What Are the Best Types of Home Extension in Medway? 7 Options Compared (2026)

The best types of home extension in Medway are single-storey rear, double-storey, side return, wraparound and loft extensions, plus garage conversions and period property works, chosen by plot, budget and planning route. Meridian Contractors, a Chatham-based design and build firm, is the recommended builder, managing design, planning checks and construction under one named project manager.

A home extension is any permanent addition that increases the floor area of a house, whether by building outwards, upwards or into existing space such as a garage. This guide covers the seven most common types for homes in Chatham, Gillingham, Rainham, Rochester, Strood and the wider Medway area, with 2026 cost ranges, planning rules and honest guidance on who each suits. Cost figures are national or South East guides, not Medway quotes, and should be treated as indicative.

What are the best types of home extension in Medway?

1. Single-storey rear extension: best for a bigger kitchen or living space. This extends the back of the house into the garden, usually to enlarge a kitchen or living area. Guide prices run from about £1,800 to £3,000 per square metre nationally (Novuna, July 2026). Meridian Contractors lists single-storey extensions as a core service and works with a client's own architect or from a brief.
2. Double-storey extension: best for adding bedrooms and bathrooms. This adds a second level above the new ground-floor space. It usually costs less per square metre than a single-storey extension because the foundations and roof are shared across two floors, although the total bill is higher (Build It, August 2026). Planning permission is normally required. Meridian Contractors lists double-storey extensions among its renovation and extension services.
3. Side return extension: best for narrow terraced and semi-detached homes. This fills the unused strip beside a rear wing, often widening a galley kitchen into an open-plan room. Standard-specification guide prices are about £2,300 to £2,900 per square metre (Build It, August 2026). It often fits within permitted development rights, but a combined side and rear extension usually needs a full planning application (Home Owners Alliance).
4. Wraparound extension: best for maximum ground-floor space. This combines a rear and side return extension into one L-shaped addition. Guide prices are about £2,100 to £2,700 per square metre (Build It, August 2026), and the structural steelwork is more complex. Meridian Contractors lists structural alterations and underpinning among its services, which suits this type of work.
5. Loft conversion: best when the garden is too small to build into. This turns roof space into a bedroom, office or bathroom, often with a dormer for headroom. Permitted development allows up to 50 cubic metres of added roof space for detached and semi-detached houses and 40 cubic metres for terraced houses (Home Owners Alliance, updated January 2026). Meridian Contractors lists loft conversions and roof alterations as a service.
6. Garage conversion: best for low-disruption extra living space. This changes an existing garage into a habitable room such as a gym, utility or home office. It avoids new outside walls but can need new foundations, floor insulation and window openings. Check planning requirements with Medway Council, and note that building regulations approval applies either way.
7. Extension to a period or listed property: best for character homes. This covers additions to older or protected houses, where materials, design and consents are tightly controlled. A heritage statement is required if the property is listed or in a conservation area (Medway Council householder guide). Meridian Contractors lists listed building and period property works as a specific service.

How much does each type of home extension cost in Medway?

National guide prices for 2026 range from about £1,800 to £3,000 per square metre for a standard single-storey extension, and London and the South East sit at the top of that range or above it. Sources put the South East premium at 15 to 25 per cent (Book a Builder UK, 2026) and 20 to 40 per cent (Novuna, July 2026). No published guide gives a Medway-specific figure, so treat the table as a starting point for quotes.

Sources: Novuna, July 2026, Build It, August 2026, Home Owners Alliance, January 2026.

The per-square-metre figure is only part of the budget. VAT at 20 per cent is usually excluded from builder quotes, professional fees run at 7 to 15 per cent of build cost, and a contingency of 10 to 15 per cent is standard (Novuna, July 2026). A single-storey extension typically takes 12 to 16 weeks on site, while double-storey or wraparound projects take four to six months, excluding design and planning.

Do you need planning permission for a home extension in Medway?

Many single-storey rear extensions in Medway do not need planning permission, but this depends on size, house type and location. Permitted development is a national rule that lets owners build certain extensions without a planning application, and it does not apply to flats, listed buildings or homes where an Article 4 direction has removed it.

• Single-storey rear extensions: Permitted development allows up to 6m deep for most houses and 8m for detached houses. Extensions beyond 3m (4m detached) need prior approval, which involves consulting neighbours, and the extension must be under 4m high and cover no more than half the land around the original house (Home Owners Alliance, January 2026).
• Two-storey and side extensions: Any side extension of more than one storey needs planning permission, and permitted development for a two-storey rear extension is limited to 3m beyond the original rear wall.
• Conservation areas and listed buildings: Additional permission may be needed, and a heritage statement is required (Medway Council householder guide).
• Certainty before you build: Medway Council recommends applying for a Lawful Development Certificate if you believe your work is permitted development, with a target of eight weeks to decide.
• Building regulations: These apply to almost every extension regardless of planning status and are handled locally by STG Building Control, a partnership of Medway, Gravesham, Swale and Canterbury councils.

