Southampton price guide
House extension quotes in Southampton
Typical local pricing runs £1,950–£3,200 per m² of new floor area, excluding VAT and kitchen fit-out. Here is what drives that range in Southampton, and what to check on the quotation in front of you.
Indicative Southampton range
£1,950 – £3,200
per m² of new floor area, excluding VAT and kitchen fit-out. Based on a local cost index of 1.10 against the UK average.
Why Southampton pricing differs
South coast rates sit above the national average, and marine exposure drives render, roofing and window replacement demand.
Victorian terraces in Portswood, 1930s semis in Bitterne, and a large waterfront apartment stock.
Planning and consent
Southampton City Council conservation areas cover Bedford Place and Old Town; coastal flood zones affect some ground works.
What to check on a house extension quotation
- Foundation depth allowed for, and the rate if a deeper dig is needed
- Whether structural steel, engineer's fees and building control are inside the price
- The glazing allowance, stated per m² or per unit
- Which items are provisional sums rather than fixed prices
Areas we see quotes from
Homeowners across Portswood, Bassett, Bitterne, Shirley, Woolston and the wider Hampshire area use KnowMyQuote to understand what a contractor has actually priced before committing.
Frequently asked questions
How much does house extension work cost in Southampton?
Local pricing typically runs £1,950–£3,200 per m² of new floor area, excluding VAT and kitchen fit-out, based on a higher-than-average cost index of 1.10 for Southampton.
Why do quotes in Southampton differ so much?
Because they rarely cover the same scope. South coast rates sit above the national average, and marine exposure drives render, roofing and window replacement demand. Two quotes for the same job can exclude different items, which is why comparing exclusions matters more than comparing totals.
Do I need planning permission in Southampton?
Southampton City Council conservation areas cover Bedford Place and Old Town; coastal flood zones affect some ground works. Always confirm with the local authority before committing, and apply for a Lawful Development Certificate where the work is permitted development.
How many quotes should I get?
Three, all priced against the same drawings and written specification. Without a common document you are comparing three different buildings, not three prices.
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