House size doubles?

Sounds like one of those interesting questions that an academic economist could usefully explore.

What, exactly, has been the expansion (or not) of the average living space of the average (I guess we’d need to say median, right?) household in the US?

Tap into the house, apartment, mobile home information, come up with a number. Correct by the change in household size and we would see something about:

“This seems a bit surprising given that (on standard measures) real wages for large groups of workers have not increased since the 1970s.”

We would find out something about whether real wages, as measured by consumption (of housing, to be sure), had in fact gone up or down, would we not?

Hmm, anyone know an academic economist interested in this question?

What Matt said, obviously. Families live in houses, incomes of families went up, problem solved.

How do apartments impact average house size? Is it that people with lower incomes don’t have to purchase small housesa, thereby increasinf the average size?

Taking manufactured homes into account would substantially lower the size of the average new home. It would also fit the income data, showing rising inequality, a lot better.

Perhaps. But, the manufactured house my sister lives is about the same size as the family home we lived in as kids (about 1200 square feet). Hers has two bathrooms compared to our one and central A/C (which we didn’t have for the first 10 years we lived there). There were six of us in that house, while my sister lives alone. And my father had a higher status job than my sister does.

In general, I think you’ll find that the size of manufactured homes in the U.S. has ballooned, too. And keep in mind that the average number of persons in a household has dropped significantly, so the amount of living space per person has increased much faster than the average house size. Even for people living in unexpanded older homes, the decline in family sizes has translated into much more living space, on average (what used to be a family home is now considered appropriate for a single or a couple).

I really don’t think you’re going to be able to explain away this affluence.

With respect to manufactured homes, there’s this:

Manufactured Housing: Growing in Size and Popularity

According to the Manufactured Housing Institute’s analysis of U.S. Commerce Department and Census Bureau data, the average square footage of a new manufactured home increased from 1,335 in 1996 to 1,595 in 2002. The average size of a conventional home increased from 2,090 square feet to 2,301 square feet over the same period.

Many customers are now purchasing multisection homes — known in the popular parlance as “doublewides” — or even two-story homes that are erected on site and sell for $85,000 and up, according to Savage.

http://www.prb.org/Articles/2004/ManufacturedHomesaBigFactorinRuralHomeownershipinUS.aspx

It appears that manufactured homes have expanded size slightly faster on a percentage basis than conventional homes.

(household table.)

Here’s another table, on the numebr of housing starts. One thing that’s clear is that the proportion of single-family homes has risen sharply — from about 60 percent in 1968 (where the table starts) to 80 percent today. So unless new apartments are shrinking awfully fast, the average size of houses+apartments is growing even faster than the average size of houses.

In this case, once you take account of manufactured homes, along with the other points already mentioned, this counterclaim looks a lot weaker.

Mobile homes growing in size faster than conventional homes would tend to make the claim stronger. Mobile homes making up an increasing percentage would tend to weaken the claim. Taking the two together, it’s probably a wash or at most a very small effect (after all, we’re talking about 8 percent of the market).

And you’re neglecting the steady reduction in persons per household. Even if house sizes had remained constant (which, of course, they have not), the housing space per person would have increased 30% just based on the decline in household size (from 3.4 to 2.6) between 1950 and 2000.

Lastly, this is one of those areas where consumption inequality (in terms of utility, not dollars) has decreased, regardless of what has happened with income inequality. The average family that earns $500K a year certainly doesn’t live in a house that’s 10 times larger than the family making $50K. The increase in house size is obviously not linear with income.

And in the last decades, the houses of people of the middle class have been equipped with all of the features that were formerly luxury items (washers, dryers, microwaves, central A/C, video systems, cable-TV, game consoles, computers, etc) whereas no significant new types have been invented that remain the exclusive province of the rich (unless, perhaps, you count ‘whirlpool tubs’).

If you’re looking for a place to confirm rising inequality, I suspect you’ll be disappointed looking at housing.

Keep in mind that doubling over a period of fifty years is really a quite modest annual qrowth – less than 1.4%/year, if I can trust my botec. So it would not be surprising to see people purchasing larger houses as long as their real income was keeping pace.

Western housing patterns haven’t kept up with western living patterns. Explain why the average size of the western home keeps increasing but young people keep paying increasingly large rents for rooms in share houses, while their parents upsize to increasingly large homes with no-one in them. Meanwhile in Japan single young people can live in dirt cheap studios. Western housing markets are, in general, a complete mess, as are western planning rules. In combination with the so-called housing “boom”, the result is an increasingly stupid and complicated housing market, where everyone pays too much for something they don’t need.

What about the productivity increases of construction in that period? Even if construction workers they haven’t – perhaps especially if they haven’t – received increased wages as a result, more productivity means more home for the money. Standardized home plans, more pre-fab, mechanization, better tools (pneumatic nail guns anyone?), cheaper, better materials (plastic pipe) etc. all have made bigger homes cheaper.

I feel as if it’s conventional wisdom that one reason why ‘mcmansions’ have become so common in the States is that material costs have been decreasing, and this in turn pushes down revenues and profits for anything other than really large houses.

