Offer your thoughts or opinion on the input financial query or topic using your financial background.

For a major expensive home renovation (e.g. addition, finished basement, or new kitchen) should one pay cash or finance with a loan? Would such a loan be “good” debt?
The number one reason to borrow is quite simple; when you have no other choice. The primary reason to do this is when renovations or additions must be made in a timeframe that precludes you being able to save enough money to pay cash. Harmanjd's example of a kid on the way with no space to put him is a very good hypothetical. Disaster recovery is another; insurance doesn't cover everything and can sometimes be slow to pay out, and even if the payoff will rebuild the house exactly the way it was, these situations are deceptively good opportunities to improve on what you had. Since you already have to call in the contractors to demo and rebuild, the cost to do that is sunk, and the incremental cost of improvements or even additional square footage is relatively minor. Other acceptable reasons to borrow are: When cost of capital is very cheap. A typical amortized HELOC is pretty expensive when paid on-schedule, but if you can pay it off very early (i.e. when you sell the home next month) or you get a good deal on the interest rate (a subsidized disaster recovery loan, perhaps; you have to be careful with these as they're not intended to turn a burnt-down hovel into a McMansion) the cost of borrowing can be acceptable even if you had cash savings for the project. You have other uses for the cash that can offset cost of borrowing. This generally requires the first point to be true as well, as it's a general rule that borrowing $10,000 costs you more than you would gain by investing $10,000, but there are situations in which the reverse can be true (if you have $10k in oil or major tech stocks right now, it would probably be a bad move to liquidate them for home improvements if you can get a HELOC at less than 6%). You can realize a net gain in home value from the reno. These situations are rare in cases of an already livable home; "flippers", which make their living on renovating homes for a profit, generally choose homes with obvious but easy-to-fix problems that depress home value because they look worse than they are. If you bought your home without any such problems, you probably paid something close to market value at the time, and so you're probably behind the curve. However, if you (or your family in the case of an estate transfer) have owned the home for a long time, long enough for things to fall WAY out of date, then you can catch up a lot of market value with one renovation, where if the home had had two or three renovations along the way a reno now wouldn't gain you as much value.