Modular House Extensions
A finished room, built in a factory and lowered behind your house in a single morning.
Get a quote- Design8 to 14 weeksDrawings, planning where needed, building control
- Factory build4 to 6 weeksYour base goes in at home meanwhile
- Crane day1 dayThe room arrives finished and is set on the base
- Moved in2 to 6 weeks laterWall opened, services joined, decorated
What turns up on the lorry
Not a kit. The module leaves the factory insulated, glazed, wired and plastered. A crane sets it on a base dug while it was being made, and by the afternoon your house has a new room.
- Modular kitchen extensions plumbed, wired and often fitted before it leaves
- House extension pods one small module for an office, bedroom or shower room
- Modular loft conversions a new top floor lowered onto the house
Three widths decide how your room travels
Up to this width a module travels as an ordinary load. Most pods do.
Past 2.9 m the police get two working days of notice. Past 3.5 m an attendant rides along.
Wider still needs National Highways to approve. Rooms are split in two long before that.
Then comes your street. See the delivery and crane guide.
Source
Width thresholds for abnormal loads on roads in Great Britain: GOV.UK, Transporting abnormal loads.
What it costs
Expect £2,100 to £3,300 per square metre including VAT, base and one-day lift included. London and the South East usually cost 20 to 40% more. National figures: a guide, not a quote.
| Floor area | Arrives as | Guide price, including VAT |
|---|---|---|
| 12 m² Pod | One module | £30,000 to £39,500 |
| 20 m² Living room | One module | £42,000 to £58,000 |
| 30 m² Living room | Two modules | £63,000 to £87,000 |
| 40 m² Kitchen-diner | Two modules | £100,000 to £132,000 |
How long you are without a kitchen
The old wall stays up until the new room is weathertight, so the mess indoors is squeezed into the two to six weeks after crane day. Keep the old kitchen connected until the new one is live and you may go without for only a few days.
Permission, and the street
Planning treats a factory-built room like any extension. At the back of a house in England, one storey reaching no more than 3 m out (4 m if the house is detached) usually counts as permitted development. Building regulations always apply. Scotland sets its own limits and wants a building warrant first.
The surprise is the highway: a crane in the road needs a council licence, and a closure can take weeks to arrange.
Before you ring anyone
Is a modular house extension cheaper than building one?
Rarely. The base, drains and finishes cost the same, and the crane and haulage are extra. You are buying a shorter build. See the cost calculator.
What if a crane cannot reach my garden?
The room comes in smaller pieces, or as panels carried through. Our delivery guide shows what a firm will measure.
Will I need planning permission?
Often not. Size and position decide it, not how the room was made.
Does it feel like part of the house?
It should. Floor levels are matched in the factory, and plaster and flooring run through the opening.
Get a quote for your extension
Three short steps, about a minute. Start with the postcode so we know which firms can reach you.
This is a free introduction service, not a modular extension firm. We look for a firm that builds this type of extension where you live and tell you its name. Your details go to that firm only when you say yes.
Thank you. That is everything we need.
- We look for a firm that builds and cranes in this kind of extension in your area, usually within a working day.
- We email or phone you with the firm's name. Nothing has been passed to them at that point.
- If you are happy, we send your enquiry on and they arrange to see the house and the access. We never send marketing.