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The United Kingdom has a housing crisis (see Financial Times, Shelter, The Independent, The Telegraph) and a housing quality crisis (killing 300015000 per year), due to poor insulation.
Cash-strapped local authorities aren't building. Despite this, new homes appear to be mostly built using traditional masonry.

I understand that prefabrication has higher quality and lower cost. What are advantages of masonry over prefabrication? Why would housebuilders in the UK choose the former?

masonry house
New British masonry house. Source: geograph (cc-by-sa 2.0)

bricklayer
Bricklayer. Source: Wikimedia Commons (cc-by-sa 3.0)

pre-fab house
Affordable pre-fab houses Spring Creek, Nehemiah, New York. Source: Wikimedia Commons (cc-by-sa 3.0)

See also flatpack skyscrapers, or those apartment blocks near Reykjavík, Iceland (I don't know if the latter are prefab, but they look to me like they could be).

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    $\begingroup$ Housebuilders like to make money. Brick is more desirable than prefab, so people will pay more for it. Housebuilders are not known for their altruism, unfortunately. Beware using newspapers as sources of research material - they are notoriously unreliable. $\endgroup$ – Wossname Aug 17 '18 at 10:42
  • $\begingroup$ @Wossname Brick is more desirable than prefab — is that so? Do you have a source for this? Am I in a minority of I think the house in the last photo, or other results for Google Image Search for prefab house looks far more appealing than the house in the first photo or than indeed any recent brick house in the UK? $\endgroup$ – gerrit Aug 17 '18 at 11:09
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    $\begingroup$ That photo isn't really representative of the broad term "Prefab". In the UK there is a very large number of prefab houses that were built during the war and provided to families by the government. Many of these are ugly (google: "unity type prefabricated house"), little more than simple slabs of concrete bolted together. You've picked a photo of a very modern, probably expensive prefab house. The "lower cost" is mainly found at the ugly/concrete end of the prefab scale. The concrete ones are cold and drafty and very small, they do not fetch high prices, thus builders don't favour them. $\endgroup$ – Wossname Aug 17 '18 at 12:21
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    $\begingroup$ From the Huf-Haus website huf-haus.com/uk/europa/london: The company produces a limited number of houses each year, around 150, which gives the concept an exclusive edge. Building 150 luxury homes per year isn't going to solve the UK's housing shortage - even if all 150 were built in the UK, which they are not! $\endgroup$ – alephzero Aug 17 '18 at 13:06
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    $\begingroup$ @gerrit, your comment about "painting bricks on" is baffling. I think this entire Question is based on a flawed understanding of the UK housing crisis and also a weak grasp on the principles of supply and demand and also how manufacturing on a large scale works. Perhaps you should close this Question and begin another one with a tighter focus on a specific question. The Economics stack exchange may actually be a better home for this kind of question because it has little to do with specific practical engineering principles. $\endgroup$ – Wossname Aug 17 '18 at 14:29
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In UK, building codes are unusual. There is something called Mobile Homes Act which specifies particular types of homes as being covered under different protections and building laws than masonry buildings. Basically put, politics had made prefab homes unattractive legally because you have to meet different ownership requirements related to land occupation than masonry homes.

This issue arose because government wanted to legislate against random land occupation by gypsies and the traveller communities which resulted in a stilted and broken recognition of what legally and politically constitutes a "fixed abode" without singling out a specific group or ethnicity of people.

Mobile home Mobile Homes are not covered under rent regulations and insurance companies are reluctant to insure them unless they are located in very specific conditions in their environment. If they are on a "trailer park" or "holiday park" the rates are quite different to ones with wheels removed. Masonry buildings are considered to be fixed assets whereas prefabs are categorised under moveable assets in the same way as caravans.

We can argue the point but the laws are so convoluted and Machiavellian that prefab homes are too expensive to build in quantity, politically or legally. They tend to be classed as park homes which can only be placed in certain areas under specific conditions if English Heritage agree to allow them to be built... such are planning laws in UK that a charity determines who build what and where it when they can build it. When it comes down to cost, it is not the material film which the home is constructed that accounts for the price but price is largely attributed to demand. These mobile homes cost about the same as a masonry home which negates the saving on materials.

