Koolau
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Except for the RE crash years, a reasonably well located home plus lot would have had to suffer very bad luck to lose money.
It isn't very hard to figure out how your city is going to do, and it isn't very hard to pick the better districts of your city.
Agree completely. Our area never lost more than 20% in value even during the crash. Much of this stability was due to the "enlightened" (okay, maybe lucky) lending practices locally. "No doc" and other high-risk loans were rarely offered, so the cascade effects seen in other areas never materialized when the market got a little soft. Also, by being a very desirable area where "they aren't making any more land", prices have a natural "stability" built in. This has played out over many cycles in the past.
We were able to play the system to an extent and trade "up", locally. Our old area lost about 10% during the crash while our current area lost about 20%. Now, prices have rebounded to near pre-crash levels, so we "made" money (if we were to sell).
Having said all that, I still don't think of the home as an investment. Neither do I look at it as just an expense. It's sort of a "neutral" item that has characteristics of both. I don't look at it as part of the AA, but I certainly look at it as an asset which adds stability to the FIRE plan.
To the OP's question about a "rule of thumb", respectfully, I don't see that as being very useful - assuming that investable assets and other sources of income allow one to live in one's chosen abode without fear of running out of money. So, if half one's assets are in a house and the other half generate more than enough money to keep one IN that house, who cares about the percentages of total assets? Just my opinion, so YMMV.