Harry Potter star Rupert Grint will have to install bat boxes inside the storage barn which he plans to convert into three eco-friendly family homes following the discovery of a roost.
The actor, 32, who played Ron Weasley in the iconic film franchise, had originally submitted an application to turn the storage barn in the grounds of his £5.4million 18th century mansion near Kimpton, Hertfordshire, into six homes last year.
But he withdrew the application and submitted a new one for three larger homes after planning chiefs blasted the original proposal for having too many properties.
Following the revised plans, an ecological study commissioned by Grint found that his project would 'disturb and destroy a confirmed bat roost' in his old storage barn.
He will now have to install alternative bat boxes for the creatures on his 22-acre land before any building work starts.
Rupert Grint, who wants to convert his barn into three eco-friendly homes, has conjured up a series of conservation measures to protect the bats in his storage barn, near Kimpton, Hertfordshire
After an ecological study commissioned by Grint found that his project would 'disturb and destroy a confirmed bat roost' in his barn he proposed a series of conservation measures. Pictured: The inside of Grint's barn seen in planning documents
The actor, who is currently starring in the Apple TV drama Servant, is also proposing that his construction project only takes place under the guidance of wildlife experts
Grint is also proposing that his construction project only takes place under the guidance of wildlife experts at times when bats are least vulnerable to harm and disturbance.
The actor had originally submitted an application to turn the barn into six homes but withdrew the application and submitted the new one for three larger homes.
Matt Dodds, of the Hertfordshire and Middlesex Wildlife Trust, claimed soon after the plans were submitted in March that not enough detail had been given about protecting bats.
He called for 'a full ecological survey' to assess what actions were needed to protect bats if the development was going to be approved by North Hertfordshire District Council.
Consultant ecologist Adam Lewins responded to the concerns on behalf of Grint by detailing the protection measures that the actor planned to take.
Mr Lewins, a director of Wiltshire-based Kingfisher Ecology, stated that the star would apply for a European Protected Species Mitigation Licence to ensure bats were protected.
He said that any such licence would require 'a method statement' and 'work schedule' to 'ensure the proposed works on the property will not be detrimental to the range of bat species'.
Mr Lewins added in a planning document that the actor would be carrying out a more detailed survey to find out more about the numbers and type of bats in the barn and their foraging habits.
Grint hopes to convert the barn (in red), which is unused and located away from the main house and cottages on the estate (in blue), into three eco-friendly homes
Planning documents show that all mature trees and hedges around the barn will be retained where possible and landscape enhancements for foraging bats will be incorporated into the landscape design strategy. Pictured: The actor's driveway
The statement accompanying his planning application to convert his barn, states that the three proposed house will be 'of high-quality design and in keeping with the rural surroundings'
The converted properties will maintain the character and appearance of the Kimpton Bottom Conservation Area
Each of the new houses will have a 'spacious' open-plan living and dining area with en-suite bathrooms, private gardens and car parking spaces
He said the survey would identify a 'detailed bat roost compensation' scheme which would have to be approved by Natural England.
The scheme will involve the installation of 'alternative roosting opportunities' in bat boxes in suitable locations within the curtilage of the site before any construction work starts.
Mr Lewins added in a letter to the council: 'The works will be undertaken when bats are least likely to be present and at times of year when they are least vulnerable to harm and
