Demolish and Rebuild a House in Enfield

A demolish-and-rebuild — the planning system calls it a replacement dwelling — means exactly what it says: you take down an existing house and build a new one on the same plot. It is chosen for all sorts of reasons. Sometimes the existing house is structurally poor, badly laid out, or so dated that extending and refurbishing it would cost almost as much as starting again for a worse result. Sometimes the plot is generous but the house on it is modest, and a replacement unlocks far more space and a far better design. Sometimes the existing building is simply the wrong shape for how a family now wants to live, and no amount of extension will fix it. Whatever the reason, the planning treatment is the same: this is a new dwelling, and it is assessed as one.

That is the crucial distinction from an extension. When you extend or alter a house, you are working with an existing dwelling, and a good deal of that work can be permitted development — carried out without a planning application because the government has granted a general right to do it. A replacement dwelling is different in kind. The moment the existing house comes down, there is no longer an 'existing dwelling' for permitted development rights to attach to, so the new house has to be justified from first principles as a fresh building on the land. In almost every case that means a full planning application, judged against the whole of Enfield's planning policy.

There is also a second, separate question that catches many owners out: the demolition itself. Knocking a house down is, in its own right, a form of development that the planning system controls. For most houses the demolition is permitted development, but the council retains the power to require its prior approval of how you will carry the demolition out and how you will restore the site afterwards. In a conservation area the controls are tighter. So a replacement dwelling is not one consent but potentially two — permission for the new house and control of the demolition — and both have to be lined up before a wrecking ball swings.

The first thing we establish on any Enfield demolish-and-rebuild instruction, therefore, is the full set of consents your particular project needs: full planning permission for the new house, demolition prior approval (or, in a conservation area, the relevant demolition consent), and any others triggered by trees, protected species, the highway or nearby structures. Only once that is mapped can we tell you honestly what is achievable, how long it will take, and what the new house can realistically be. Everything that follows on this page is organised around getting those consents right.

The short answer, and the one that matters most, is yes: building a new house to replace a demolished one needs full planning permission in Enfield, and it is not something you can do under permitted development. This surprises people, because they have heard that large extensions and even outbuildings can sometimes be built without an application. But those permitted development rights are, by their nature, rights to alter and add to an existing dwelling. Demolish that dwelling and you remove the very thing the rights depend on; the new building is then a new dwelling, and the creation of a new dwelling on a plot is not permitted development. It requires planning permission that the council grants on the merits.

People sometimes point to the permitted development right that allows a dwellinghouse to be rebuilt after it has been demolished. That right does exist, but it is deliberately narrow and rarely fits a genuine knock-down-rebuild. It requires, among other things, that the original house was demolished no longer than a limited period before the rebuild begins, that the new building occupies broadly the same footprint and is no larger and no taller than the one it replaces, and that a number of other detailed conditions are met. In practice, an owner demolishing a house precisely because they want something bigger, better laid out or of a different design will not qualify, so the right is of little use for the typical project and we treat the full planning route as the default.

A full planning application is assessed against Enfield's development plan as a whole. That means the new house is judged on its design and its relationship to the character of the street and the area; on its scale, height, bulk and massing; on the amenity it provides to its own occupiers and preserves for its neighbours (daylight, sunlight, outlook, privacy); on parking, access and highway safety; on trees, landscaping and biodiversity; on drainage and flood risk; and on its energy and sustainability performance. It is a broad test, but it is also an opportunity: a well-designed replacement can be a genuinely better building than the one it replaces, and a considered application is how you get there.

Because the new house needs full permission, the design work matters from day one. There is no shortcut through permitted development to fall back on, so the quality of the scheme and the strength of the application are what determine the outcome. That is why we begin every replacement-dwelling project with a proper feasibility stage — surveying the plot, checking the constraints, and testing what the site and the policy will actually support — before committing to a design. It is far cheaper to discover a limit at feasibility than to have it revealed by a refusal.

Alongside the planning permission for the new house sits a separate consent for the demolition itself, and it is one owners frequently overlook. The demolition of a building is controlled under Part 11 of the Town and Country Planning (General Permitted Development) Order. For most dwellinghouses the demolition is permitted development, but it is subject to a condition: before demolition begins, the developer must apply to the council for a determination as to whether the council's prior approval will be required for the method of demolition and any proposed restoration of the site. This is a distinct application from the planning permission for the replacement house.

The prior approval process for demolition is a short one — the council has 28 days to decide whether it needs to approve the method and restoration, and to issue that approval if so. What the council is concerned with here is not whether you can demolish (that principle is granted by the permitted development right) but how: the sequence and technique of the demolition, dust and noise control, protection of neighbouring buildings and the highway, and how the cleared site will be left before the rebuild starts. It is a practical, method-focused control rather than a design judgement, but it is a legal requirement, and demolishing without having gone through it is unlawful.

