Haringey Extensions 2026: Planning Guide, Costs & Permitted Development
Everything you need to know about extending your home in Haringey. 28 conservation areas, a partial Article 4 direction on HMO conversions, Local Plan policy, and 2026 costs.
TL;DR - The Quick Answer
Haringey has 28 conservation areas, covering large parts of Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green, plus a run of smaller designations across Tottenham and Wood Green. Conservation area status alone restricts some permitted development rights nationally, and four conservation areas (Noel Park, Peabody Cottages, Rookfield Estate, Tower Gardens) carry their own Article 4 direction removing further rights such as window and door alterations. Separately, a partial Article 4 direction covering 14 wards in the east and centre of the borough removes permitted development rights for converting a house into a small HMO, in force since 30 November 2013. Extensions are assessed against Policy DM12 (Housing Design and Quality) and, in conservation areas, Policy DM9 (Management of the Historic Environment). A householder planning application costs £548 and a lawful development certificate costs £274. Standard applications take 8 weeks.
Haringey: What Kind of Borough Is It?
Haringey is a north London borough stretching from the leafy slopes of Highgate and Muswell Hill in the west to the denser urban fabric of Tottenham and Wood Green in the east. The contrast between these two halves is pronounced and has a direct bearing on planning for home extensions.
Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green are dominated by Victorian and Edwardian terraces and semis - bay-fronted properties in original stock brick, with slate roofs and typical London rear gardens. These areas are among the most sought-after in north London and carry a high concentration of conservation area designations, some dating back to the 1960s and 1970s. In these streets, a large proportion of the borough's period housing stock sits within a conservation area, which is the single most important thing to establish before starting any extension project.
Tottenham and Wood Green, in the east, have a more mixed housing stock. Victorian terraces sit alongside inter-war council estates, 1930s semis, and post-war development. Conservation area coverage here is more selective, focused on specific corridors such as the Tottenham High Road Historic Corridor and the Noel Park estate, rather than blanketing whole neighbourhoods as it does in the west. The same eastern half of the borough is where Haringey's partial HMO Article 4 direction is concentrated, a separate and easily confused designation covered in detail below.
Haringey Local Plan and Extensions Policy
The current adopted Haringey Local Plan comprises the Strategic Policies, adopted in 2013 and altered on 24 July 2017, and the Development Management DPD, adopted on the same date. Together with the Site Allocations DPD and the Tottenham and Wood Green Area Action Plans, these documents form the development plan against which all householder planning applications in Haringey are currently assessed.
Extensions and alterations to existing houses are governed principally by Policy DM12 (Housing Design and Quality), whose "Residential Extensions" criteria require extensions to be of a high, site-specific and sensitive design quality, responding to the form, setting, period and detailing of the original building, using matching or complementary materials. Full-width rear extensions are not normally considered acceptable, and any extension should be subordinate to the main house, lower than the ridge height, and should not cause an unacceptable loss of daylight, sunlight, privacy or outlook to neighbouring properties. Roof extensions such as dormer windows should be restricted to the rear; front dormers are not normally permitted unless they are already part of the established local character. Proposals are also expected to have regard to relevant supplementary guidance, including the South Tottenham House Extensions SPD.
Where a property sits within a conservation area, Policy DM9 (Management of the Historic Environment) applies alongside DM12. Its criterion on alterations and extensions requires proposals to complement the style, scale, proportions, materials and detailing of the host building, and not to appear overbearing or intrusive. The supporting text to DM9 records that Haringey has 28 conservation areas, 471 statutory listed buildings, and 1,150 locally listed buildings of merit - a useful indication of how much of the borough's built fabric is subject to heritage-led design scrutiny.
Haringey is currently preparing a new Local Plan. Under the council's Local Development Scheme, approved by Cabinet in March 2025, a Regulation 19 Proposed Submission consultation ran in May and June 2026, with submission to the Planning Inspectorate and examination timetabled for July to November 2026 and adoption targeted for February 2027. Until the new plan is adopted, the 2013/2017 Strategic Policies and the 2017 Development Management DPD remain the policies that apply to your extension application today.
Haringey's Partial HMO Article 4 Direction
Separately from its conservation areas, Haringey has made an Article 4 direction covering houses in multiple occupation (HMOs). It removes the permitted development right that would otherwise let a homeowner change a property from a single dwelling (use class C3) to a small HMO housing three to six unrelated occupants (use class C4) without planning permission. Unlike Enfield's equivalent, which is borough-wide, Haringey's direction is partial: it applies to 14 specific wards rather than the whole borough, and the council describes it as covering "most of the east of the borough."
