Here is a report from western Australia about a way to limit the construction of McMansions: approve smaller residential lots.
The McMansion is likely to become architectural history as small blocks take over as the more popular housing lot size in WA.
Research by the Urban Development Institute of Australia said 60 per cent of blocks approved in Perth and Mandurah this financial year were less than 500sqm.
In 2004-05, only 30 per cent of all approvals were for blocks of this size. The increase has become pronounced in recent months, with 2130 small blocks approved in the December quarter compared with 1462 in the three months to September.
UDIA chief executive Debra Goostrey said the change had been driven by land prices, and a greater acceptance of small properties amid changing demographics.
It sounds then like development is becoming denser and houses are becoming smaller in this part of Australia. And there is also information on the lot size and house size trends over time:
A typical 1940s home had 125sqm of floor space on a block that was 1150sqm, or a quarter acre.
In the 1950s, block sizes fell to about 750sqm and homes were typically 150sqm in size.
The extravagant 80s brought in the era of the McMansion, with the floor spaces of homes blowing out to 300sqm and this became more extreme in the 1990s, with homes typically covering 350sqm of floor space on a 650sqm block.
It is interesting that this story emphasizes the size of the lot. Of course, this would have some effect on the size of the home that can be built on the lot but not necessarily. One issue that frequently comes up in American communities with teardowns is that the new owners want to build a relatively large home compared to the relatively smaller size of the lot. This can lead to situations where the new home, often dubbed a McMansion dwarfs older single-family homes. In response, many communities have developed guidelines about the new home including height restrictions and how much of a lot the new home can cover.
The article suggests that lots are becoming smaller because of prices and “changing demographics.” Is any of it due to larger concerns about sprawl? Compared to the typical quarter-acre lot of the 1940s, many of the lots today are less than half of that size. There is also mention in this article of an interest in more infill development. It sounds like there could also be some zoning issues going on as governments pursue denser forms of residential development.