We operate in the automotive, commercial, industrial, education, healthcare, and development sectors.

Leading Principal Contractor on The South Coast

Square One Construction delivers integrity, expertise, and a collaborative approach to every project - ensuring our clients’ vision becomes a built reality.

As one of the South Coast’s leading principal contractors, we specialise in delivering high-quality construction projects on time and within budget – without compromise.

Our commitment to excellence goes beyond the build. We prioritise the highest standards of health and safety, environmental responsibility, and client satisfaction at every stage of the process.

From pre-construction planning and mobilisation through to construction, defect-free handover and ongoing aftercare, we offer a fully integrated project delivery service that ensures clarity, quality, and confidence from start to finish.

Recently Completed Projects

Education & Healthcare

Brighton, Hove & Sussex Sixth Form College (BHASVIC) – East Sussex

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Commercial & Industrial

Oil Spill Response – Southampton

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Automotive

Mercedes Benz – Maidstone

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"An extremely professional outfit, they were a pleasure to work with and we were able to maintain our operations during the 8 month build. Looking forward to working with them again on our next development."

"A quick line to say how pleased I am with the quality and finish at Croydon. Special thanks to Russell who I know started early, finished late, worked several weekends and got the job over the line"

We have worked with the Square One team on numerous projects. Our most recent being for the most prestigious brands and on a high profile site. As a team we have produced a beautiful building whilst keeping the build cost below budget and delivering on time. A pleasurable experience, unusual in the construction world!”

Square One took positive ownership of the scheme on site, providing advice and buildability input when needed and maintained very good relationships with the end users which was key on a project requiring multiple phasing to keep the surgery operational throughout. The finished product was to a very high standard and slightly ahead of time. I would happily work with the Square One team again and have no hesitation in recommending them to others.

“Our state of the art Porsche Centre in Tewkesbury was constructed by Square One. The quality of the building is superb and the post handover support that has been given to me since opening the centre has been fantastic."

"Square One Construction has recently completed a refurbishment of Cooper BMW MINI Thames Ditton. Their workmanship and organisational methods have been a focal point to the success of the works. We found their attitude and commitment to liaise and coordinate with ourselves without fault. We look forward to working with them again."

“It has been a real pleasure working with Square One. The on site team work extremely well together and make construction look easy! Looking forward to the next project."

“Mini Chelmsford was a new build that had to be constructed adjoining an existing dealership and a private residence. Square One understood and dealt professionally with these constraints, working closely with all parties to avoid any issues. This approach makes a real difference and we look forward to working with Square One again in the future.”

Accredited CHAS Contractors

Members of Considerate Contractors

Safe PQQ Verified

Safe Contractor Approved

Retail Suppliers Qualification System

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