The direction has been in force since 30 November 2013 and covers the following wards: Bounds Green, Bruce Castle, Harringay, Hermitage and Gardens, Northumberland Park, Noel Park, St Ann's, Seven Sisters, South Tottenham, Tottenham Central, Tottenham Hale, West Green, White Hart Lane, and Woodside. Any HMO conversion within these wards must also comply with Policy DM17 of the Development Management DPD. Outside these 14 wards, including much of the western half of the borough around Crouch End, Muswell Hill, and Highgate, a C3 to C4 HMO conversion may still proceed under permitted development, subject to the usual national limits.
Why this matters if you are extending
- The HMO Article 4 direction affects a change of use, not the physical extension itself. A standard family extension is unaffected regardless of ward
- If you are extending a property within one of the 14 wards with the intention of letting rooms individually to unrelated sharers, you will need a separate change-of-use planning application alongside any consent for the building work
- Noel Park sits in both lists: it is a conservation area with its own Article 4 direction on external alterations, and its ward is also covered by the separate HMO Article 4 direction. The two designations address entirely different things and both can apply to the same property
- Large HMOs of seven or more occupants always need planning permission everywhere in London, because they fall outside permitted development as sui generis use regardless of any Article 4 direction
For a wider comparison of how HMO Article 4 directions vary across London, see our Article 4 and HMO borough guide.
Conservation Areas in Haringey
Haringey's definitive list of conservation areas names 28 designated conservation areas, the oldest being Highgate (designated 1967) and the most recent being Vallance Road in Tottenham (designated 2008). Several sit in the most popular residential parts of the borough - Crouch End (1974), Muswell Hill (1974), Fortis Green (1974), and Stroud Green (2003) - meaning a large share of the borough's Victorian and Edwardian housing stock falls within a conservation area boundary.
Conservation area status alone already restricts some permitted development rights nationally - notably cladding to external walls and some roof alterations - even where no specific Article 4 direction has been made. On top of that baseline, Haringey has made four Article 4 directions within conservation areas that remove further rights, such as alterations to windows and doors: Noel Park, Peabody Cottages, Rookfield Estate, and Tower Gardens. Crouch End, Muswell Hill, Highgate, and Stroud Green do not currently carry their own additional Article 4 direction, though the general conservation area restrictions and Policy DM9's design tests still apply in full to any extension in these areas.
Crouch End Conservation Area
The Crouch End Conservation Area, designated in 1974, covers the core of this popular neighbourhood, including the Broadway and the surrounding Victorian streets. The area is characterised by late-Victorian terraces and semis - typically bay-fronted two-storey properties in yellow London stock brick, with original sash windows, slate roofs, and front boundary walls. Extensions here require planning permission in most cases (rather than a specific Article 4 direction, since Crouch End does not have one of its own), and officers will expect proposals to respect the scale, materials, and character of the existing building under Policy DM9.
Muswell Hill Conservation Area
Muswell Hill has a distinctive Edwardian character, with the shopping Broadway and surrounding residential streets developed largely between 1896 and 1914. The residential streets - Muswell Road, Queens Avenue, Alexandra Park Road - contain Edwardian terraces and semis with red brick and render facades, bay windows, and prominent rooflines. The conservation area character appraisal emphasises the importance of retaining the consistent street pattern and the rhythm of gable features and bay windows. Rear extensions are the most common project type here and can be approved where they are appropriately scaled and use sympathetic materials.
Highgate Conservation Area
Highgate, designated in 1967 and the oldest of Haringey's conservation areas, is one of the borough's most sensitive, with a concentration of Georgian and early Victorian buildings around Highgate Village. The area straddles the boundary with Camden, and some properties fall within Camden's planning jurisdiction rather than Haringey's. For properties within Haringey's portion of Highgate, the design bar is high - extensions must be of the highest quality, demonstrating a clear understanding of the historic context. Pre-application engagement with Haringey officers is strongly recommended before any work in this area.
