The brief
The client was a private landlord who had purchased a three-storey Victorian terraced house in Hackney with the intention of converting it from a single-family dwelling (Use Class C3) to a six-bedroom House in Multiple Occupation (Use Class C4/Sui Generis). The property had four existing bedrooms across two upper floors, plus a ground-floor reception room and kitchen. The plan was to add two additional bedrooms by subdividing the large first-floor front room and converting the ground-floor reception, with shared kitchen and bathroom facilities on each floor.
The client had been quoted £6,000–8,000 by two local architects for the full drawing set including planning, building regulations, and HMO licensing plans. Our fixed fee of £2,450 covered all three sets of drawings and the planning application submission.
The challenge
Hackney has an Article 4 Direction covering the entire borough that removes permitted development rights for change of use from C3 (dwellinghouse) to C4 (HMO). This means a full planning application was required, unlike boroughs without Article 4 where a change to a small HMO (3–6 occupants) would be permitted development. Three specific challenges shaped our approach:
- Planning policy resistance. Hackney’s Local Plan Policy LP14 restricts HMO conversions where there is already a high concentration of HMOs in the area (more than 20% within 100 metres). We needed to conduct a concentration survey and demonstrate that the local threshold was not exceeded.
- Fire safety — Part B. An HMO with three or more storeys and five or more occupants triggers the “large HMO” regulations. The fire strategy required a protected escape route from every room to a final exit, with 30-minute fire-resistant doors (FD30S), emergency lighting, and an LD2 fire detection system throughout. Our building regulations drawings had to detail every fire door, intumescent strip, and smoke detector position.
- Room size compliance. HMO licensing in Hackney requires minimum room sizes of 6.51 sqm for a single bedroom and 10.22 sqm for a double. Every room had to be measured and annotated on the licensing plans, with ceiling heights confirmed above 2.1 metres for the full floor area to count.
Our approach
We carried out a measured survey of all three floors, recording room dimensions, ceiling heights, window sizes, and the existing fire detection system. We then prepared three drawing sets:
- Planning drawings: Existing and proposed floor plans, elevations, site plan, block plan, and a planning statement addressing Hackney’s HMO concentration policy with our survey evidence showing 14% HMO concentration within 100 metres (below the 20% threshold)
- Building regulations drawings: Fire strategy plan showing the protected escape route, FD30S door schedule, emergency lighting layout, LD2 detection system, Part L energy calculations for the new partitions, and Part E sound insulation specification between bedrooms
- HMO licensing plans: Annotated floor plans with room areas in square metres, ceiling heights, amenity ratios (kitchen facilities, bathrooms, WCs per occupant), and refuse/cycle storage details
For the fire strategy, we worked to BS 9991:2015 and Approved Document B Volume 1. The three-storey layout required a protected staircase with FD30S self-closing fire doors to every habitable room, intumescent strips and cold smoke seals, emergency escape lighting on each landing, and a Grade D1 LD2 detection system with interlinked smoke detectors in the escape route and heat detectors in the kitchen.
The result
Hackney Council validated the planning application within 10 working days. The case officer requested one additional piece of information — confirmation that waste storage for six occupants could be accommodated within the existing front garden — which we provided within 48 hours. Planning permission was granted at week seven with conditions covering refuse management and cycle storage.
The building regulations drawings were approved under a Full Plans application by a private approved inspector. The HMO licensing plans were submitted to Hackney’s Private Sector Housing team alongside the mandatory HMO licence application. The licence was issued following a site inspection after the conversion works were completed.
The conversion cost the client approximately £45,000 for construction (new partitions, fire doors, detection system, kitchen and bathroom fit-out) plus our £2,450 drawing fee. The six-room HMO generates approximately £5,200 per month in rental income, compared to £2,800 as a four-bedroom family let — an increase of £28,800 per year.