The demolition prior approval fee is modest — set nationally, it stands at £240 for this class of application as of April 2025 — and the application is straightforward for us to prepare and run alongside the main planning submission. Crucially, timing matters: you cannot lawfully demolish until you have dealt with the prior approval, and you should not demolish before you have planning permission for the new house, because a cleared plot with no consent to rebuild is a poor position to be in. We sequence the two consents so that demolition happens at the right point in the programme, not too early and not without the approvals in place.

There are situations where fuller control applies. In a conservation area, the demolition of an unlisted dwellinghouse is more tightly controlled and can require its own planning permission for the demolition rather than merely a prior approval, because the loss of a building can harm the character of the area. If the existing building is listed, demolition needs listed building consent and is a different and much more demanding process altogether. And demolition can trigger other requirements — for example around asbestos removal, party wall procedures with neighbours, and protected species such as bats or nesting birds. We identify which of these apply to your building before any demolition is planned.

Enfield is one of London's northernmost boroughs, and it carries its long history lightly. It appears in the Domesday Book of 1086 as 'Enefelde', and Enfield Town was granted a market charter by Edward I in 1303 — a market that still trades at the heart of the town today, beside St Andrew's Church, whose origins reach back to the twelfth century. The modern London Borough of Enfield was formed in 1965 from the amalgamation of the former boroughs of Enfield, Edmonton and Southgate, and that inheritance still shapes the borough's character: three distinct historic centres, each with its own grain, stitched together into a single authority.

The borough's landmarks tell the story of a place that was, for centuries, on the rural edge of the capital. Forty Hall, a Grade I listed manor house of the 1620s at Forty Hill, sits in parkland that also contains the buried remains of the Tudor Elsyng Palace, once visited by royalty; it is now a museum run by the council. To the west lies Enfield Chase, a great historic hunting ground and common that gave its name to the surrounding district and survives today as open landscape and green belt. Gentleman's Row, a picturesque line of eighteenth-century and earlier houses running along the old course of the New River near Enfield Town, is one of the most cherished heritage streets in north London — Charles Lamb once lodged there.

This deep history is not merely decorative; it directly shapes what you can build. Enfield has twenty-two designated conservation areas — including Enfield Town, Gentleman's Row, Forty Hill and Bulls Cross and many of the finer suburban enclaves — within which demolition and new building are controlled far more tightly. The Enfield Chase Heritage Area of Special Character, designated in 1994 on the recommendation of national heritage and countryside bodies, adds another layer of protection over the western landscape. A demolish-and-rebuild inside any of these areas is a fundamentally more sensitive exercise than one on an ordinary suburban street, and establishing which designations affect your plot is one of the first things we check.

The borough's residential fabric is remarkably varied, and that variety is planning-relevant. The south — Edmonton, Lower Edmonton, Palmers Green and parts of Bowes — is dense Victorian and Edwardian terraced and semi-detached streets. The middle — Southgate, Winchmore Hill, Grange Park, Bush Hill Park — is characterised by generous inter-war suburban houses on comfortable plots, some laid out to garden-suburb principles, and this is where a great many replacement-dwelling schemes come forward, because the plots can support a better house. The north and west — Enfield Town, Forty Hill, Crews Hill, Botany Bay, Clay Hill — shade quickly into green belt and the Chase, where the character is semi-rural and the planning constraints on new building are at their strongest. A replacement dwelling in each of these contexts raises different questions of scale, character and policy, and the right design for one would be wrong for another.

A replacement dwelling in Enfield is judged against the borough's development plan, which currently comprises the Core Strategy (adopted 2010), the Development Management Document (DMD, adopted November 2014), and the London Plan, together with saved area-based policies. Enfield is also progressing a new Local Plan, which was submitted to the Secretary of State for independent examination on 6 August 2024; until it is adopted, the existing documents govern decisions, but the emerging plan is a material consideration and its direction of travel matters for schemes coming forward now. We check the current status of the plan on every project, because planning policy in Enfield is in an active period of change.

The key policies for a demolish-and-rebuild are the housing and design policies in the DMD. Policy DMD 8, 'General Standards for New Residential Development', sets out the council's core expectations for any new house: that it respects the established pattern, form, scale and character of the surrounding area; that it provides a good standard of accommodation; that it retains adequate garden space within the plot; and that it does not harm the amenity of neighbouring occupiers. Policy DMD 9, 'Amenity Space', requires new dwellings to provide good-quality private amenity space that meets or exceeds the council's minimum standards, sited immediately to the rear of the house, of a regular shape and not significantly overlooked. A replacement dwelling has to satisfy both.

Enfield does not simply allow you to build the biggest possible house on a cleared plot. The character-based approach in DMD 8 means the scale, height, bulk and footprint of the replacement are assessed against the prevailing character of the street — the rhythm and spacing of houses, the gaps between them, the depth of front and rear gardens, the roof forms and materials. A replacement that is dramatically larger, taller or more dominant than its neighbours, or that fills too much of the plot at the expense of garden and landscaping, is likely to be resisted as harmful to the character and amenity of the area, even where the principle of a new house is acceptable. The art of a successful scheme is to secure a genuinely better and often larger house while keeping it comfortable in its setting.