Other conservation areas
| Conservation Area | Designated | Own Article 4? |
|---|---|---|
| Highgate | 1967 | No |
| Fortis Green | 1974 | No |
| Crouch End | 1974 | No |
| Muswell Hill | 1974 | No |
| Rookfield (estate) | 1976 | Yes |
| Alexandra Palace and Park | 1978 | No |
| Tower Gardens | 1978 | Yes |
| Noel Park | 1982 | Yes |
| Peabody Cottages | 1991 | Yes |
| Stroud Green | 2003 | No |
| Vallance Road | 2008 | No |
A further 17 conservation areas make up the remainder of the borough's 28, including the five that form the Tottenham High Road Historic Corridor (North Tottenham, Scotland Green, Bruce Grove, Tottenham Green, and Seven Sisters/Page Green). Always verify the status of your specific property using Haringey's Article 4 directions page before assuming permitted development rights do or do not apply.
Noel Park: a conservation area with a specific character
The Noel Park Conservation Area in Wood Green (N22), designated in 1982, is one of Haringey's most distinctive. Built in the 1880s as a planned working-class estate by the Artisans, Labourers and General Dwellings Company, the streets are characterised by consistent red brick terraces, decorative terracotta detailing, and a coherent estate layout. Its own Article 4 direction removes further permitted development rights on top of the standard conservation area restrictions. Extensions here require particular care - the uniformity of the original design means any intervention is highly visible - and planning permission is required, with officers expecting proposals to be sympathetic to the estate's distinctive character.
Permitted Development in Haringey
Where a property is outside a conservation area and not subject to the HMO Article 4 direction - primarily in the more suburban or post-war parts of the borough such as parts of Tottenham, Wood Green, and Bounds Green - the standard national permitted development rules for householders apply. Within any conservation area, some permitted development rights are automatically restricted by the designation itself, notably cladding and certain roof alterations, regardless of whether a specific Article 4 direction has also been made.
| Extension Type | Max Without Permission | Haringey Notes |
|---|---|---|
| Single-storey rear (detached) | 4m deep, 4m high | Check conservation area status before assuming PD |
| Single-storey rear (semi/terrace) | 3m deep, 4m high | Not applicable in most conservation area streets |
| Large rear extension (prior approval) | Up to 8m (detached) or 6m (semi/terrace) | Neighbour consultation required; not in conservation areas |
| Side extension | Half width of house | Rarely applicable in Haringey conservation areas |
| Two-storey rear | 3m deep max | Almost always requires planning permission |
| Loft conversion (dormer) | Max 40m³ (terraced) or 50m³ (semi/detached) | Requires planning in all conservation areas |
Key Restrictions to Know
- Conservation area designation alone removes the right to clad external walls and restricts some roof alterations - even without a specific Article 4 direction
- Listed buildings require listed building consent in addition to any planning permission. Haringey's Development Management DPD records 471 statutory listed buildings and 1,150 locally listed buildings of merit, with a concentration in Highgate
- Tree Preservation Orders (TPOs) are widespread in Haringey, particularly in Highgate, Muswell Hill, and Alexandra Park - check before any groundworks
- Highgate straddles the Haringey/Camden boundary - check which borough applies to your specific property before submitting any application
Loft Conversions and Roof Alterations
Loft conversions are one of the most popular projects on Haringey's stock of Victorian and Edwardian terraces, where the existing roof pitch often gives useful head height to work with. Outside conservation areas, a dormer loft conversion on a house is generally permitted development, subject to the national volume limits of up to 40m³ on a terraced house or 50m³ on a semi-detached or detached house, with the usual conditions on materials, side-facing windows, and set-back from the eaves.
Within any of Haringey's 28 conservation areas, dormer loft conversions require planning permission rather than proceeding as permitted development. Policy DM12 is explicit that roof extensions should be restricted to the rear, and that front dormers are not normally permitted unless they are already part of the established local character of the street. This is a common source of refusal in Crouch End and Muswell Hill, where the consistent rhythm of original rooflines is a defining part of each conservation area's character appraisal, so a front dormer that would be routine elsewhere can be resisted here.
Extension Types by Neighbourhood
Crouch End and Stroud Green (N4, N8)
The narrow Victorian terraces of Crouch End and Stroud Green have a side passage alongside the ground floor that is one of the most valuable spaces available for extension. Infilling this side return - typically 1.2m to 1.8m wide and running the full depth of the ground floor - creates an L-shaped footprint that dramatically improves the kitchen and dining layout. Combined with a rear extension, this wraparound approach is the most sought-after project type in these streets. Officers expect materials to either match the original building fabric or take a clearly contemporary approach using high-quality contrasting materials at the rear, provided the contrast is handled with care.
