A third of parents are giving up their master bedrooms to accommodate their children in space-starved family homes.
Around 31) of the 2,000 families who were questioned for the survey said several of their children share bedrooms.
Over half of the parents questioned (58) aspiring to move to a larger house for more space.
The findings come as figures from the Royal Institution of Chartered Surveyors show the average size of a family home has decreased dramatically over the last 90 years.
An average family home has decreased from 1,647 square feet 90 years ago to just 925 square feet today.
Commenting on the findings, John Willcock, head of mortgages at the Post Office, said: "With the average house size continuing to shrink, and with many family homes often lacking a garden, it's hardly surprising that so many of us are concerned about this lack of space and the impact it will have on our children.
"Unfortunately, the reality of the situation means a lot of families feel like they're letting their children down by not being able to provide them with their own room, or playroom where they can study or play.
"As a result a number of parents are making sacrifices and giving up larger rooms in the home to children."
Have you had to reorganise your family home to make the most of space recently? Please do share your stories...
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