# a house built on sand

idiom · CEFR C1

Source: https://englishreference.com/idiom/a-house-built-on-sand
Updated: 2026-07-29

## Meaning

A plan or venture with no solid foundation, liable to collapse under pressure.

## Examples

- Their plan was a house built on sand.
- The whole scheme was a house built on sand, funded entirely by loans it could never repay.
- Growth looked spectacular until the first downturn revealed a house built on sand — no cash reserves, no loyal customers, nothing beneath the numbers to hold the whole thing up.

## Origin

The phrase closes the Sermon on the Mount. In Matthew 7:26-27, Jesus contrasts two builders: the wise man builds his house on rock, and it stands through the storm; the foolish man builds on sand, "and the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell: and great was the fall of it." The lesson in context is about foundations of a spiritual kind — hearing wise words and acting on them. But the picture is concrete and universal: anything built on shifting ground will not survive the first serious test. English took the image straight. A house built on sand is any undertaking that looks fine until it is tested — a business without real revenue, a relationship without trust, an argument without evidence — sound in fair weather, doomed in a storm.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.