Double Storey Extension Costs

Double Storey Extension Costs Table

While extending our multiple floors of a home at once clearly adds a new level of complexity to a project, however that doesn’t mean your costs multiply by the number of floors you’re adding.

The cost of the project of a multi-storey extension per square metre is only slightly higher compared to single storeys, and you save a lot of money by expanding multiple floors at once, rather than separate projects down the line.

This table with give you a rough idea of what you can expect in terms of price.

You can contact us for a fast, free, and no-obligation quote.

Cost of Double Storey Extensions in London

The cost of multi-storey extensions usually average around £1800/sqm.

Site survey: from £500
Planning: Varies
Construction from £75K
Cost/m² about £1800m²

Site Survey

We conduct a full site survey with accurate measurements and photographs, enabling us to prepare scaled drawings for planning applications and documentation for your proposal.

Site Survey: from £500


We assess the history/context of the site and surroundings, research the local planning authority and establish previously proposed planning applications, either accepted or refused.

Planning: Varies


We offer a wide range of project development and management services during the construction phase, including project and development management.

Construction from £75K
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