HMO Conversion Drawings in Sidcup DA15
Fixed-fee, MCIAT-chartered hmo conversion drawings for Sidcup (DA15) homeowners — London Borough of Bexley validation and local constraints handled from the start.
Sidcup's DA15 stretches north and west from the town toward Blackfen, Lamorbey and Longlands, mixing broad inter-war suburban avenues with older hamlets along Halfway Street and Burnt Oak Lane. Side-return, rear and loft extensions on the 1930s semis are the everyday work, but two designated conservation areas change the rules on specific streets.
The Halfway Street Conservation Area, designated in 1985, protects some of the oldest cottages in the borough around Holy Trinity Church, while the Longlands Road Conservation Area of 1992 guards an almost unaltered inter-war estate. Both carry Article 4 Directions, so alterations that are automatic elsewhere in DA15 need a full application within their boundaries.
Planning in Sidcup (DA15): what to know before you apply
Within the Halfway Street and Longlands Road conservation areas the Article 4 Directions withdraw permitted development for elevation, roof, window and front-boundary changes, so alterations that are automatic on nearby 1930s streets need a householder application here. Elsewhere in DA15 — the wider Blackfen, Lamorbey and Longlands suburbs — rear and loft extensions on the inter-war semis commonly remain permitted development, subject to the usual size and height limits.
Typical Sidcup housing stock
Sidcup's DA15 stock runs from some of the oldest houses in the borough — the 17th- and 18th-century cottages lining Halfway Street and Burnt Oak Lane — to the almost unaltered inter-war semi-detached estate of Longlands Road, with broad Edwardian and 1930s suburban avenues around Blackfen and Lamorbey in between.
Streets we regularly draw for in Sidcup
Halfway Street · Burnt Oak Lane · Longlands Road · Blackfen Road
What DA15 is actually built of
Measured from 387 classified residential buildings in DA15, not from a description of the area.
Sidcup DA15 housing mix
Residential building form across the DA15 postcode district, from 387 classified buildings.
| Attached on more than one side | 42% |
|---|---|
| Attached on one side | 50% |
| Detached | 8% |
| Median building footprint | 67 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 1.04 |
| Buildings classified | 387 |
Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-08-17.
HMO Conversion Drawings for Sidcup (DA15) homes: the package and the process
An HMO scheme is drawn against a schedule. Every bedroom is dimensioned with its usable floor area stated, shared kitchen and bathroom provision is counted against the number of occupants, and the layout has to hold up against the space standards the licensing team applies.
The fire strategy is drawn, not described: protected escape route, fire doors and their ratings, alarm coverage by room, and compartmentation between floors. Licensing and building control assess the same drawing set from different angles, so it has to satisfy both without contradiction.
Room count is a function of the existing plan. A large semi or detached house with generous rooms can meet the space standards without subdivision, while a narrow terrace usually cannot reach the same occupancy without creating rooms that fall below the minimum floor area.
C4 small HMO or sui generis large HMO — which applies to your property?
The distinction matters because it decides which rules apply. A small HMO housing three to six unrelated sharers who share amenities is Class C4. A large HMO of seven or more occupants is sui generis and always needs planning permission, since sui generis uses sit outside the permitted development system entirely. The line also shifts with occupancy — a property let to six sharers today can tip into sui generis territory the moment a seventh tenancy is signed, which changes the planning position even though nothing about the building itself has changed. We assess your proposed occupancy and layout against both definitions before drawing, so the application matches how the property will actually be let.
Do I need planning permission for an HMO conversion in London?
Converting a family home (C3) into a small HMO (C4) is technically permitted development under national rules, but a large number of London boroughs have made an Article 4 direction that removes this right across all or part of the borough — meaning a full planning application is required even for a small, compliant HMO. Article 4 directions vary street by street in some boroughs, so two similar houses a few doors apart can sit on opposite sides of the line. Any large HMO (sui generis) needs planning permission everywhere, regardless of Article 4. We check your specific address against the relevant borough's Article 4 direction before recommending a route, since guessing wrong wastes both time and application fees.
Mandatory and additional HMO licensing — what's required?
Most HMOs need a licence from the council, separate from any planning permission. A licence application typically has to demonstrate that the property meets fire safety, amenity and space standards, that gas and electrical installations are safety-certified, and that the landlord or managing agent is a fit and proper person to hold it.
Mandatory licensing
Applies to any HMO of five or more occupants forming two or more households, regardless of the number of storeys — a national requirement in every London borough.
Additional licensing
Many boroughs extend licensing to smaller HMOs, typically three or four occupants, across all or part of their area. We check the current scheme for your borough before you apply, since schemes and boundaries change.
| Factor | C4 small HMO (3–6 sharers) | Sui generis large HMO (7+) |
|---|---|---|
| Use class | C4 | Sui generis |
| Planning permission | Often needed due to Article 4 directions in most boroughs | Always needed |
| Licensing | Mandatory if 5+ occupants; additional licensing in many boroughs | Mandatory |
| Typical drawing package | From £1,400 | Full planning + building regs, from £2,200 |
HMO Conversion Drawings in Sidcup DA15 — FAQs
How much do HMO conversion drawings cost in London?+
Is HMO conversion permitted development in London?+
Do I need a licence as well as planning permission?+
Do I need an architect for an HMO conversion?+
How long do HMO conversion drawings take?+
Do I need planning permission for an extension in Bexley?+
Can I build a bigger extension because Bexley plots are larger?+
What extra control applies in Old Bexley Village or around Danson Park?+
How long does Bexley Council take to decide?+
How much do planning drawings cost in Bexley?+
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