> I expect the insurance would not cover it.

I see this blanket assertion in lots of comment threads, but never with a citation.

> (just like it doesn't cover fires caused by storing gas or propane in your garage)?

This is an assertion I have never seen before. It is extremely common to keep gas cans in the garage around here (IL, USA), where else would you keep them that is safer?

I have discussed it at length with the USAA insurance people, I expect there are policy documents on their web site. The exact discussion was, "If the source of the fire is tracked back to a leaking gas can or a propane tank we won't cover the loss, we recommend you store flammables in a shed away from your house."

My impression from them was they were very dubious about "off book" uses of things as well, which leads to my expectation that they would push back on covering a loss due to a "home made" battery wall. Could I sue them and get them to cover it? I don't know, perhaps. But, as with my propane tanks, I would keep this stuff out away from the house to limit my losses and avoid having to go there.

I googled "insurance fire caused by gasoline in garage" and found https://cpsc.gov/content/consumers-warned-against-storing-ga... as the third result. "CPSC also warns consumers that private storage of more than a limited amount of gasoline (usually five gallons or less) is illegal in many areas, and subsequent fire damage may not be covered by insurance policies."

although IANAL, storing a large quantity of lithium ion batteries seems likely to be considered negligence, which is generally not covered under insurance.

Here is a quote from my insurance policy (Erie Insurance):

> “We” do not pay for loss resulting directly or indirectly from...the discharge, dispersal, release or escape of any solid, liquid, gaseous or thermal irritant, pollutant or contaminant, including smoke, vapors, soot, fumes, acids, alkalis, chemicals and waste

I checked another insurer (State Farm) and they had similar language:

> We do not insure, however, for loss...caused by...Discharge, dispersal, seepage, migration, release or escape of pollutants...Pollutants means any solid, liquid, gaseous or thermal irritant or contaminant, including smoke, vapor, soot, fumes, acids, alkalis, chemicals and waste

Keep reading the Erie policy. Look for phrases like:

"...into or upon the land, the atmosphere or any course of or body of water, whether above or below ground."

and

"but this exclusion does not apply if such discharge, dispersal, release or escape is sudden and accidental."

I'm pretty confident you will find them, or something similar.

I looked, but I don't see anything like that. The exclusions for smoke and water damage do not apply to "sudden and accidental" losses but the pollution one does. And it does not limit it to contamination of the environment.

My Erie policy was emailed to me, but here is a State Farm policy (not the one I quoted above) that has a similar exclusion:

http://www.opic.texas.gov/images/TDI_Approved_Policy_Forms/S...

That said, from googling I gather that there has been a lot of litigation over what counts as a "pollutant," including specifically whether gasoline counts. So I don't think that the presence of this clause means that an insurance company will always try to exclude any losses involving gasoline. I just think maybe they would have an argument if they wanted to.

Look at page 21 of that document.

"This (pollution) exclusion does not apply to bodily injury or property damage:

... (3) caused by common household chemicals used to maintain the residence premises."

Additionally, and perhaps even more importantly, this exclusion is in the "Personal Liability" section of the policy. The coverage/exclusions for the "Dwelling" are on pages 8-12.

Ah, interesting, I didn't read that to include gasoline but I see how one could argue that it does. The Erie policy has no such language.

In any case, thanks for the responses. My gut reaction is to agree with you that a lot of these "homeowners insurance will deny your claim if you do X!" warnings are based on third-hand knowledge or misinformation. I don't have any special knowledge though. (Do you?)

Edit: oops, you're right of course that I was reading the wrong part of the State Farm document! I swear I am not reading the Erie one so carelessly though.

> I see this blanket assertion in lots of comment threads, but never with a citation.

Imagine a company whose only product is one that if anyone uses, they lose profit. It doesn't take a huge leap of imagination to believe insurance companies will blame literally anything to deny coverage on a house fire.

