Contractors all risks is the cover for the thing being built. Public liability answers for harm to other people; contractors all risks answers for damage to the works themselves, to the materials waiting to go into them and often to the plant and temporary works around them. It is the section building firms most often do not have, and the one a fire or a flood on a part finished job turns into an immediate problem.
What sits inside the cover
The permanent and temporary works under construction are the core, usually on a contract value or annual turnover basis. Materials on site and sometimes in transit or in storage follow. Owned plant, hired in plant and employees' tools are commonly separate sections on the same policy, each with its own limit. Cover typically runs from the start on site to practical completion, with a defects liability period afterwards on many wordings, and the dates matter because the risk transfers at handover.
Why public liability will not do the job
Public liability responds to your legal liability to third parties. The building you are constructing is not a third party's property in that sense while the works are yours, and a claim for its own damage is not a liability claim at all. Insurers say so plainly in the wording, and the discovery usually happens after a storm takes a roof off a half built extension. The two sections are bought together for that reason.
Who is supposed to buy it under the contract
Standard building contracts allocate the works insurance explicitly, sometimes to the contractor and sometimes to the employer, and they name who is to be a joint insured. A domestic client extending a house is often expected to arrange it through their own buildings insurer, while a contractor on a new build is usually expected to carry it. Reading the insurance clause before signing is the whole job, because both parties assuming the other has it is the common failure.
What it does not answer for
Defective workmanship itself is normally excluded, though the resulting damage may be covered depending on the wording; that distinction is where most disputes live. Wear, gradual deterioration and faulty design are usually outside it. Theft from an unattended open site is often subject to conditions about security. None of that makes the cover weak, and all of it makes reading the exclusions worthwhile before the first delivery arrives.
Questions people ask about contractors all risk insurance
What is contractors all risks insurance?
It is cover for the works under construction, the materials for them and usually the plant and tools around them, against damage from causes such as fire, storm, flood, impact and theft. It is a property cover, not a liability one.
Is contractors all risks the same as public liability?
No. Public liability answers for injury and damage to third parties. Contractors all risks answers for damage to the works themselves. Most building firms need both, and a policy carrying only the first leaves the site itself uninsured.
Who pays for works insurance, the contractor or the client?
The building contract says, and both allocations are common: the contractor on a new build, the client through their own buildings policy on an extension or refurbishment. The important thing is that the clause is read rather than assumed.
Does it cover defective work?
Usually not the defective work itself. Some wordings cover damage that the defect causes to other parts of the works, and the exact wording decides. It is the most argued exclusion in this cover and is worth checking before a claim rather than during one.