Buying guide

What is a prefab house?

2 min read Updated 2 June 2026

The short answer

A prefab house is a home whose structure is manufactured off site in a factory, then delivered and assembled on a prepared plot. Modern prefab houses are high quality, energy efficient and built far faster than traditional homes. They are a long way from the temporary post war prefabs, and good ones are mortgageable.

Prefab, explained simply

Prefab is short for prefabricated, which means the building is made in sections in a factory rather than entirely on site. Those sections are then transported and assembled on a prepared base, with the home finished far more quickly than a conventional build.

It is the same principle behind modular construction, applied to homes, and it brings the speed, fixed pricing and consistent quality of factory manufacture to housing.

Modern prefab versus the old image

Many people associate prefab with the temporary homes built quickly after the war. Modern prefab is completely different: well insulated, energy efficient, and built to last decades, with finishes that match or exceed traditional homes.

  • High levels of insulation and energy efficiency
  • Quality controlled factory construction
  • Fast assembly on site, often in days
  • Long design lives and structural warranties

Can you mortgage a prefab house?

Modern prefab and modular homes built to recognised standards are mortgageable, though lenders look at the construction type and warranties. A building with a recognised structural warranty and a long design life is treated very differently from an old, non standard post war prefab.

It is always worth checking with a lender or broker who understands modern methods of construction.

Where the Flip fits

The PrefabX Flip is a premium prefab building delivered finished and installed in 2 to 3 days, with a galvanised steel frame, a high insulation specification and a 50 year design life. It works as a self contained home, an annexe, or a garden room, depending on how you use it.

It brings the speed and value of modern prefab without the compromises of the homes that gave prefab its old reputation.

Infographic summarising the key facts: What is a prefab house?
What is a prefab house?

Key takeaways

  • A prefab house is built off site then assembled on a plot
  • Modern prefab is insulated, efficient and built to last
  • It is nothing like the temporary post war prefabs
  • Quality modern prefab homes are mortgageable

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Tell us what you are planning and we will recommend the right Flip layout, confirm your planning position, and give you one all inclusive price. No obligation.

Common questions

Frequently asked

Modern prefab homes built to recognised standards with a structural warranty are mortgageable, though lenders assess the construction type. Older non standard post war prefabs are harder to mortgage, which is a different product entirely.

Modern ones are. Factory construction gives consistent quality, high insulation and long design lives. The Flip is built for a 50 year life with a steel frame and a tested envelope.

Far less than a traditional build. A PrefabX Flip is manufactured off site and installed in 2 to 3 days once the base is ready.

Finance available on every building. Spread the cost and let the bookings pay it back. See finance options

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PrefabX Flip brochure front cover
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