Muswell Hill (N10)
Muswell Hill's Edwardian properties tend to have slightly larger footprints and more generous rear gardens than Crouch End's Victorian terraces. Loft conversions are common here, since the larger original roofspaces lend themselves to dormer conversions, but a dormer visible from the street requires planning permission within the conservation area and is generally supported only where it sits to the rear and does not disrupt the roofline. Single-storey rear extensions, typically 3m to 4m deep with a full-width glazed rear opening, remain the most common project.
Highgate and Hornsey
Highgate's Georgian and early Victorian buildings sit at the top of the borough's design hierarchy, and any extension needs a clear justification against the historic context, particularly given the concentration of listed buildings. In Hornsey, split between the Hornsey High Street (1980) and Hornsey Water Works and Filter Beds (1994) conservation areas, and the nearby Alexandra Palace and Park conservation area (1978), extensions are assessed with particular reference to views to and from Alexandra Palace, which the character appraisals identify as an important part of the setting.
Noel Park
The Noel Park Conservation Area presents particular constraints because of its own Article 4 direction and the uniformity of the original estate design. Rear extensions invisible from the public realm can be approved, but any alteration visible from the street requires a high standard of design justification. Homeowners here are strongly advised to seek pre-application advice before commissioning detailed drawings.
Tottenham and Wood Green (N15, N17, N22)
Outside the conservation areas, the Victorian terraces of Tottenham and the more mixed housing stock of Wood Green often operate under standard permitted development rules. For a semi-detached or terraced property in, say, Bruce Grove or West Green Road outside a conservation area, a single-storey rear extension of up to 3m depth may be possible without planning permission, subject to the usual height and materials conditions. The one thing to check carefully here is the HMO Article 4 direction: several of these same streets sit within one of the 14 wards where converting the property to a small HMO needs planning permission, even though a standard family extension does not.
The Planning Process in Haringey
Standard householder planning applications in Haringey are decided within 8 weeks of validation. Most householder extension applications are decided by officers under delegated powers and do not go to committee. Haringey offers a fast-track service for householder and lawful development certificate applications, which can reduce the decision period for straightforward cases.
Pre-application advice
Haringey provides a pre-application advice service for householders. Current fees (all include VAT):
- General advice: £103
- Express written planning advice (no meeting): £312
- Planning advice, with a meeting: £498
- Property with a basement: £852
- Out-of-office visit: £240, added to the fee for the relevant service
Pre-application advice is strongly recommended for extensions in Crouch End, Muswell Hill, Highgate, and any conservation area with its own Article 4 direction (Noel Park, Peabody Cottages, Rookfield Estate, Tower Gardens). Officers will indicate what scale, design, and materials they are likely to support, reducing the risk of a refusal that delays your project by months.
Application fees (2026)
- Householder application: £548 (national fee, following the 2026 CPI-linked increase)
- Lawful development certificate: £274
- Listed building consent: No charge (fee-exempt)
Extension Costs in Haringey 2026
Our London extension costs guide puts London-wide construction costs at £3,200-£4,600 per m² in 2026, with Inner London boroughs such as Islington, Hackney, and Camden running 5-15% above that range and Outer London running 5-10% below it. Haringey sits across both categories: the western half of the borough - Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green - tracks toward the Inner London differential, while Tottenham and Wood Green track closer to the Outer London baseline. All figures below include VAT at 20% and are derived by applying that position to the London-wide bands, not independent Haringey-specific project data.
| Extension Type | Typical size | Construction cost (inc VAT) | All-in estimate |
|---|---|---|---|
| Single-storey rear extension | 3m x 5m (15m²) | £48,000-£75,000 | £58,000-£90,000 |
| Side return extension | 2m x 8m (16m²) | £43,000-£67,000 | £52,000-£80,000 |
| Loft conversion (dormer) | 25-35m² | £50,000-£77,000 | £60,000-£92,000 |
| Two-storey rear extension | 3m x 5m per floor (30m²) | £83,000-£129,000 | £100,000-£155,000 |
| Wraparound extension | Rear + side return, 25-35m² | £75,000-£115,000 | £90,000-£138,000 |
Note: figures are derived by applying Haringey's position within the London-wide bands in our costs guide (west Haringey tracking the Inner London differential; Tottenham and Wood Green tracking closer to the Outer London baseline), not independent Haringey-specific project data.
