People here talk about the risk of the markets being depressed at around the time when you have to sell. How much of a risk is that? A 10-15% short term drop in the equities market is a huge deal but overall won't affect you that much, since presumably you would only have to sell a part of your stash, not all of it. And if you have a more diversified portfolio (such as Permanent Portfolio or something similar) then chances are some of your assets will be going up with an equities market crash, and you could sell those off. Keep in mind that this is an "emergency" which may or may not happen, whereas losing money in a savings account due to inflation is something that is happening constantly.
I have about two months worth of expenses in my regular day-to-day use account. This just makes it simple if I have some large bill that comes up. Even then, when I've had large unexpected expenses come up ($10k, or 4 months of regular spending was the last big one) I just put it on my visa, then at the end of the month paid off most of it with savings and the rest with my line of credit. LOC is unsecured so not tied to house value, though that makes the rate a bit higher, and has room for about a year's worth of basic expenses. Credit cards have room for another year's worth of expenses so if I really had to I could bite the bullet and rack those up. TFSA has about a year's worth of expenses in it, which is an investment account so I could potentially take a bit of a loss if I had to sell, but see my first paragraph about the significance of that. So, without having a real "emergency fund" set aside I could lose both my jobs and if I couldn't find anything at all that makes money I could last about three years. After that I would have to dip into my RRSP, though I wouldn't have to pay tax on that if I didn't have any other income.