There is a clause that they don't cover negligence "the loss did not occur through any wilful act or neglect, or the procurement, means or connivance of the Insured" I'm pretty sure modifying an electrical appliance to draw 20% more current than rated for (or in Canada 50% more than rated for) could easily be considered negligent
Negligence is covered. That's one of the main purposes of insurance. The clause you quoted deals with intentional acts. The "neglect" does not mean negligence. It means if you have knowledge of an intentional act and neglect to do anything about it (i.e. your spouse is going to burn down your house and you don't alert authorities) then you do not have coverage. Or if you procure or connive in the intentional act (i.e. you have someone else burn your house down - procure, or you secretly allow - connive). The
ejusdem generis rule applies to that clause and the word "neglect". There's a ton of case-law on it.
In fact, the clause you quoted comes directly from the
Insurance Act. For example, that exact wording is contained in section 29, Statutory Condition 6(1)(iii) of BC's
Insurance Act here (Alberta is similar but the section will be different):
(iii) stating that the loss did not occur through any wilful act or neglect or the procurement, means or connivance of the insured,
Table of Contents - Insurance Act
It is also contained on the Insurance Bureau of Canada Proof of Loss form (about 3/4 down the page).
"The said loss or damage did not occur through any willful act, neglect, procurement, means or connivance of the Insured or this declarant."
Fire:
http://assets.ibc.ca/Documents/Legal/Claims_Forms/GST/17CLAIMFRM.7.GST_2013.pdf
Other than Fire:
http://assets.ibc.ca/Documents/Legal/Claims_Forms/GST/19CLAIMFRM.8.GST_2013.pdf
If we accept that negligence is not covered, if you forget to close the door on your fireplace and it causes a fire - there's no coverage because you're negligent. That's absurd and defeats the entire purpose of insurance. Now, if you adapt your UMC
with the intent of burning your house down, and you want to make it look like an accident, then there is no coverage. That's very different than messing with something and accidentally causing a fire. That's very common and insurance pays those claims daily.
Having said the foregoing, I agree it's best not to mess with your UMC and insurance companies often deny claims without proper cause. But I don't want people to be left with the impression that there is no coverage in the absence of an anticoncurrent causation clause and even if there is one, you may live in a State where the Courts will not enforce it. As I said before, if you didn't intentionally burn your house down, and your claim is denied, seek legal advice. And if you have an insurance policy with an anticoncurrent causation clause then change insurers!