A homeowner may be forced to tear down his decking and extension after a council used Google Earth images to rule they were illegal.
Colin Thomas, 65, tried to use a loophole in planning law to keep the two structures at the front and rear of his house in Portland, Dorset.
He did not obtain planning permission for the works after thinking they came under "permitted development rights" for homeowners.
But Dorset council rejected Thomas' application after using Google pictures to determine the two structures did not meet the rules.
Thomas applied to the local council to make the structures lawful under the rule that recognises any changes to a property that have been in place for four years are exempt from enforcement action.
He and a friend and builder stated the 20ft by 16ft raised decking at the front of his house and the single-storey rear extension were built soon after he bought the property in 2012.
But Dorset planning officer Thomas Wild determined this was not the case when he looked up the property on Google Earth and Google Street View.
He found the images of the rear extension and the current decking were absent in the satellite photos of the terraced house taken in September 2020.
He concluded: "Therefore...it does allow for a conclusion that the rear extension was constructed between September 2020 and June 2022.
"Therefore it has been present for less than four years and has not achieved immunity from enforcement action on that basis."
Wild also spotted the raised deck at the front of the house in Google photos taken in 2016 and 2021 but found it was a different decking to the one today.
He said the original decking was timber but the present structure is made from composite boards that have been topped with artificial grass.
Wild also worked out that the replacement decking was bigger than the original.
He added: "Although it accepted that by around 2016 the original timber decking had become immune from enforcement action, that immunity was lost when the decking was removed.”
As a result, Dorset Council refused Mr Thomas's application and he now faces the prospect of demolishing both the rear extension and the raised decking.
A spokesperson for Dorset Council said: "There is an ongoing enforcement investigation for the site and the next step will be to consider the expediency of taking enforcement action against the works. The applicant will have a right of appeal against the decision and any enforcement notice."
What can I build without planning permission?
Some projects do not require planning permission due to 'permitted development rights'.
Building projects that usually have permitted development rights include industrial premises and warehouses, some outdoor signs and advertisements and demolitions.
There are other projects that might not need planning permission - for example, projects that will have no impact on your neighbours or the environment.
If you think this could apply to your project, check with your local planning authority through your local council.
The roll-out of permitted development rights has drawn some criticism. Housing charity Shelter warned in 2019 that extensive use of permitted development rights (PDR) had meant local authorities cannot determine whether a scheme is of an acceptable quality to go ahead, or whether it is safe.
According to industry magazine The Developer, the House of Lords recently voted through an amendment to the Levelling Up and Regeneration Bill that would ensure new homes built under PDR would meet a minimum 'healthy homes' requirement amid fears than many of the 100,000 dwellings created in the past 10 years lack adequate safety features.
Read more: House of Lords back standards to tackle unhealthy PDR homes (The Developer)
How do I get planning permission?
Planning permission may be required if you're considering building something new, making significant changes to your existing building, such as adding an extension, or changing the use of your building.
If your project requires planning permission and you proceed without obtaining it, you risk being served an 'enforcement notice' which would require you to undo all the changes.
Ignoring an enforcement notice is illegal but you have the option to appeal against it.
To apply for planning permission, contact your local planning authority through your local council.
Read more: Rules on planning permission in the UK (Gov.UK)