achieved. This has culminated in a very successful project. Everyone loves our kitchen! We would not hesitate in recommending JMB.



COVID-19 has produced a new health and safety challenge but we have reacted swiftly to the advice and requirements of all regulatory authorities to protect our site and office based staff. Whilst the core aspects of compliance and risk controls apply to Covid as to any other health and safety risk, we have taken additional communication and measures such as social distancing and enhanced cleaning and PPE to protect our team and our clients. In addition, we have put additional support in place for the wellbeing of our team.


JMB Design & Build is a full service building construction company dedicated to building and improving residential and commercial structures according to client needs and desires.


We specialise in transforming your home into what you always wanted. Be it a loft conversion, extension or a new build from scratch. You can be rest assured that at JMB, quality, precision and excellence comes first.

Based in Hertfordshire but also covering London and Essex, the team at JMB is ready to give your space whatever updates it requires.

Just give us a call or enquire online today and we’ll get back to you as soon as we can with a quote.

Contact us today to see how we can help create your dream space.