The report, which profiles trends in UK housing, says shrinking home spaces are down to the inclusion of extra rooms, especially en-suite bathrooms and utility rooms.
Meanwhile, developers are capitalising on the growing popularity of 'town houses' (a house of two, or sometimes three, storeys) and 'mews' homes (a yard or stable converted into housing), by re-branding smaller terraced properties as 'town houses' and 'mews' homes.
The report, by RICS' Building Cost Information Service (BCIS), reveals the trend for more bedrooms per dwelling. It also details the most common types of houses and their most sought after features. It found that the four bedroom detached house was the most common type, making up a third of all homes built and dominating the North of England, Scotland and Wales. Larger, detached, high quality houses are often more profitable for developers.
The fact that UK houses are bought and sold based on number of bedrooms can often be misleading as to a house's actual size and BCIS advocates estate agents referencing houses' floor area, (as in the rest of Europe and the US).
According to BCIS General Manager, Andrew Thompson: "Overall, house sizes have not changed much since the late 80's but market strategy advocates better sales for homes with more bedrooms and bathrooms, even if these are small.
"People today prefer their children to have their own room and more people are working from home which has resulted in a growing trend for additional rooms described as a 'study' or 'home office' in larger homes."
Other trends identified by the report include more three storey dwellings, a growing use of rooms in the roof, an increasing use of bay windows and more garages.