Sites with room for almost 200,000 homes are missing from official registers of brownfield, according to research by the Campaign to Protect Rural England (CPRE). These include former builders’ yards, disused warehouses and blocks of garages no longer used for parking.

The government says that it has a “brownfield first” policy when identifying land for more homes. To help to achieve this it has ordered all councils in England to publish registers by the end of this month of brownfield land suitable for development.

The CPRE examined 43 of the registers already published and found that only 4 per cent of the brownfield land they identified was on small sites that could accommodate up to ten homes.

In the budget last month the government announced that it wanted councils to identify enough small sites to provide 20 per cent of the new homes needed.

Philip Hammond, the chancellor, also said that the government would “ensure that our brownfield and scarce urban land is used as efficiently as possible”.

The CPRE found that if councils met the 20 per cent target on small brownfield sites, an additional 189,000 homes could be built in England.

It asked a sample of local authorities how they identified land for their brownfield registers and found that they “routinely disregarded small brownfield sites”.

Councils overlooked the sites even though they usually had infrastructure in place, such as rail and road links and schools and hospitals, which were less likely to be available for greenfield sites.

The reasons given by councils for not listing small brownfield sites included that they lacked the resources to identify them and that housebuilders did not favour them because of the perception that the planning system was too burdensome for small plots.

The CPRE said that the failure to identify small brownfield sites was resulting in councils allocating land for development in the green belt, the protected land around 14 cities.

It has called on the government to amend official guidance to ensure that councils identified all the available brownfield sites in their areas.

Rebecca Pullinger, CPRE’s planning campaigner, said: “Up and down the country tens of thousands of small brownfield sites are not included in brownfield land registers and their housing development potential missed.

“The current system of collecting this data must be improved if we are to unlock the potential of brownfield and stop developers finding an excuse to build on greenfield areas.”