No, you are not being unreasonable. Presumably the water leaks were caused by fortuitous acts, not negligence or lack of maintenance, so there is no reason why you should not be able to make a claim on the policy which you help pay for!
The policy excess is probably in the region of �100, so with a claim ten times over this, it's not like you are making a claim for the sake of it. If the Co Sec or other shareholders refuse to allow you to attempt to claim, they are in breach of their lease obligations.