And imagine if you had a house fire and had your coverage denied. Would you be at all shy of posting those details on a public forum? I'm not saying that denials like this can't/haven't happened, just that I've never seen a first-hand account of such an occurrence (it's always somebody's cousin's co-worker's son).

> (just like it doesn't cover fires caused by storing gas or propane in your garage)

What about the gas in your car or lawnmower?

Where do you store your camping stove?

The insurance texts posted downthread don't actually seem that "damning" to me. They talk about chemicals etc in a blanket sense. If insurance companies were worried about the gas can for your lawn mower, they would come right out and say it.

It's not uncommon for cities and homes associations to prohibit sheds anyway. A gas can in the garage seems a lot less volatile than one sitting in the sun that looks like it's ready to burst.

> The insurance texts posted downthread don't actually seem that "damning" to me. They talk about chemicals etc in a blanket sense. If insurance companies were worried about the gas can for your lawn mower, they would come right out and say it.

Why do you think that? I believe the purpose of the exclusions isn't to warn you about what bad things not to do, but rather to allow them to get out of covering certain losses. So broader is better (for them).

The idea the homeowners insurance doesn't cover the homeowner being negligent or stupid seems to betray a misunderstanding of what homeowners insurance is generally used for, namely protecting the mortgage lender from a catastrophic loss of the property's value.

In this case, since I don't have a mortgage, it is really covering my losses. Should my house burn down I don't want to have to go out and pay to rebuild it. I'm willing to take the actions the insurance company requires in order to keep their actuaries happy.

For anyone who isn't aware, California has seen a number of large scale disasters over the last couple of years which have destroyed many homes. From the fires in Santa Rosa to mudslides in Santa Barbara. And I have a number of friends and acquaintances who have been having painful discussions with their insurance companies about what they will and won't cover. I am fortunate that I have not suffered a loss. Seeing that pain though led me to call up and have a long, recorded, and detailed discussion with my insurance company about how they decide what to cover and on what basis they feel entitled to deny a claim. As with people who have actually lost their homes I was surprised at the number of things that they would use as a reason for not paying a claim.

One consistent theme was "unusual hazards that the insurance company was not made aware of." This ranges from people who have turned their garage into a place to do car repairs (adding lifts etc) to people who brew beer under the sink in the kitchen.

On the basis of that conversation, and the assumption that my insurance company was 'typical', I don't expect the battery fire to be covered. :-)

Did you take notes on these conversations? I'm very curious :)

In this particular case I recorded it :-) (with the permission of all involved) so that in the event there was some discrepancy about who said what I could refer to the recording.

Any other specific examples you care to share of things that you were surprised to find would not be covered?

Not really, there was an interesting digression into the question of using/installing "industrial equipment" (I've always wanted a CNC machine center for my garage.) We have an "industrial" washer and dryer pair (but that was ok). No sense turning this battery example into an insurance thread.

> No sense turning this battery example into an insurance thread.

aww

There's a difference between being negligent (leaving the stove on) and performing unlicensed DIY electrical modifications that were not approved by code inspectors and involve storing huge amounts of energy.

Exactly. Insurance will generally cover anything that it doesn't specifically exclude in the insurance documents. If you are walking with a can of paint and drop it and destroy your carpet most homeowners policies will pay to replace the carpet. If you leave the water on in the tub (by accident) and flood your house the policy will most likely pay for it. However it won't cover floods from the outside. But it will cover water that comes in from the roof or through the windows (subject to any exclusion for hurricane potentially).

Likewise if you decide to put together an array of lithium batteries in your bedroom most homeowners policies should cover that. After all those batteries already are in products in the house (as opposed to gasoline which would only exist in a lawn mower in small quantities in the garage).

What is most likely to kill you in most fires is the smoke and that is definitely true about Lithium battery fires.

This what makes them so deadly on a plane: you cannot get away.

Assuming that your smoke detector reacts properly to that kind of smoke, you should put one near your battery array.

In many cases it will only burn down the dedicated battery shed.