Whilst a landlord will order a mobile home to be built for about £45k, they will charge between £80k & £140k to the prospective buyer. In addition to this, no landlords of mobile home parks will allow you to bring your own unit on-site because they don't make a pretty penny off you otherwise. One your home arrives, you start paying ground rent at around £70 a week in addition to buying the overpriced unit.

Better to buy a brick and mortar home that costs buyers about the same because you don't have to fork out an additional £36400 over 10 years in addition to the sale price of £120000. Both types of homes incur the same council taxes. Both cost around £160000. You cannot usually get a mortgage for prefab homes either which means only richer people can afford prefab.

The cost of a mobile home single unit is about £35k and sells for about ££90k.

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  • $\begingroup$ prefab <> mobile home $\endgroup$ – AndyT Aug 21 '18 at 8:47
  • $\begingroup$ The pictures (prefab?) house would be classified as "moveable asset"? $\endgroup$ – gerrit Aug 21 '18 at 9:24
  • $\begingroup$ Yes. It was prefabricated offsite and delivered I the back of a flatbed truck. $\endgroup$ – Rhodie Aug 21 '18 at 9:39
  • $\begingroup$ @Rhodie Oh, I see. When I think of prefab I think of flatpack-style: components fabricated offsite, assemled onsite. $\endgroup$ – gerrit Aug 21 '18 at 10:18
  • $\begingroup$ Yeah, what I understand to be the common definition of prefab structures is when they are built from heavily prefabricated pieces which are assembled on-site. Wholesale prefabricated houses are a logical extension of this, but not what I think of when I hear "prefab". $\endgroup$ – Wasabi Aug 21 '18 at 11:44
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One size doesn't fit all.

Putting the US prefab houses mentioned by Muze and blown away by stronger wind, if you go with the european prefab, you can quickly end up with architecture like this: enter image description here photo credit

If you ask anyone living there to list the disadvantages, you won't hear the end of the list. One could say the entire list of advantages consists of "it's affordable to build and maintain," "they can be built fast" and "one can live in there."

The biggest part of the prefab house problem, I think, is lack of individualism. If you make "short runs" of individualized prefabs you're losing the economy of scale; price goes up, list of other disadvantages remains. If you go large scale, it's hard not to end with monolithic, dull, depressing architecture.

Brick offers full flexibility. Fancy curved walls, levels that don't correspond to the integer 'floor#', small quirks, fancy decorative styles, and a house that is tailored to your specific needs. It also doesn't require the sort of heavy machinery heavy prefab construction does. It's extensible, modifiable, can be arbitrarily individualized; plays well with other technologies - wood, steel, glass, aluminum. In short, a brick house can be pretty much anything, from a multi-floor block of flats, to a little fancy castle:

enter image description here

Prefabs don't offer anything near this flexibility. Even room sizes come in small multiples of slab sizes: 1-wide, 2-long bedroom; 2-wide, 2-long living room, 1-wide 1-long bathroom and kitchen, plus half-slab wide, 2-long corridor... it gets depressing.

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  • $\begingroup$ Although I'm not convinced the typically British terraced housing is any more individual than the apartment blocks you linked or than a modern Swedish apartment block and it should be possible to make prefab look more like what I linked from Sweden than what you linked, I recognise the potential flexibility point, which does answer my question. $\endgroup$ – gerrit Aug 18 '18 at 13:56
  • $\begingroup$ To me this looks pretty nice (I don't know if it's prefab, but it certainly isn't individualised, so it could be), but indeed, if you want to individualise each home then prefab won't work. $\endgroup$ – gerrit Aug 18 '18 at 13:59
  • $\begingroup$ @gerrit: Give it 10 years for the paint to fade, sheet metal to show smudges of rust and for dirt to accumulate. $\endgroup$ – SF. Aug 18 '18 at 18:45
  • $\begingroup$ "Why would housebuilders in the UK choose masonry?" is not answered by "flexibility like curved walls, and quirks". Housebuilders build volume, for which they have 3 or 4 different house designs on an estate, and they're all simple. They don't build individual quirky houses. That's what self-builders do. No idea why @gerrit has accepted this as the answer. $\endgroup$ – AndyT Aug 21 '18 at 8:52
  • $\begingroup$ @AndyT: Unless the housebuilders plan several hundred houses of each of these 3-4 designs, economy of scale doesn't justify the choice of prefab. Setting up the production of a new set of prefab parts is costly and will create good returns only for large runs. $\endgroup$ – SF. Aug 21 '18 at 9:29

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