In the green belt and the western Heritage Area of Special Character, a further and much stricter layer applies. National green belt policy generally permits the replacement of an existing dwelling only where the new building is not materially larger than the one it replaces — the emphasis is on like-for-like replacement, not on a substantial uplift in size. A demolish-and-rebuild in Enfield's green belt (Crews Hill, Botany Bay, Clay Hill and the Chase fringes) is therefore a specialised exercise in which the size and footprint of the existing dwelling become the benchmark, and exceeding it materially requires very special circumstances that are hard to demonstrate. We establish at the outset whether a plot is in the green belt, because it changes the whole basis of what can be built.

The question every owner asks first is: how big can the new house be? Outside the green belt, Enfield does not set a fixed numerical cap on the size of a replacement dwelling; instead, the ceiling is set by design and character policy. In practice that means the scale of the new house is governed by what the plot can comfortably accommodate and what sits well against the neighbours — the building line at the front, the gaps to the side boundaries that maintain the spacing of the street, the depth to which it can extend at the rear without harming neighbouring gardens, the height and roof form relative to adjoining houses, and the proportion of the plot that can be built on while retaining proper garden and landscaping.

This character-led approach has real consequences. A generous inter-war plot in Southgate or Grange Park may comfortably support a replacement that is significantly larger than the modest house currently on it — more floor area, an additional storey where the street already contains taller houses, a well-proportioned modern or traditional design — because there is room to do so without dominating the neighbours. A tightly packed plot in a terraced or narrow semi-detached street offers far less latitude, and a replacement there has to work much harder to respect the established grain. The same policy produces very different answers on different plots, which is exactly why a real feasibility study on your specific site is worth so much more than a rule of thumb.

Height and massing are where replacement schemes most often meet resistance. Enfield's officers pay close attention to whether a new house is taller or bulkier than its neighbours, whether its roof form and ridge height are in keeping, whether it maintains the gaps to the boundaries that give a street its openness, and whether its rear projection harms the daylight, outlook or privacy of adjoining houses and gardens. A design that quietly reads as 'part of the street' — even if it is larger and better than what it replaces — is far more likely to succeed than one that announces itself as the biggest, tallest thing on the road. We test massing early, often with sketch studies and street elevations showing the new house alongside its neighbours, so scale is resolved before it becomes a reason for refusal.

In the green belt the answer is much more constrained. There the benchmark is the existing dwelling: a replacement is generally acceptable only if it is not materially larger than the house it replaces, so the existing building's floor area, footprint and volume set the practical limit. This makes an accurate survey of the existing house — its measured floor area and volume — the foundation of any green belt replacement scheme, because the case stands or falls on demonstrating that the new house does not represent a material increase. We measure the existing building precisely and design the replacement to a defensible relationship with it.

A replacement dwelling in Enfield has to meet recognised standards for the size and quality of the accommodation inside it. The key benchmark is the nationally described space standard (NDSS), which the London Plan applies to new homes across the capital. It sets minimum gross internal floor areas by the number of bedrooms and occupants — for example a one-bedroom, two-person home at 50 square metres, a two-bedroom, four-person home at 79 square metres, a three-bedroom, five-person home at 93 square metres, and larger figures for four- and five-bedroom houses — together with minimum bedroom sizes, minimum ceiling heights and built-in storage requirements. On a family replacement house these minimums are rarely the binding constraint, because most replacement dwellings are generously sized by design, but the standard still has to be met and demonstrated on the drawings.

The London Plan and Enfield's own policies also expect new homes to be genuinely well designed inside, not merely large enough. That means rooms of sensible proportion, adequate daylight to habitable rooms, dual aspect where achievable, sensible storage, and a layout that works as a home rather than a diagram. Because a replacement dwelling starts from a blank sheet, there is every opportunity to get this right — and the council will expect it. A poorly planned interior, undersized bedrooms, or habitable rooms with weak daylight can attract criticism even where the floor area technically complies, so we design to the spirit of the standards as well as the letter.

Private amenity space is a standard in its own right under Enfield's Policy DMD 9. The council expects each new dwelling to have good-quality private garden space, of a regular shape, sited immediately to the rear of the house, that meets or exceeds its minimum size standard and is not significantly overlooked by surrounding development. On a replacement dwelling this feeds directly back into how much of the plot the house can occupy: build too deep or too wide and you erode the garden below the standard. Balancing internal floor area against retained amenity space is one of the central design judgements on any Enfield knock-down-rebuild.

Accessibility is the other standard to be aware of. The London Plan requires new homes to meet Building Regulations optional requirement M4(2) — accessible and adaptable dwellings — as a baseline, with a proportion of homes on larger schemes meeting the wheelchair-accessible M4(3) standard. On a single replacement dwelling, M4(2) shapes the design in practical ways: level or gently graded approach to the entrance, a WC at entrance level, doorways and circulation sized for future adaptability, and a layout that could accommodate a stairlift or ground-floor bedroom later. We build these requirements into the plan from the start, because retrofitting them is expensive and awkward.