That said, I looked where I thought I remembered seeing that claim, and didn’t find it. So conventional wisdom-eh….

A little anecdotal info from 30+ years in construction. In the early seventies, IIRC, new houses were around 12-1500 sq. ft. in places I worked, NY and northern CA, with many on the low end of those sizes. Over the next 5-10 years, during periods not in recession, it became difficult for small builders and for homeowners to finance such “small” houses. The sizes grew to 2000 plus, with lenders demanding at least two full baths or two and a half baths. As the pattern was set, every few years the current size-on-average became a defacto minimum with the size tied by lenders to their sense of what would constitute safe loans. A kind of economic red-lining.

John (or Tim), I happen to have the American Housing Survey 2003 semi-massaged and SAS-ready. It has four housing types (single family detached, attached, multi-unit and manufactured). Not perfect because it compares units of all ages still around. However, for houses of 2-6 bedrooms, for example, the median home_sq_ft used to be much lower than the mean, but is inching up towards it for newer homes. And if you want a one- or two-bedroom detached house, you’re probably getting an old one.

Within the house-type and number-of-rooms (or bedrooms) square footage has risen by a more modest 25-40% or so (by the intraocular comparative test) and the fraction of new houses with more bedrooms is up compared to the fraction of older homes still around.

I haven’t looked at income, rents, rural/urban or pmsa variations, but they’re in the dataset, alogn with mortgage payments, rents and state of repair. It’s off the Census website, or I could send you my 850MB SAS file.

John Q, what about the effect of land cost? Since new home construction is generally farther out in the suburbs, the house itself can be affordable at a larger size because the land (which is a substantial portion of the overall cost in many places) is that much cheaper.

a fixed stock like housing takes a long time to adjust

Though in the US, my guess is that it adjusts faster than most places. Americans do like knocking down buildings.

(My parents are still not comfortable with the whole idea of wooden houses. The Three Little Pigs shapes the British homebuilding industry fare more than its American counterpart.)

The flatapartment I’m in is, I’d guess, more or less the same square footage (967 sq ft) as the 3-BR semi I grew up in. But it’s what would be considered temporary housing for most people in the area. Indeed, with apartments, you have to consider that outside urban areas, they fall into two categories: where poor people live, or where more aflfuent people live for a short period while looking for a house.

In general, I’d agree with sg: housing is one of those markets where there’s always a gap between what’s optimal and what’s available, but the disparity between the two in the west (and certainly the US) is pretty big. I’m interested in grackle’s comment #30, though, which ties square footage to the willingness of lenders to finance purchases.

And abb1, dude, doesn’t it occur to you to spend 30 seconds checking something before making a confident—and in this case completely wrong—declaration of fact?

I didn’t feel it was necessary because I still remember the lecture – video linked by Chris Bertram a few days ago on this site. The very first graph in that lecture showed the average family income going up, seemed like quite a bit higher than 10%. Perhaps those were different kinds of stats? I dunno, she was talking about the average family.

Incidentally, something was said there about the average house size as well. I remember she said that it increased slightly – one more room or one more bathroom, but not both. That’s from 1970 to 2005.

Statistics…

“You will observe, Watson, that every dwelling in this street has a double-garage which the owners use to keep the wind and rain off Mr Daimler’s invention.”

From Sherlock Holmes & the Strange Death Of Off-Street Parking 1896

New McMansions are often remarkably flimsy compared with their early twentieth-century counterparts.

I’m not sure that it was a steady trend, though. The first house my wife and I bought was built in 1978. It felt significantly more flimsy (with shoddy wiring too) than either the 1950s house I grew up in or the 2006 house I now inhabit. The 2006 house has various features (e.g. hurricane clips now required by code) which probably make it better able to withstand high winds than the early 20th century homes nearby.

As quo vadis suggests above , many of the older homes in my area have nice work inside, but the foundations are crumbling and floor joists are rotting due to the vented crawlspace. Newer homes built on slabs or sealed crawlspaces seem better designed for the climate in the southeast.

“My parents are still not comfortable with the whole idea of wooden houses. The Three Little Pigs shapes the British homebuilding industry fare more than its American counterpart.”

Yeah, but the story leaves out digging the Third Little Pig’s corpse out of the rubble after a big earthquake.

At least on the West Coast, wood’s the way to go for structural reasons, unless you’re going to make your house out of reinforced concrete.

“I’m picking up the sound of snark here, Tim,”…true, written pre-caffeine, apologies.

With no snark: the expansion or not of housing area per capita, if we knew it accurately, and could adjust for the different qualities (mobiles, prefabs, McMansions, apartments) might tell us something about whether incomes have in fact increased or not?

Fair enough, f. blair.

Here is the data on median and average square feet of new homes.

median:
1973 = 1525′
2006 = 2248′
increase = 68%

average:
1973 = 1660′
2006 = 2469′
increase = 67%

In neither case did the size double, but there has clearly been an increase in size for new constructions.

