Naming someone as additional insured does not make your policy theirs.
A general or an owner asks to be added to your liability policy before you start. It can give them cover for a claim that comes out of your work, and it is not written to reach beyond that. The gap between what the contract asks for and what the paper actually delivers is where the argument happens.
Build the contractor file Read the short answer firstCover follows what you did.
Fault that is only theirs stays theirs.
A certificate is not the policy.
What does additional insured status actually give someone?
Cover for their part in a claim that arises out of your work, and only that. The Canadian Construction Documents Committee says court decisions have settled this: the negligent acts of an additional insured are covered, “provided such negligent acts are related to the Named Insured’s contract”.
The limit is the one you already bought. Adding a party does not add money, it shares your money. What it does not reach is a loss that came only from their own negligence. If the owner is sued for something they did on their own, with no link to your work, your policy is generally not the one that answers.
The same committee says most insurers in Canada do not add additional insureds by endorsement, and issue a certificate instead because it costs less. The policy itself usually says it can only be changed by endorsement. The certificate then says on its own face that it does not amend the policy. CCDC’s advice is to know what the contract requires, compare it with what the insurance representative provides, and question any difference. Read CCDC Bulletin 4 (2025) on additional insureds (opens in a new tab).
Four things to settle before you sign.
What the clause actually asks for
Some ask for additional insured status. Some ask for a waiver of subrogation with it. Some ask to be named for years after the work is finished, and on CCDC 2 jobs that clock runs from Ready-for-Takeover. Read the words, not the summary someone sent you.
Endorsement or certificate
If all you have is a certificate, ask your broker whether a blanket additional insured wording sits behind it. That wording is what makes the certificate mean something. Blanket wordings usually only work where a written contract asked for the status before the loss.
How long it runs
CCDC 2 asks for owner and consultant cover for six years after Ready-for-Takeover, a milestone that contract defines. That is not the day you finish, and cover that ends when you finish does not meet it.
Whether your limit still fits
You share your limit with everyone you add. A limit that suited one company can look thin once three parties sit on it.
Three jobs, three arguments. All three are illustrations, not client files.
The certificate that changes nothing
A trade sends the general a certificate showing the owner as additional insured. The policy itself is never endorsed. When a claim comes, the argument is about whether the owner was ever added.
The claim that is not about the trade
Someone is hurt by work the owner did themselves, before the trade arrived. The owner turns to the trade’s policy. Where nothing arose out of the trade’s work, that is not the policy the wording points to.
The limit that runs out early
A firm adds party after party across several jobs. One serious claim can use that limit for all of them at once, and the firm ends up sharing the money it bought for itself.
The questions trades ask about this.
Does adding someone cost me more?
That depends on the insurer and the wording. Some charge for it and some do not. The real cost is that they now share your limit.
Can I just send a certificate?
You can. Ask whether your policy carries a blanket additional insured wording, because that is what stands behind the certificate.
If the owner is sued, does my policy pay?
Only where the claim arises out of your work. A claim about something the owner did on their own is not yours to answer.
Can an additional insured sue a named insured?
They can sue. Whether your policy answers it is a separate question. Most additional insured endorsements only give that status for liability arising out of your work, so when an owner sues you over your own work they are usually suing as a third party rather than as a fellow insured, and the claim is read the way any third party claim is read.
Does being on the same policy stop one insured suing another?
No. Most Canadian wordings carry a Separation of Insureds condition, so cover is read as if each insured were the only one. That changes how exclusions written about the insured are read, but it creates no cover, and exclusions written about any insured still apply to everyone. The limit stays shared. Some wordings and some wrap-up policies go the other way and carry a cross suits exclusion.
The contract wants six years after Ready-for-Takeover. Is that normal?
Yes on CCDC 2 jobs. It is a completed operations question, so check that your own policy reaches that far.
They want to be named on my tools policy too.
Ask why. Additional insured status belongs on liability cover. On property cover, being named usually means something quite different.
Two that sit next to this one: what a clearance letter and a certificate each prove, and what a project wrap-up does and does not do for your own company.
Not the question you came with? Send it through the short contact form and we will answer the one you actually have.
Know what you are signing before the job starts.
Send us the insurance clause and your current certificate. We will tell you what matches and what does not.
Checked for technical accuracy by Amrit Sidhu of S&S Insurance Services Ltd. Last checked 28 September 2026.