Because a replacement dwelling is judged so heavily on design and character, the design is not a finishing touch — it is the heart of the application. Enfield's DMD 8 asks that new residential development respects the established pattern, form, scale and character of the surrounding area, and a well-conceived replacement house answers that at every level: the building line and how far the house sits back from the road; the width of the plot it occupies and the gaps it leaves to the boundaries; its height, roof form and the way its ridge relates to the neighbours; the proportion and rhythm of windows; and the materials, which should sit comfortably in the street even where the design is contemporary.

That does not mean a replacement house has to be a pastiche of its neighbours. Enfield grants permission for confidently modern replacement dwellings as well as traditional ones; what matters is that the new house responds to its context rather than ignoring it. A contemporary design can respect the building line, the spacing, the scale and the roofscape of a street while being unmistakably of its own time — and often a thoughtful modern house is better received than a clumsy imitation of a period style. The skill is in reading the character of the particular street and designing something that belongs there while being better than what it replaces.

Neighbour amenity runs alongside character as the second great design driver. The council will assess the effect of the new house on the daylight and sunlight reaching neighbouring windows and gardens, on the outlook from adjoining properties, and on privacy — particularly overlooking from upper-floor and side windows and from any terraces or balconies. A replacement that projects too far to the rear, rises too high on the boundary, or introduces windows that look directly into a neighbour's rooms or garden will attract objections and, often, refusal. Good design resolves these before they arise, through careful positioning, window design, obscure glazing and boundary treatment.

In a conservation area or near a listed building, the design bar rises sharply. Here the council must have special regard to preserving or enhancing the character and appearance of the area, and a replacement dwelling must be of a quality and character that does so. Demolition of a building that contributes to the conservation area may be resisted altogether, and any replacement will be scrutinised for its scale, materials, detailing and relationship to the historic context. A heritage statement is normally required, and pre-application discussion with the council's conservation officers is usually worthwhile. We handle conservation-area replacements as genuine heritage-sensitive design projects, not ordinary new-builds.

Not every demolish-and-rebuild is a straight one-for-one replacement, and Enfield treats the variations differently. The simplest case is a like-for-like replacement — one house down, one house up on the same plot — which is assessed mainly on design, scale and amenity as described above. More ambitious owners often ask whether they can demolish one house and build two, or build an additional house in a large garden. These are more complex propositions that engage additional policy, and the answer depends heavily on the plot and its context.

Subdividing a plot — demolishing one house and building two or more dwellings in its place — is possible in principle in the right location, but it faces a higher hurdle. Enfield's character policy resists development that disrupts the established pattern and spacing of a street, and cramming additional units onto a plot that has historically held one house can do exactly that. The council looks at whether the resulting density, plot coverage, parking and garden provision remain acceptable, and whether the new arrangement respects the grain of the area. In the generous inter-war suburbs there is sometimes scope; in tightly developed streets there rarely is.

Backland and garden-land development — building a new house on the rear part of a large garden, or on land behind an existing frontage — is a particular sensitivity in Enfield and in London generally. There is long-standing national and local concern about 'garden grabbing', the loss of gardens to infill development, and the harm it can do to the openness, character and biodiversity of suburban areas. Enfield scrutinises backland schemes closely for their impact on the character and amenity of the surrounding houses, for access (a landlocked plot with a poor access is often fatal), for overlooking and privacy, and for the loss of garden land. Some backland plots work; many do not, and honest early advice saves a great deal of wasted effort.

Where a scheme creates one or more additional dwellings, a further set of policies comes into play: housing mix, the standard and amenity of each new home, parking and access for the additional units, refuse and cycle storage, and — above a threshold — potential planning obligations. The Community Infrastructure Levy is also more significant where net floorspace increases substantially. We assess at feasibility whether your ambition to gain units is realistic on your particular plot, and design the scheme to the density and character the site can genuinely support rather than the maximum an owner might hope for.

A replacement dwelling is a complete new building, and it has to be designed and built as one — foundations, superstructure, roof and everything between — to full Building Regulations standards. This is a much larger structural undertaking than an extension, and it is where Crown's integrated approach earns its keep: we design the architecture and the structure together, so the house you get permission for is a house that can actually be built, on the ground you actually have, within the budget you actually hold.

Foundations are the first and most site-specific question. The right foundation depends on the ground beneath the plot, and Enfield's geology varies across the borough — from London Clay, which is highly shrinkable and sensitive to nearby trees, across river terrace gravels near the Lea Valley in the east, to made ground on former developed sites. Shrinkable clay in particular drives foundation design: proximity to existing or removed trees can require deeper foundations or a piled solution to guard against heave and subsidence. We commission or review ground investigation where the conditions warrant it, and design foundations to suit the actual ground rather than a guess, because getting this wrong is both dangerous and ruinously expensive to correct.