However, as noted by Warren above, “Today, nearly six out of ten families own a home that is more than 25 years old, and nearly a quarter own a home that is more than 50 years old.”

Which means that 60% live in homes with a median size of 1550′, which is was the median in 1981.

Which means that 60% live in homes with a median size of 1550’, which is was the median in 1981.

No it doesn’t, necessarily. Additions. My house, built in 1956, was first expanded in the early 1980s. then I bought it and built another addition. In the end it had become at least twice the original size.

Thanks for the data, Andrew. I actually think the data you posted is more relevant to the original question at the heart of John’s post than the 1950 data is, since 1973 was also when the postwar boom ended. This is precisely what John was trying — and failing — to explain with his mobile-home theory: even as wages have stayed flat in the last 35 years, the size of new homes has risen sharply (more sharply, I suspect, than it did between 1950 and 1973).

However, pointing to ‘additions’ is rather a rather spurious argument unless you believe for some reason that putting additions on homes is a recent innovation.

No — the point is that the houses that existed in 1981 whose median size was then 1550′ — those exact houses — are larger on average now than they were 27 years ago because of additions during that time.

As the NY Times Levittown article noted — a decade ago there were still almost 200 unmodified Levittown houses whereas now there are almost none. So the average size of even the average 50-year-old Levittown house increased during the last decade.

Slocum,

My mistake. Thanks for pointing out the flaw in my logic.

The AHS has the median square ft/person.
In 1993 (the earliest date I could easily find data on), median sq ft/ person was 689′.
In 2005 it was 752′.

If anyone knows where to find data from 1973 or so that would be super.

Ignore that last figure – the data doesn’t go back far enough to calculate it properly. But presumably, median family income during WWII wasn’t so high as to invalidate the basic argument: the average non-immigrant in 2006 had parents with a 1973 level of income, the 1973 generation didn’t.

Martin James…
Strange comment (not sure how to take it actually), it clearly isn’t fully serious. And well who cares abut you, to be blunt. You don’t seem to worry about anybody else.

But back to the theme. Surely the telling point is that housing is a stock and income is a flow. You pointed this out and then have forgotten about it. That plus the trade off poeple have made with increased commutes. Whether people really are better off like that, is another point (they spend less and less time in their big houses because of the commutes and working to pay off the mortgage) and a large part of the time they are there, they are asleep. But then housing is a positional good. The utility comes not from owning the house, but from bragging about it.

John Q. (and Tim Worstall, from the other side) think the puzzle is that a major increase in housing consumption is incompatible with flat household income. John Q. suggests the former must therefore be false, Worstall the latter.

But the evidence is pretty clear that both facts are true, partly because housing costs have declined, but mostly because people are choosing to spend more on housing.

Why people choose to devote to more of their incomes to housing is the puzzle. Presumably, it’s some mix of:

1. Regulations have made it more difficult too build smaller homes.

2. The specialized mortgage-lending system makes it easier to finance housing purchases than alternative forms of consumption. (Yes, this was probably at least as true 30 years ago, but as more and more consumption is debt-driven, ease of financing becomes more important.)

3. Houses becoming more attractive as an investment as well as consumption good. Especially true in the bubble period, obviosuly, but probably a longer-term trend.

Untangling these explanations — and whatever others I’m not thinking of — is an interesting question. But John Q.’s approach, of trying to find reasons why housing consumption has not increased as much as it seems to have, is pretty clearly barking up the wrong tree.

And 5:

Changes in school costs and the legal framework in which schools operate made lving in a uniformly high-income area much more valuable.

Abb1,

Good try at cutting a deal, but you’re never going to make it as a real estate broker unless you tell the buyer the house is BIGGER than reported and tell the mortgage company that the buyer’s income is BIGGER than reported.

These arguments became a lot less meaningful to me when I started looking carefully at the time use statistics. Across all adults in the USA, the average work hours per day is 3.75 hours, the average leisure is 5.09 and of that 5.09, 2.58 is spent watching TV. Big house, flat income, who cares? What people really seem to want is a good TV show.

Average income for married households is up more than 10%, but the percent of households that are married persons has dropped significantly.

The national association data you link to gives the average size of a new home in 2005 as 2,434 sq. ft..

But the Census housing survey has the median size of the existing housing stock at 1,768 sq ft.==
this is 72% of the data you linked to.

I did not check to see how far back the Census housing survey goes back, but you might want to check that data.

Isn’t tracking square footage of houses a really serious example of looking under the lamppost?

At 21, I posted census data showing a significant increase between 1984 and 2006 in the share of household spending going to housing. So the phenomenon does not seem to be just an artifact of looking at square footage.

dang ya’ll
In 1950 less than 8% of households had a college grad as head of household and less than 33% of households had 2 wage earners. By 2005 more than 20% of households had a college grad as head and almost 66% of all households have 2 wage earners. Lots of these households have 2 college grads. Housing is a function of income with housing costs increasing at rate greater than income. Given the puzzling evidence that a much greater percentage of households own a home and that it is a much nicer home than previous generations, maybe your understanding of income growth/inflation needs adjusting.