Modular Principal Contractor

OSM (Offsite Manufactured) Construction was one of the first product agnostic specialist modular principal contractors in the UK, operating in the South East of England from our office in West Sussex. Modular or Modern methods of construction (MMC) build solutions are ideal for fast tracked projects where onsite construction time is limited. These solutions are quick to install, flexible, and sustainable making them ideal for bespoke, temporary and affordable, residential or commercial schemes.

Projects identified for modern methods of construction over traditional construction typically have different requirements, such as short timescales and limited space. But no matter how large or small the challenge, the OSM Construction team has the expertise and skills to deliver the right solution. With specialist experience in modular construction OSM Construction can advise our clients on a number of possible solutions and services, delivering the one most suitable for the project brief and budget.


MMC specified projects can deliver time savings of between 10 to 50% of construction time on site.


MMC solutions can be produced to exact specifications and quality assured before they leave the factory doors ensuring quality of the highest standards such as active or passive house standards.


Modular construction is factory led and therefore much more efficient than conventional build methods, creating savings in materials, time and money throughout the whole process.

Why off-site modular

Off-site manufactured construction projects are higher quality, quicker, cleaner and quieter to build than traditional buildings. In addition to these benefits, off-site construction produces up to 90% less waste than traditional on-site methods, making it more environmentally sustainable.

Factory-based manufacturing and construction minimises the time on site, meaning less noise and disruption, as well as a cleaner, safer and less congested site. If you would like to find out more about the benefits off-site modular construction could bring to your project, please get in touch with one of the team.

Why choose OSM Construction?

  • Detailed, transparent and no obligation quotations
  • Professional, fully insured building contractor
  • Comprehensive guarantees on all building services and products
  • Exceptional reputation for┬ácustomer satisfaction
  • Highly experienced in off-site construction
  • Knowledgeable about the variety of modular options, presenting the best solution for each project
  • Friendly and courteous tradespeople providing excellent service

We can act either as a full design and build principal contractor, working with a number of different prefabricated offsite suppliers tailor picked to suit your project, or as the principal contractor as part of a larger, client led team. If you have a project in mind that you would like to discuss with us, please get in touch.