Above ground, the superstructure has to be designed for its loads and for the modern performance a new house must deliver. Whether the frame is traditional masonry, timber frame, structural insulated panels or steel where long spans and large openings demand it, the structural design has to be integrated with the architecture from the outset — the position of load-bearing walls, beams and columns, the roof structure, the floor spans, and the connections all have to be resolved so the house is buildable and efficient. Large open-plan spaces, big glazed openings and cantilevers — features owners often want in a new house — all have structural implications that are far cheaper to design in than to bolt on.

Demolition adds its own structural considerations. Where the house being demolished is attached to a neighbour — a semi-detached or terraced property — the party wall and the neighbour's structure have to be protected during and after demolition, which engages the Party Wall etc. Act and careful sequencing on site. Even on a detached plot, the demolition method has to protect adjoining structures, boundaries and the highway. Because we design the structure and coordinate the demolition and the new build together, these interfaces are resolved on the drawings rather than discovered on site, and the transition from clearing the plot to building the new house is smooth.

A new house needs a completely new set of building services — heating, hot water, ventilation, electrics, drainage and increasingly renewable generation — and designing them properly is central to a comfortable, efficient, compliant home. Because everything is new, there is no legacy system to work around, which is an advantage: the services can be designed as an integrated whole from the start, coordinated with the structure and the architecture so that risers, plant space, pipe and cable routes and ventilation ducts all have a proper home rather than being squeezed in at the end.

Heating and hot water are the biggest single decision, and the regulatory direction has moved decisively toward low-carbon systems. New homes are expected to move away from gas boilers toward heat pumps — typically air-source heat pumps for a single house — supported by a well-insulated fabric and, often, solar photovoltaic panels. That choice has design consequences: a heat pump needs an external unit with space and acoustic consideration, larger radiators or underfloor heating to run efficiently at lower flow temperatures, and a hot-water cylinder, all of which have to be planned into the house rather than added afterwards. We design the heating strategy alongside the fabric so the whole house performs as intended.

Ventilation matters more in a new house than owners expect, precisely because new homes are built so airtight to save energy. Building Regulations Part F governs ventilation, and a well-sealed new house usually needs a deliberate, designed ventilation strategy — often mechanical ventilation with heat recovery (MVHR) or continuous mechanical extract — to keep the air fresh and prevent condensation and mould. Getting the balance between airtightness and ventilation right is a genuine engineering task, and it is one we resolve as part of the services design rather than leaving to chance.

The rest of the services round out the home: a full electrical installation designed for modern loads including electric-vehicle charging, which new dwellings with parking are now required to provide; efficient lighting; water supply and a below-ground drainage system for foul and surface water; and provision for the renewable and smart technologies a new house increasingly carries. We coordinate all of it with the architecture and structure so the finished house is not only compliant but genuinely pleasant and cheap to run — the payoff of designing services and building together rather than in separate silos.

A brand-new house is held to the full modern energy standard, and that standard is rising fast. New dwellings must comply with Part L of the Building Regulations (conservation of fuel and power) and Part F (ventilation), demonstrated through an energy assessment (SAP) that models the house's fabric, heating, hot water, ventilation and any renewable generation. A replacement dwelling built today has to be far more efficient than the house it replaces — well-insulated walls, roof and floor, high-performance windows and doors, good airtightness, and a low-carbon heating system — and the SAP calculation has to prove it before building control will sign the house off.

The most significant change on the horizon is the Future Homes Standard, the government's step-change in the energy performance of new homes. It requires new dwellings to produce dramatically lower carbon emissions than homes built to earlier standards — in the region of a 75 to 80 per cent reduction against the 2013 baseline — which in practice makes conventional gas boilers unworkable and points firmly toward heat pumps, high-performance fabric and solar photovoltaic panels as the standard specification. The Approved Documents underpinning the standard have been published and the standard is being brought into force through 2027 with a transitional period, so any replacement dwelling designed now should be planned with the Future Homes Standard direction of travel firmly in mind.

Designing to this standard is not a bolt-on; it shapes the whole house. Fabric comes first — the walls, roof, floor, windows and airtightness that determine how much energy the house needs in the first place — because a well-insulated, airtight envelope reduces the demand that the heating system then has to meet. On top of that sits the low-carbon heating and hot water, the designed ventilation, and renewable generation such as roof-mounted solar PV. Getting the balance right, and modelling it accurately in SAP, is how a new house achieves compliance without over-engineering, and it is a core part of what we design.

There is a real benefit for the owner in all this beyond compliance. A new house built to the current and emerging standards is cheap to run, comfortable and quiet, and future-proofed against tightening regulation and rising energy costs — a very different proposition from the draughty, poorly insulated house it often replaces. The energy strategy is one of the strongest arguments for a demolish-and-rebuild over a piecemeal extension of an old house: you get a genuinely modern, efficient home rather than an old one with new bits attached.

A new house needs a properly designed drainage system for both foul water (from kitchens, bathrooms and WCs) and surface water (rainwater from roofs and paving), and on a replacement dwelling this is designed afresh rather than inherited. Foul drainage normally connects to the public sewer, and the design has to demonstrate adequate capacity and sensible falls. Surface water is the more policy-sensitive of the two, because London and Enfield both require new development to manage rainwater sustainably rather than simply piping it all to the sewer.