Conservation area premium: Add 5-10%, per our costs guide, for any of Haringey's 28 conservation areas, to cover matching materials and additional design work.
| Extension Type | Typical size | Construction cost (inc VAT) | All-in estimate |
|---|---|---|---|
| Single-storey rear extension | 3m x 5m (15m²) | £48,000-£75,000 | £58,000-£90,000 |
| Side return extension | 2m x 8m (16m²) | £43,000-£67,000 | £52,000-£80,000 |
| Loft conversion (dormer) | 25-35m² | £50,000-£77,000 | £60,000-£92,000 |
| Two-storey rear extension | 3m x 5m per floor (30m²) | £83,000-£129,000 | £100,000-£155,000 |
| Wraparound extension | Rear + side return, 25-35m² | £75,000-£115,000 | £90,000-£138,000 |
Source: Derived from Mayfair Studio London extension costs guide 2026 • Data as of 2026
Additional professional and statutory costs
- Design team (drawings, specification, contract admin): £4,500-£14,000 (typically 8-12% of build cost)
- Structural engineer: £1,500-£3,500
- Planning application fee: £548 (householder)
- Lawful development certificate: £274 (if applicable)
- Party wall surveyor: £1,500-£3,000 per adjoining owner (common with Haringey terraces)
- Building Control: £800-£2,000 depending on project scale
- Pre-application advice (Haringey): £103-£852 depending on service level
Planning Tips for Haringey Extensions
- Verify your conservation area and Article 4 status first. With 28 conservation areas in the borough, there is a high chance your property is affected. Use Haringey's Article 4 directions page or our free property checker to confirm before investing in any design work.
- Don't confuse the two kinds of Article 4 direction. Haringey's conservation-area Article 4 directions (Noel Park, Peabody Cottages, Rookfield Estate, Tower Gardens) affect external alterations like windows and doors. The separate HMO Article 4 direction, covering 14 wards concentrated in the east of the borough, only affects converting a house into a small HMO. A property can be caught by one, both, or neither.
- Highgate properties: check your borough. The Highgate Conservation Area straddles Haringey and Camden. If your property falls within Camden's boundary, your planning application goes to Camden Council, not Haringey. The design expectations are similar but the officer teams, policies, and pre-application services differ.
- Use pre-application advice in sensitive locations. For Crouch End, Muswell Hill, Highgate, and the four conservation areas with their own Article 4 direction, a £312-£498 pre-application advice service is well worth the cost. Officers will indicate likely approval, flag any concerns about materials or scale, and reduce the risk of a refusal that delays your project by months.
- Allow time for party wall notices. The majority of Victorian and Edwardian terraces in Haringey have shared party walls. You must serve notice on adjoining owners at least two months before starting structural work. If neighbours appoint their own surveyor, the award process can take 2-4 months. Build this into your programme from the start.
- Check for trees before any groundworks. Haringey has significant tree coverage, particularly in Highgate, Muswell Hill, and the grounds around Alexandra Palace. TPOs are common and trees within a conservation area are automatically protected. Any groundworks that might affect tree roots - including foundation excavation - require checking against the council's TPO register and, if necessary, an arboricultural impact assessment.
Haringey has 28 conservation areas, covering large parts of Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green. Four of them (Noel Park, Peabody Cottages, Rookfield Estate, Tower Gardens) carry their own Article 4 direction on external alterations. Separately, a partial Article 4 direction across 14 wards in the east of the borough, in force since 30 November 2013, removes permitted development rights for converting a house into a small HMO. A single-storey rear extension costs £58,000-£90,000 all-in inc VAT. A householder planning application costs £548; standard applications take 8 weeks.
Frequently Asked Questions
Do I need planning permission for an extension in Haringey?
It depends on your location and the type of extension. Haringey has 28 conservation areas, including Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green, where conservation area status alone already restricts some permitted development rights. Four conservation areas (Noel Park, Peabody Cottages, Rookfield Estate, Tower Gardens) carry an additional Article 4 direction removing further rights. Outside conservation areas, in parts of Tottenham and Wood Green, standard permitted development rights may apply for small rear extensions. Always verify your specific address before assuming.
How many conservation areas does Haringey have?
Haringey has 28 designated conservation areas, confirmed on the council's own definitive list and in the supporting text to Policy DM9 of the Development Management DPD. The oldest is Highgate (1967) and the most recent is Vallance Road in Tottenham (2008). Five of the 28 (North Tottenham, Scotland Green, Bruce Grove, Tottenham Green, and Seven Sisters/Page Green) together form the Tottenham High Road Historic Corridor.
