Gaining permission for annexes linked to Houses in Multiple Occupation (HMOs) can be challenging. Local authorities often scrutinise whether such proposals risk creating independent dwellings, raise parking pressures, or negatively impact neighbouring amenity. In this case, the application sought approval for a modest detached annexe within the garden of an existing HMO, raising several sensitive planning issues.
A central question was whether an annexe can be lawfully treated as ancillary to an HMO use rather than a single family home. Objections also centred on the potential for increased parking demand, with concerns from the parish council that an additional bedroom could intensify occupation. The design also needed to demonstrate subordination to the main dwelling, whilst providing flexible accommodation that could be reintegrated into the host property in future.
NAPC prepared a detailed planning case addressing each of these matters. Using relevant appeal precedents, it was demonstrated that an annexe can remain ancillary to an HMO where there is a clear functional link. This was supported by the proposed dependency on shared kitchen facilities and restrictions on independent access, utilities, and curtilage. The design was carefully managed to remain modest in scale and typical of garden outbuildings, ensuring it was visually subservient to the host building and in keeping with the character of the area.
Concerns over parking were addressed by highlighting the lawful use of the property as a small HMO, which already permits occupation by up to six residents. Highways officers confirmed that the proposal did not create a severe impact on local roads, subject to conditions requiring cycle storage to promote sustainable travel. Neighbouring amenity was safeguarded by the building’s single-storey height, preventing overlooking, loss of light or dominance. With the footprint falling below the threshold for mandatory biodiversity net gain, there were no ecological constraints.
The local planning authority concluded that the proposal complied with both local and national policy. Permission was granted subject to conditions ensuring the annexe remains ancillary to the host property and that sustainable transport measures are delivered.
This success illustrates how annexes associated with HMOs can be approved when supported by a strong planning strategy. By addressing policy requirements on design, transport, and amenity at an early stage, it is possible to overcome local objections and secure valuable additional accommodation.
