Design & Construct and Design & Build Professional Indemnity Insurance
Contractors' Professional Indemnity Insurance for building, design and build, and mechanical and electrical contractors who take on design responsibility.
Whether you design in-house, prepare specifications, or accept contractual responsibility for design carried out by others, standard contractors' all risks and public liability policies will not respond to a claim for defective design. We arrange specialist cover for smaller contractors, typically with turnover below £5 million, subject to insurer acceptance.
Risk Exposure
Why Contractors Need Professional Indemnity Insurance
A Design & Build contract, a Contractor's Design Portion, or an NEC Option X15 places a duty of care on the contractor that goes well beyond workmanship. Once you are responsible for design, a claim can be made against you for rectification costs, consequential losses and delay damages where that design is alleged to be defective.
Design responsibility does not always look like design work. A contractor can be exposed by preparing specifications, selecting materials and building systems, offering value engineering alternatives, coordinating subcontracted design, or simply signing a contract that makes them responsible for a design produced by somebody else.
Where design is subcontracted, the main contractor usually remains liable to the employer for that design. The consultant's own Professional Indemnity policy may carry a lower limit, may have lapsed, or may not respond at all — leaving the contractor to meet the claim.
These claims generally fall outside contractors' all risks and public liability cover, which respond to injury and physical damage rather than the financial loss caused by defective design, specification or professional advice.
Contractors' Professional Indemnity Insurance is written on a claims-made basis. The policy in force when a claim is notified has to respond, even where the work was carried out years earlier, which makes the retroactive date one of the most important features of your cover.
Scope of Cover
Design Responsibility We Can Consider
Cover is arranged around the design responsibility you actually accept, so underwriters will look at how the design work is carried out and who is responsible for it. Smaller contractors carrying out design and build work are considered on their own merits rather than against a minimum size.
Illustrative Claims Scenarios
Typical Claims Scenarios
The following scenarios are illustrative examples only. They are not actual PLB claims and do not describe any individual policyholder. Any insurance response would depend on the circumstances of the claim and the terms, conditions, exclusions and limits of the policy.
Specification Error in a Refurbishment
A contractor specifies a render and external wall system that is unsuitable for the exposure of the building. Water penetrates within two winters and the finish has to be removed and reinstated, along with damaged internal finishes. The employer claims the cost of remediation, professional fees and loss of use of the building against the contractor.
Defective Design Produced by a Subcontractor
A design and build contractor subcontracted the structural design of a small commercial unit to a consultant. Errors in the design require strengthening works and delay the handover. The consultant's own insurance has lapsed, so the employer pursues the contractor as the party responsible for the design under the building contract.
Mechanical and Electrical Design Error
An M&E contractor designed and installed ventilation and air conditioning for a restaurant. After completion the kitchen extraction and temperature control do not perform as specified, and the restaurant has to close while the systems are reworked. The operator claims the cost of the remedial works and the lost trading during closure.
Accepting Design Responsibility Under a Design & Build Contract
A contractor tendered for a design and build project on the basis of the employer's existing drawings and specification. Defects in the drainage and ground levels were inherited rather than created by the contractor, but the contract made the contractor responsible for the design. The employer claims the cost of the remedial drainage works against the contractor.
Proposal Information
What Underwriters Usually Ask
When we approach the market on your behalf, underwriters will typically require the following information. We guide you through this process.
Why Choose PLB
Specialist Design & Construct Contractors PI Brokers
Sector Expertise
We understand the specific professional risks facing design & construct contractors and arrange cover that responds to your actual exposures.
Market Access
Access to specialist Professional Indemnity underwriters and markets with experience in this sector.
Personal Service
Deal directly with experienced PI specialists who know your sector — not a call centre or an algorithm.
Frequently Asked Questions
Design & Construct Contractors — Common Questions
Get Started
Request a Quotation
Complete our specialist proposal form and a Professional Indemnity broker will review the information provided and contact you within one working day.