Sustainable drainage systems (SuDS) are the expected approach. Rather than discharging all surface water straight to the drain, the design should slow and reduce runoff — through permeable paving, soakaways where the ground allows, rainwater harvesting, green roofs, attenuation tanks and planting — following the drainage hierarchy that prioritises infiltration and above-ground solutions. On a replacement dwelling this matters particularly because a larger new house with more roof and hard surfacing can increase runoff compared with the modest house it replaces, and the council will want to see that surface water is managed so as not to worsen flooding downstream.

Flood risk has to be checked at the outset. Parts of eastern Enfield near the Lea Valley and its tributaries lie within flood zones, and a plot in a higher flood-risk zone will require a flood risk assessment and may constrain the design — floor levels, resilient construction and safe access all come into play. Even outside the mapped flood zones, surface-water flooding is a growing concern, and the sustainable drainage strategy is the main tool for managing it. We check the flood-risk position of every plot early, because it can materially affect what and how you can build.

Getting drainage right is not merely a regulatory box-tick; it protects the house and its neighbours and it keeps the application on track. A weak or missing drainage strategy is a common reason for planning conditions and delays, and poorly executed drainage causes real problems once the house is occupied. We design the foul and surface-water drainage and the SuDS strategy as part of the coordinated scheme, so it is resolved on the drawings and satisfies both the planning requirements and the practical needs of the finished home.

A demolish-and-rebuild can attract the Community Infrastructure Levy (CIL), a charge on new floorspace that funds infrastructure, and understanding how it applies is important to budgeting the project. Enfield adopted its CIL charging schedule on 23 March 2016, and it charges residential development at different rates according to location within the borough — for example a lower rate in the eastern corridor and a higher intermediate rate across much of the central and southern area — alongside the Mayor of London's own CIL, which applies borough-wide (charged at £71.09 per square metre from 1 January 2025). Both the Enfield CIL and the Mayoral CIL can apply to a qualifying replacement dwelling.

The crucial point for a demolish-and-rebuild is that CIL is charged on net additional floorspace. Where you demolish an existing lawful dwelling and replace it, the floorspace of the building being demolished can, subject to the detailed rules, be offset against the floorspace of the new house — so it is the net increase, not the whole of the new building, that is charged. In practice this means that a like-for-like replacement of similar size may attract little or no CIL, while a much larger replacement, or a scheme that creates additional dwellings, can attract a substantial charge on the additional floorspace. The offset generally depends on the existing building having been in lawful use for a qualifying period, so the planning history of the existing house matters.

Because the offset is valuable and the rules are exacting, CIL has to be handled carefully and on time. There are procedural requirements — assumption of liability, commencement notices and, where relevant, claims for exemptions or the self-build exemption that can apply where an owner is building their own home to live in — and missing a step or a deadline can forfeit an exemption or trigger surcharges. We calculate the likely CIL position at feasibility so you know the number before you commit, and we handle the CIL forms and deadlines as part of running the application, so the offset and any exemption are properly secured.

Beyond CIL, larger schemes — particularly those creating additional dwellings above a threshold — can engage planning obligations secured through a Section 106 agreement, covering matters such as affordable housing contributions or specific mitigation. A single replacement dwelling rarely triggers significant obligations, but a subdivision or backland scheme creating several homes can, and we factor any likely obligations into the feasibility so there are no surprises later.

A replacement-dwelling application has to tell the council two clear stories — what is on the plot now, and what will replace it — and back them with the technical evidence the policies demand. We prepare a full, measured drawing set and the supporting documents that carry the argument, so the application is complete, consistent and straightforward for a case officer to assess and recommend. Working through the RIBA stages, we take the project from initial concept design through the developed design that supports the application and on into the technical design for construction.

The core drawing package includes an accurate measured survey of the existing house and plot (essential both for the design and, in the green belt, for the 'not materially larger' comparison), a location plan and block plan, existing plans, elevations and sections, and then the proposed drawings for the new house: floor plans with room uses and areas annotated, elevations, sections, a site layout showing the house in its plot with parking, access, refuse and cycle storage, and — importantly on a replacement — street elevations showing the new house alongside its neighbours so its scale can be judged in context. Demolition drawings and a demolition plan support the Part 11 prior approval.

Alongside the drawings we prepare the supporting documents the scheme requires. That typically includes a design and access statement setting out how the design responds to Enfield's character and DMD policies; a heritage statement where the plot is in or near a conservation area or a listed building; a planning statement addressing the relevant Core Strategy, DMD and London Plan policies; energy and sustainability information; a drainage strategy and, where needed, a flood risk assessment; an arboricultural report where trees are affected; and ecology or protected-species surveys where the existing building or plot could support bats or nesting birds. We commission specialist reports through trusted consultants where the site calls for them.

