Will anyone want to buy a 4,000 square-foot house 30 years from now?

I'm house shopping and have some reservations about buying the biggest suburban house I can afford. Here are the facts that concern me:

1) Energy costs are high.
2) Whether the U.S. comes up with more alternative energies or just keeps using the traditional sources, costs can go nowhere but up. (Coal, oil etc. are still available but harder and more expensive to get out of the ground; and windmills, solar, etc. are going to require big up-front investments that are going to make these forms of energy expensive too.) So energy costs can only go up.
3) Big houses will have huge utility bills 30 years from now, so demand for big houses will probably plummet as fewer people will be able to afford their long-term expense.

Will anyone want my big house if I try to sell it 30 years from now?

I should explain that the reason that coal and oil can only get more expensive is that these resources have already been mined for decades. The easy-to-access stuff has been mined; what's left is the more difficult (and hence more expensive) stuff.

Congratulations, u looked at a point most people are in denial about . energy costs.
are u buying the 4000 sq ft because u have 12 people in your family? cause u'll be entertaining high priced clients at home?
are u going to be staying home cause u don't have money left over after expenses to do any thing else. cause ever one else is doing it.
do you have enough cash reserves (not credit cards) to pay for expenses during a 6month layoff, off-shoring, company closure, medical condition or Murphy moving in?
suggest u visit daveramsey.com to get a better view of house buying b4 u do.
a house is a place to lay ur head , to warm ur bones, to eat with family and friends
unfortunately most buyers are conned into what everyone else believes they should buy.
THAT is why i'm over worked.

Big families will always need big houses. But...families are not getting larger as the years go by. Also it's not a good idea to buy the most expensive house in your neighborhood. You want to be in the middle or near the bottom of the price range. If you're at the top and the market takes a downturn, your house with depreciate faster than the less expensive ones.

There will always be people who can afford to buy it no matter what prices go to. I would say yes, if you told people 30 yrs ago they would be paying 3-4 dollars a gallon of gas they would have said no one will ever pay it. They would be wrong. Same will go 30 years from now.

There will always be a desire for larger homes some as group homes or bed and breakfast. Extended families my like living together to save money. But they probably won't want one jammed up against the next house with nothing special about it and low quality construction. Some of the new stuff is no better built that mobile homes so won't be worth anything in 30 years.

Cost of energy has gone up the past 30 years and people kept buying bigger and bigger houses. I remember the gas crisis in the 1970s when the Chicago Tribune headlines read that gasoline hit 60 cents a gallon. Who would have thought everyone would be driving SUVs thirty years later.

I wouldn't worry about it -- 4000 square feet is not all that huge compared to what they're building by me. My previous house built in 1999 was 5500 sqft.

real estate, like all big investments, are a gamble. Depends on location. the economy, the future. If anyone knew what today would be like in 1977, they'd be RICH N HEALTHY. Enjoy it for 30 years n worry about it then. In the mean time, HOPE you can make the payments.

Most people never stay in their homes for 30 years...I bet you are basing that number off of the fact that your loan is 30 years...most people refinance their 30 year loans every 5 - 7 years, and move about every ten years or so. So the question could be, can you sell a 4000 sq foot home in ten years...which will be yes. Can you sell it in 30 years...of course because just like you said, energy prices are going up, but they have been going up for the past 30 years and will continue to do so. You pay them now and you will pay them then...just like gas.