Planning permission was granted on 6 October 2025 for the erection of a replacement dwelling with annex accommodation following demolition of the existing dwelling and annexe.

Amended plans were submitted which revised the design of the dwelling and relocated the replacement dwelling further from the lake than the existing house and to the southwest of its original proposed position.  

The case officer in her delegated report concluded

• The site is in a remote rural setting, within the open countryside and in the CA2 Agricultural Belt Character Area, as defined in the Copthorne Neighbourhood Plan.
• Lake House is a detached house on a 0.23-hectare site, located in a rural location on the eastern side of Old Hollow. The house and associated annexe are accessed via a private driveway, off a shared access road.
• The existing house has a traditional two storey appearance with dark stained horizontal wooden clad walls, pitched roofs finished with plain tiles and white windows.
• The proposed new dwelling is located partly over the existing building footprint, with the living accommodation located on two floors. The proposed new dwelling has an H shaped footprint and is sited further away from the lake than the annexe. The position of the proposed house will allow for the retention of the existing circular driveway to the front of the existing house, with the associated trees which characterise the approach.
• The proposed new dwelling has a maximum ridge height of 7.9m, with eaves at 4.8m, and the ridge height on the annexe reaches 5.2m in height, with the eaves at 2.3m in height. The proposed house is orientated differently, with a greater building depth to the existing house, with a new, contemporary design.
• The proposed new house would have a floor area 590 square metres. The existing dwelling and annexe have a floor area of 476 sq m, although the permitted extensions would increase this to 598 sq m. The replacement house would therefore represent a 24% floorspace increase over the existing but would be 8.5 sq m smaller than the house, if it were enlarged as permitted.
• The proposal is acceptable in principle as it is for a one for one replacement dwelling that accords with District Plan Policy DP15.
• The design, external materials and scale of the proposed dwelling are considered appropriate.
• Whilst the views of the Conservation Officer are understood it is considered that due to the significant distances which separate the site from the listed buildings at Rowfant Mill and Ley House and it is not considered that the new dwelling will impact on the setting of the nearby Listed Buildings.

Other topic areas that were considered included. 

• Highway access and parking considerations

• Impact on neighbouring amenity
• Heritage considerations
• Space standards compliance
• Ecology and biodiversity
• Sustainability
• Recreational disturbance
• Atmospheric pollution
• Flood risk and drainage 
• Renewable and Low Carbon Energy

The officer report showed full policy compliance with these topic areas. 

The permission granted was subject to 18 planning conditions. 

Details of the application can be found on the Mid Sussex District Council planning application search website. Reference no DM/24/2263.