What insurances does a principal contractor need to hold?

Insurance is a compliance item at tender and a live obligation for the whole project, including the defects period.

On government and institutional work it is checked before site access, not after.

The policies

**Public and products liability,** covering injury and property damage to third parties. Public sector contracts commonly specify a minimum sum insured, and on work around students, patients or the public the required limit reflects that exposure.

**Contract works,** covering the works themselves during construction, including materials on site and in some cases in transit. On a refurbishment inside an occupied building the interaction between this policy and the client's own building insurance needs to be understood rather than assumed.

**Workers compensation,** statutory, for every worker, and checked for every subcontractor rather than the head contractor alone.

**Professional indemnity,** where the contractor provides or procures design. Any [design and construct](/answers/does-monument-environments-do-design-and-construct) arrangement brings this into scope.

**Motor vehicle and plant,** for site vehicles and mobile plant.

Certificates of currency

Held, current, and produced before access. Expiry dates tracked, because a policy that lapses mid-project is a breach and, on some contracts, grounds for suspension.

The same applies to every subcontractor. A head contractor is responsible for verifying subcontractor insurance and for keeping the evidence, which is part of how [subcontractors are engaged](/answers/how-subcontractors-are-engaged-and-managed).

Indemnity and who carries what

Most public sector contracts require the contractor to indemnify the client against loss arising from the works. What matters is the scope of that indemnity and whether it is capped.

Two provisions are worth reading closely before signing.

**Consequential loss,** meaning whether the contractor carries loss beyond direct damage. On an occupied site that can be a large figure, because interrupting an operating facility has costs well beyond repairing the damage.

**Caps and exclusions,** and whether the indemnity is proportionate to the fault or absolute.

Why it matters more on live sites

A project inside an operating school, station or facility has a higher chance of affecting people and property that are not part of the works.

Which means the exposure is real rather than theoretical, and it is one of the reasons institutional clients set higher limits on this work and verify prequalification under schemes such as [SCM 1461](/answers/scm-1461-prequalification-explained).

What a client should verify

Certificates of currency for each policy, current at the date of access. The sum insured against the contract requirement. That the named insured matches the contracting entity. That the workers compensation policy covers the actual workforce. And that subcontractor certificates have been collected rather than promised.