Interior design straddles advice and delivery. A designer who only draws has one exposure, a designer who buys on the client's behalf has a second, and one who runs the trades on site has a third. Most practices do all three without separating them.
Specification is professional indemnity
Choosing a fabric that fails fire regulations, specifying a floor unsuitable for underfloor heating, getting a lighting scheme wrong, or producing drawings a contractor cannot build from are claims about the advice. Professional indemnity answers, and the limit should reflect the cost of putting a finished room right rather than the design fee, because the two are rarely in proportion. Claims made cover means continuity and run off matter here as they do for any consultant.
Procurement, and holding a client's money
Designers who buy furniture, fabric and fittings on a client's behalf are handling client money and taking on a supply role. Goods paid for and not delivered, a supplier's insolvency, or a piece damaged in transit all become questions about who bore the risk and when title passed. A clear agreement about whether the designer buys as agent or as principal decides the answer, and it decides which policy is even relevant.
On site, and the trades you introduced
A designer visiting a live site is a visitor in a hazardous place, and one directing trades is closer to a contract administrator. Public liability covers injury and damage caused by the designer. It does not cover the work of trades introduced to the client, which is their own liability, unless the designer contracted with them directly, in which case the designer is in the chain. Knowing which of those two arrangements applies on each project is the single most useful thing a practice can document.
The client's property, in your care
Samples, antiques, artworks and furniture in the designer's possession or in transit are somebody else's property in your custody, which public liability handles poorly. A goods in trust or all risks extension is what covers them. Designers who store client purchases between delivery and installation carry a larger exposure than they think, particularly where a single item is worth more than the whole project fee.
Questions people ask about interior designer insurance
Does an interior designer need professional indemnity?
Yes. A specification that fails, drawings that cannot be built from or a scheme that has to be redone are claims about the advice, which only indemnity answers.
Am I liable for the trades on site?
Only where you contracted with them directly. Where the client engaged them, their work is their own liability, which is why the contracting structure should be documented.
Is client furniture in my store covered?
Only with a goods in trust or all risks extension. Property in your care, custody and control is handled poorly by public liability.