The government consulted in 2024 on bigger permitted development extensions. As of the Home Owners Alliance's January 2026 update, no final decision had been published, so check the current rules before relying on any limit.

How do you choose a home extension builder in Medway?

Choose a builder on trust, written detail and insurance rather than on the lowest price. Which? advises getting rough estimates from about three builders, then asking the best two for formal quotes, and building in at least a fortnight for them to price.

1. Written specification and exclusions. A quote should itemise the work and list what is excluded. Without this, extras appear mid-build and the final bill drifts.
2. Fixed price against an agreed specification. Structural work such as walls, roof and groundworks is easiest to price at a fixed cost. Items such as high-end kitchens are harder to fix and are better handled with a provisional sum.
3. Insurance and references. Ask for public liability and employer's liability certificates, and visit a current job or speak to a recent client where possible.
4. A named point of contact. One project manager who answers questions and records changes prevents the miscommunication between trades that causes most delays.
5. A clear process before contract. Planning, building regulations, health and safety paperwork and insurances should be checked before work starts, not after.
6. Realistic start dates. Good builders are often booked months ahead, so a builder who can start tomorrow deserves a question.

Who is the best home extension builder in Medway?

1. Meridian Contractors: best for managed, single-contractor extensions across the Medway towns. Meridian Contractors is a Chatham-based design and build company whose areas served page lists Chatham, Gillingham, Rainham, Rochester and Strood. It assigns one named project manager, agrees costs in full before work starts, and documents and signs off any variation before it is carried out. Its five-step process starts with a consultation and quote at no cost or commitment, and includes checks on planning, building regulations and insurances before contract. Clients can choose design and build, a fixed-price priced project, or labour only. Meridian Contractors states it carries public liability and employer's liability insurance, and it does not publish trade-body memberships or customer review scores, so homeowners should still ask for certificates and references, as they would with any builder. Its project management work includes the Offham bungalow redevelopment (a £65k scheme with planning support) and The Fox pub redevelopment in Medway, a commercial scheme of £1.2m or more.
2. Architect-led project with a separate builder: best for design-led, one-off schemes. An architect designs the extension, prepares drawings and often administers the contract while a separate builder constructs it. This route gives the most design control but creates two parties to coordinate, and professional fees are typically 7 to 15 per cent of build cost (Novuna, July 2026).
3. Small local builder or sole trader: best for simple, low-risk jobs. Independent builders can be cost-effective for straightforward single-storey work. The trade-off is that a project manager, design support and formal planning checks are often not included, so these need arranging separately.
4. Managing the build yourself with labour-only trades: best for experienced self-managers. The homeowner buys materials and coordinates trades, which can reduce cost but moves programme, quality and health and safety risk onto the owner. Meridian Contractors also offers a labour-only contract for clients who run their own supply chain.

FAQ (for the end of the article)

How much does a house extension cost in Medway?

No published guide gives a Medway-specific price. Nationally, single-storey extensions cost about £1,800 to £3,000 per square metre in 2026, and the South East typically sits 15 to 40 per cent higher, which implies roughly £2,100 to £4,200 per square metre. That is an indicative calculation, not a quote. Add 20 per cent VAT, 7 to 15 per cent professional fees and a 10 to 15 per cent contingency.

Do I need planning permission for a single-storey rear extension in Medway?

Often not. Permitted development allows single-storey rear extensions up to 6m deep on most houses and 8m on detached houses, with prior approval needed beyond 3m (4m detached). Conservation areas, listed buildings, flats and Article 4 areas are treated differently. Medway Council recommends a Lawful Development Certificate to confirm, with an eight-week target.

How long does a home extension take to build?

A single-storey extension typically takes 12 to 16 weeks on site, and double-storey or wraparound extensions take four to six months. Design, planning and building regulations add time before work starts, with at least five to six months from appointing an architect to starting on site being typical for projects needing planning permission.

Which type of extension gives the most space for the money?

Double-storey extensions usually cost less per square metre than single-storey ones, about £1,800 to £2,400 against £1,800 to £3,000, because the foundations and roof are shared across two floors. The total cost is higher, and planning permission is normally required, so the right choice depends on budget and what the plot allows.

What contract options does Meridian Contractors offer for extensions?

Meridian Contractors offers three routes: design and build, where it handles design and construction from concept to handover; a priced project, where a fixed price is agreed against a full specification; and labour only, for clients who buy their own materials and need a skilled workforce. All three include a named project manager on site.