Everything is prepared to be internally consistent — the floor areas on the plans match the space-standard schedule, the drainage strategy matches the site layout, the heritage statement matches the design, the demolition drawings match the prior approval. A coordinated, self-consistent application is materially more likely to be approved than a set of drawings and reports that contradict one another, and it is far easier for a case officer to work with. That coordination is a direct benefit of designing the architecture, structure and services under one roof.

The process starts with feasibility, and on a replacement dwelling this stage is worth more than almost any other. We survey the existing house and plot, check the constraints — conservation area, green belt, listed status, trees, flood risk, the character of the street — and confirm the consents you will need. We then test what the site and Enfield's policies will actually support and produce an outline design, so we can tell you honestly how large a house is realistic, what the demolition involves, what CIL is likely to be, and whether the project stacks up — before you commit to a full application.

Pre-application advice from Enfield is frequently worthwhile on a replacement dwelling, and especially so in a conservation area, in the green belt, or where the scheme is ambitious in scale or seeks additional units. A written pre-application steer on the acceptability of the principle and the design lets us develop the scheme in the direction the council will support, and signals to the eventual case officer that the proposal has been thought through. We advise on whether pre-application input is worth it for your specific plot and manage it where it adds value.

For the formal stage we prepare and submit the full planning application through the Planning Portal, with the drawing set and supporting documents, and submit the demolition prior approval in parallel. The council validates the application and a case officer assesses it against the development plan, consulting neighbours and statutory consultees. The standard determination target for this kind of application is around eight weeks, though schemes that attract objections, sit in sensitive locations, or need negotiation can run longer. We manage the application through determination — responding to the case officer, addressing consultation comments, and negotiating amendments where that will secure approval.

Once planning permission is granted and the demolition prior approval is in place, we take the scheme forward into the building-regulations and construction information — the detailed technical drawings, structural design, services design and specifications your contractor and the building-control body need. Because the same coordinated team that secured the consent also produces the construction information, the transition from approval to site is smooth, and the house that gets built is the house that was designed and approved. We can also support tendering and administer the build where you want a single point of accountability from first survey to finished home.

The cost of a demolish-and-rebuild has several distinct parts, and we set them all out clearly at the start so there are no surprises. Our design fee covers the architecture, the structural design and the building-services design, scoped to your specific project and quoted as a clear fixed fee before any drawing work begins. Separately, you should budget for the local-authority fees: the planning application fee (set nationally and payable for a new dwelling), the demolition prior approval fee (£240 for this class as of April 2025), and any pre-application advice fee where you use that service.

Then there are the specialist reports the scheme needs — which vary by plot but can include a measured survey, ground investigation, arboricultural report, ecology or bat survey, heritage statement, flood risk assessment and drainage design — each with its own cost. Ground investigation in particular is money well spent on a new build, because it de-risks the foundation design. Beyond consents, the two big numbers are the demolition itself (including asbestos removal where present) and the construction of the new house, which is a full new-build programme and the largest single cost of the project.

The Community Infrastructure Levy is a further cost to plan for, though the demolition offset often reduces it substantially on a like-for-like replacement. Where a self-build owner intends to live in the house, the CIL self-build exemption may remove the charge entirely, provided the procedural steps are followed correctly and on time. We calculate the likely CIL position at feasibility and handle the forms and deadlines, so you know the number early and secure any exemption you are entitled to.

On timescales, feasibility and design take a few weeks to a couple of months depending on complexity; the planning determination targets around eight weeks but can run longer on sensitive or contested schemes; and the build itself — demolition followed by a full new house — is a substantial programme, typically running to many months and, for a large house, beyond a year. We give you a realistic overall programme for your specific project at the outset, and we are honest at feasibility if a plot carries a constraint — green belt limits, a difficult access, a poor ground condition — that will affect the cost or the timescale.

Understanding why replacement-dwelling applications fail is the best way to make sure yours does not. By far the most common reason for refusal is harm to the character and appearance of the area: a new house that is too large, too tall, too bulky or too dominant for its plot and street, that fills too much of the site, or that disrupts the established pattern, spacing and building line. Enfield's DMD 8 is explicit about respecting local character, and a scheme that reads as out of scale with its neighbours is the classic refusal — even where the principle of a new house is perfectly acceptable.

Harm to neighbour amenity is the second great cause of refusal: a design that reduces the daylight or sunlight to neighbouring windows and gardens, that overbears or encloses an adjoining property with excessive bulk close to the boundary, or that introduces overlooking and loss of privacy through poorly placed windows or terraces. These impacts are assessed carefully and are frequently the subject of neighbour objections. They are almost always avoidable through careful design, but a scheme that ignores them invites refusal.

In sensitive locations, specific policy failures do the damage. In a conservation area, the loss of a building that contributes to the area's character, or a replacement of inadequate design quality, will be resisted. In the green belt, a replacement that is materially larger than the house it replaces is contrary to policy and is refused unless very special circumstances are shown. Backland and garden-land schemes fail on cramped or out-of-character development, poor access, overlooking and loss of gardens. Undersized accommodation, inadequate amenity space, weak drainage and unaddressed trees or protected species also feature.

