Do you mean unexpected or irregular?
Aah, that's a great question, I sort of alluded to it in my post above.
We have the odd unexpected irregular expense, like the garage door repair, but in being a home owner, I plan for there being some sort of $5200/year house/life expense. Just because you may not be able to name the exact cause of an irregular expense, doesn't mean you can't plan for it, using some sort of statistical calculation of the likelihood of needing something. Most of the 'emergency' things we've experienced (garage door needing repair to close, so my husband's tools wouldn't get stolen that night, or the time we had the pipes freeze and needed an emergency plumber to fix it) have been in the under $500 category. The cost of replacing an appliance (we had to replace the everything but the fridge within the first 1.5 years we owned the house, they were all 20 years old) also falls in line with that $500 mark.
In the case of other irregular, but expected expenses have included the furnace last year ($4200) and floors this year ($11,000), we plan and save in advance. Less money goes into the long term investment accounts in that time, and we try to time them for when we know we'll have extra money coming in, like the summer when my husband taught summer school.