Modular House Extensions
Where a traditional extension means months of building work against the house, a modular extension is manufactured off site and installed in a fraction of the time — either linked to the house or as a detached building in the garden.
Extra space without living on a building site
The decision is usually whether to link the new space to the house or keep it detached. Detached is simpler — no structural opening, no party-wall complications — and is often what people actually need when they want a bedroom, office or living room.
- Detached garden building, or a linked structure alongside the house
- Bedroom, office, living room or gym layouts
- Shower room or WC where drainage allows
- Cladding matched or contrasted with the existing house
- Short site programme — base, craneage and connections
- Relocatable if you move or reconfigure the garden
Example configurations
Each P600 module is approximately 13 m². Modules join side by side and stack over two storeys.
A single extra room — office, bedroom or snug.
Living space with a shower room, or two separate rooms.
A full annexe-scale extension with bedroom, bathroom and living area.
Modular House Extensions — key facts
- Product
- P600 modular building
- Module dimensions
- 5900mm × 2200mm (5.9m × 2.2m)
- Module footprint
- approx. 12.98 m²
- Price per module
- £10,750 + VAT (£12,900 inc. VAT)
- Configuration
- Single module or multiple connected modules
- Storeys
- Up to two storeys, subject to final project design
- Delivery
- UK mainland and Northern Ireland, included in the price
The Adacon P600 modular building measures 5.9m × 2.2m (5900mm × 2200mm) with a module footprint of approx. 12.98 m², and costs £10,750 + VAT per module. Each module can include a kitchen, toilet, shower, internal partitions, windows, doors, lighting, sockets and a consumer unit, and modules can be joined side by side or stacked to two storeys.
What's available
Whether a building can be used as a permanent dwelling, and what Building Regulations, planning permission, foundations and energy-performance requirements apply, depends entirely on your site and how the building will be used. We make no blanket claim that a standard configuration constitutes a compliant dwelling — this must be confirmed for your specific project.
Modular House Extensions — common questions
Design your extension
Choose the size, rooms and cladding and get an estimated price.
Related homes
Modular granny annexes and garden annexes — self-contained bedroom, shower room and kitchenette, delivered fitted out and installed in the garden.
Modular guest accommodation for the garden — a self-contained guest room with shower room and kitchenette, insulated and delivered fitted out.
Two-storey modular homes built by stacking P600 modules — living space below, bedrooms above, with internal or external stairs and an optional balcony.
Design options for this build
All design optionsOther things we build
What do you need to build?Useful guides
Yes — P600 modules can be stacked to create two-storey modular offices, welfare blocks and clubhouses, with an internal or external staircase.
An Adacon P600 module costs £10,750 + VAT fully fitted, with UK mainland and NI delivery included. See what drives the price of a modular building.
Whether a modular building needs planning permission depends on its use, size, siting and duration. Read how the common cases usually work in the UK.