Does Haringey have an Article 4 direction for HMOs?
Yes, but it is partial rather than borough-wide. Haringey's HMO Article 4 direction has been in force since 30 November 2013 and covers 14 wards concentrated in the east and centre of the borough: Bounds Green, Bruce Castle, Harringay, Hermitage and Gardens, Northumberland Park, Noel Park, St Ann's, Seven Sisters, South Tottenham, Tottenham Central, Tottenham Hale, West Green, White Hart Lane, and Woodside. It removes permitted development rights for converting a house (C3) into a small HMO (C4, three to six occupants). It does not affect standard family extensions and is separate from the Article 4 directions covering specific conservation areas.
Which Haringey conservation areas have their own Article 4 direction?
Four of Haringey's 28 conservation areas carry their own Article 4 direction removing further permitted development rights, such as alterations to windows and doors: Noel Park, Peabody Cottages, Rookfield Estate, and Tower Gardens. Crouch End, Muswell Hill, Highgate, and Stroud Green do not have their own additional Article 4 direction, though the general conservation area restrictions on cladding and roof alterations, plus Policy DM9's design tests, still apply.
Is my Highgate property in Haringey or Camden?
The Highgate Conservation Area straddles both Haringey and Camden. The boundary runs through the conservation area, and some streets fall within Camden's jurisdiction rather than Haringey's. Your planning application must go to the correct council; submitting to the wrong one will cause delays. Check your address against each council's planning map to confirm which borough covers your property.
How much does a rear extension cost in Haringey in 2026?
A standard single-storey rear extension (3m x 5m, 15m²) in Haringey costs an estimated £58,000-£90,000 all-in inc VAT, derived from our London extension costs guide by applying Haringey's position between the Inner London differential (west of the borough) and the Outer London baseline (Tottenham and Wood Green). Add 5-10% for work in any of the borough's 28 conservation areas. Design and professional fees add a further £8,000-£20,000 on top of construction costs.
How much does pre-application advice cost in Haringey?
Haringey charges £103 for general advice, £312 for express written planning advice without a meeting, £498 for standard advice with a meeting, and £852 for properties with a basement. An out-of-office visit adds £240 to the relevant service fee. All fees include VAT. Pre-application advice is strongly recommended for extensions in Crouch End, Muswell Hill, Highgate, and the four conservation areas with their own Article 4 direction.
How long does planning permission take in Haringey?
Standard householder planning applications in Haringey are decided within 8 weeks of validation. Haringey also offers a fast-track service for householder and lawful development certificate applications, which can reduce this period for straightforward cases. Pre-application advice helps reduce the risk of delays from requests for further information or a refusal.
What are the planning application fees in Haringey in 2026?
A householder planning application costs £548, the national fee following the 2026 CPI-linked increase. A lawful development certificate, which confirms that proposed or completed work falls within permitted development, costs £274. Listed building consent applications are fee-exempt.
What is Haringey's new Local Plan and when will it be adopted?
Haringey is preparing a new Local Plan to replace its 2013/2017 Strategic Policies and Development Management DPD. Under the council's Local Development Scheme, approved by Cabinet in March 2025, a Regulation 19 Proposed Submission consultation ran in May and June 2026, with submission to the Planning Inspectorate and examination timetabled for July to November 2026, and adoption targeted for February 2027. Until then, the existing adopted policies remain the ones assessed against householder applications.
Summary
For homeowners in Crouch End, Muswell Hill, Highgate, Hornsey, and Stroud Green, the starting point for any extension is the same: check whether your property sits within one of Haringey's 28 conservation areas, and if so, whether it is one of the four that also carries its own Article 4 direction. Both conservation area status and any additional Article 4 direction narrow what can proceed as permitted development and route more schemes through Policy DM9 and Policy DM12.
In Tottenham and Wood Green, standard permitted development rights apply more often, but the borough's partial HMO Article 4 direction is concentrated in exactly this part of the borough. If your project involves creating a small HMO rather than extending a family home, check whether your ward is one of the 14 covered before assuming permitted development applies.
The first step for any Haringey extension project is confirming your planning status: conservation area, Article 4 (of either kind), listed building, or TPO. That single question determines your route and your realistic timeline.
External Resources
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