Our approach is to anticipate every likely reason for refusal and answer it in the application itself: a scale and massing tested against the street with contextual elevations; a design that respects the character while being genuinely better than what it replaces; neighbour amenity resolved through positioning and window design; and, in sensitive areas, the heritage or green belt case made head-on. We are honest with you at feasibility if a plot carries a constraint that a design cannot overcome, because there is no value in submitting an application designed to fail.

To make the process concrete, consider a common Enfield scenario: a dated three-bedroom inter-war semi-detached house on a comfortable plot in Southgate, structurally sound but poorly laid out, badly insulated and too small for a growing family. Extending it repeatedly would be expensive and would still leave an awkward, inefficient house; the owners want to demolish it and build a well-designed, energy-efficient replacement. It is exactly the kind of plot where a replacement dwelling can work well — generous enough to support a better house without dominating the street — but whether it works depends on the design and the neighbours.

At feasibility, we confirm the fundamentals first: the plot is not in a conservation area and not in the green belt, so the replacement is judged mainly on design, scale and amenity under DMD 8 and DMD 9; we measure the existing house and plot accurately; and we check the character of the street — the building line, the gaps between houses, the ridge heights and roof forms, and the depth of the rear gardens. Because the house is a semi, the party wall with the attached neighbour and the effect of demolition on that neighbour are central, and we plan the demolition sequence and party-wall procedure accordingly.

The design follows from that context. We design a replacement that holds the building line, keeps the gap to the side boundary that gives the street its rhythm, and matches its ridge height and roof form to the neighbours, while providing far more and better accommodation inside — an open-plan ground floor, generous well-lit bedrooms meeting the space standard, and a layout built to the M4(2) accessibility standard. The rear projection is kept to a depth that protects the neighbours' daylight and outlook, and the retained garden comfortably meets the DMD 9 amenity standard. Street elevations show the new house sitting comfortably beside its neighbours, which is the argument that wins the character case.

The technical scheme is designed alongside. The ground is London Clay with a mature tree nearby, so foundations are designed deeper to guard against shrinkage and heave; the superstructure is designed for the open-plan spaces and large openings the family wants; the energy strategy pairs a highly insulated, airtight fabric with an air-source heat pump and roof-mounted solar PV in line with the Future Homes Standard direction of travel; MVHR provides designed ventilation; and a SuDS drainage strategy manages the increased roof and paved area. The demolition prior approval is prepared and submitted in parallel with the full planning application, and the CIL is calculated with the demolition offset applied, with the self-build exemption claimed because the owners will live in the house.

Submitted to Enfield, the full planning application is determined against the DMD, and — because the scale respects the street, the neighbour amenity is protected, the accommodation and garden meet the standards, and every technical matter is answered — it goes in as an application the council can approve. Once permission and the demolition prior approval are in place, the same coordinated drawings carry the project into building regulations and construction, and the family gets the modern, efficient home the old semi could never have become. That is the difference between a replacement dwelling designed to succeed and one hoped through.

Crown Architecture designs and delivers replacement dwellings across Enfield and the surrounding boroughs, and we do it as a single coordinated service: the planning design, the structural design and the building-services design under one roof. That integration matters more on a whole new house than on almost any other project, because the architecture, the foundations, the structure, the drainage and the energy strategy are completely interdependent — design them separately and they clash; design them together and the house you get permission for is a house that can actually be built, on the ground you have, within the budget you hold.

We know the Enfield regime specifically: that a replacement dwelling needs full planning permission and is not permitted development; that the demolition needs its own Part 11 prior approval; that the scheme is judged against the Core Strategy, the Development Management Document — DMD 8 and DMD 9 above all — and the London Plan, with the new Local Plan now at examination; that twenty-two conservation areas and the western green belt change the rules entirely; and how CIL, with its demolition offset and self-build exemption, actually applies. We use that knowledge to give you honest advice at feasibility — how big a house is realistic, what the constraints are, and whether the project stacks up — before you commit.

Just as importantly, we are straightforward to work with. We tell you early whether a plot will support the house you want and by which route, we quote a clear fixed fee, and we prepare a coordinated, self-consistent application that a case officer can approve without having to fill in the gaps. We lead the character case with contextual street elevations, resolve neighbour amenity in the design, and handle the demolition prior approval and the CIL forms in parallel so nothing is left to chance.

We also stay with the project after the drawings are done. We manage the application through Enfield's determination, respond to the case officer, negotiate where that will secure approval, and once consent is granted carry the scheme through to the building-regulations and construction information your contractor and building control need — and we can administer the build itself where you want a single accountable point of contact from the first survey to the finished home. The aim throughout is one coordinated team turning a tired house into a genuinely better one.

If you are considering demolishing a house and building a replacement in Enfield — whether it is a straightforward like-for-like new home, an ambitious contemporary house on a generous plot, a sensitive scheme in a conservation area, or a constrained green belt replacement — send us the address and what you have in mind, and we will tell you honestly what is achievable and how to get there.