Expelliarmus! Planning inspector orders demolition of giant Harry Potter tree house at £1.2m Hertfordshire mansion

A planning inspector has ordered the demolition of a giant Harry Potter–themed tree house at a £1.2 million mansion in Hertfordshire after months of dispute with neighbours on a leafy millionaire’s row. The structure, built in the garden of Gemma Raval’s gated five-bedroom home, prompted a long-running feud that culminated in a demolition order requiring removal within two months.

Raval erected the 6.5-metre-high tree house last year without planning permission at her property in the quiet hamlet of Rabley Heath, near Welwyn. The dreamlike playhouse features a conical turret, a rope bridge and a slide, and aspiring “enchanted” touches extend to engravings of spells such as Expelliarmus and Stupefy on the rungs of a wooden ladder. Neighbours said that despite not objecting to other improvements on the site, the tree house dominated their boundary and impacted their outlook and use of their gardens.

Welwyn Hatfield Borough Council had rejected planning permission for the structure, describing the scale and height as creating an “unacceptable overbearing impact” on the neighbouring garden. An enforcement notice was issued, ordering demolition, and the owner appealed the decision to the Planning Inspectorate.

Planning inspector Andrew Walker visited the site and dismissed the appeal. He found that the tree house was not actually built in a tree or supported by one, but was a significant self-supported building. His assessment concluded that the sheer bulk and height produced an oppressive presence that undermined the neighbours’ enjoyment of their garden. “There are no conditions which would make the development acceptable,” he wrote in his decision, effectively upholding the enforcement notice and the demolition requirement.

In documents submitted during the retrospective planning process, agents for Ms. Raval had described the structure as a whimsical “Harry Potter-themed castle” designed to delight her daughter and friends, noting plans to plant five evergreen trees and install a two-metre-high fence to mitigate its impact. Council planners, however, argued that the proposed screening would be insufficient and that the neighbouring property should be able to enjoy its own garden without being subject to an unduly dominant addition.

The neighbours who objected told the hearing that the tree house could be seen from all of their back windows and that its proximity to the boundary left them feeling as if their own garden space had been compromised. They argued that meaningfully informing neighbours about such plans is a standard expectation in planning matters, and that not being notified deprived them of a chance to raise concerns before the structure appeared. One neighbour, who asked not to be named, told a local outlet she could now “have a merry Christmas” only after the decision was made, highlighting the personal toll of the dispute.

The case has underscored tensions in affluent areas where ambitious backyard schemes—real or fanciful—sit adjacent to well-established homes. Rabley Heath, described in previous property listings as a picturesque semi-rural enclave near Welwyn village, Codicote and Old Knebworth, sits among similar high-value residences where planning decisions are closely watched by residents and developers alike. The broader urban planning context in Hertfordshire often involves balancing family-friendly amenities and distinctive design with neighbours’ privacy and views, particularly when projects rise suddenly above boundary lines.

For Ms. Raval, the decision marks a decisive moment after a months-long process that began with an enforcement notice and escalated through a Planning Inspectorate hearing. The two-month demolition deadline imposed by the inspectorates’ ruling leaves little room for adjustment, and there is no indication of a further appeal that could alter the outcome. The case serves as a cautionary example for property owners contemplating elaborate garden structures, even those that are whimsical or inspired by popular culture, in areas where neighbours and local authorities are vigilant about preserving sightlines and garden enjoyment.

As the two-month clock starts, observers will be watching whether any last-minute changes to the site or further documentation could influence how such cases are handled in regard to future retrospective applications. The decision reinforces the principle that even highly personalized, well-intentioned family projects must meet the same planning standards as more conventional home improvements when they sufficiently alter the character and use of a garden space.