North West regional pricing

How Much Does a Builder Cost in Sefton?

Updated prices for . Sefton prices are typically 1% above the national average.

14 services priced
North West region
Updated

Price summary

Sefton Price Summary

Service Low Average High
Single Storey Extension £30,270 £50,450 £80,720
Double Storey Extension £50,450 £85,765 £141,260
Loft Conversion £25,225 £45,405 £75,675

Prices include labour and materials. VAT may apply. Based on North West regional pricing.

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Full pricing

All Builder Prices in Sefton

Every price adjusted for Sefton using a 1.009x cost multiplier, rounded to the nearest £5.

Single Storey Extension

Low

£30,270

Average

£50,450

High

£80,720

8-12 weeks

Double Storey Extension

Low

£50,450

Average

£85,765

High

£141,260

12-20 weeks

Loft Conversion

Low

£25,225

Average

£45,405

High

£75,675

6-10 weeks

Garage Conversion

Low

£8,070

Average

£15,135

High

£25,225

2-4 weeks

Porch Build

Low

£2,520

Average

£4,540

High

£8,070

1-2 weeks

Garden Wall

Low

£805

Average

£1,515

High

£3,025

2-4 days

Knock Through Internal Wall

Low

£1,010

Average

£1,815

High

£3,530

2-4 days

Chimney Breast Removal

Low

£1,210

Average

£2,020

High

£3,530

2-4 days

Underpinning

Low

£5,045

Average

£12,110

High

£25,225

2-4 weeks

Damp Proof Course

Low

£505

Average

£1,210

High

£2,520

1-3 days

New Build Garage

Low

£10,090

Average

£18,160

High

£30,270

3-5 weeks

Outbuilding or Garden Room

Low

£12,110

Average

£25,225

High

£50,450

3-6 weeks

Structural Steelwork (RSJ Installation)

Low

£1,010

Average

£1,815

High

£3,025

1-2 days

Patio or Decking Build

Low

£1,515

Average

£3,530

High

£7,065

3-5 days

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Regional comparison

How Sefton Compares

Average cost of single storey extension across regions.

Sefton
+1% £50,450
National Average
baseline £50,000
London
+24% £62,150

Local insights

What Affects Builder Costs in Sefton?

Sefton's housing stock is dominated by Victorian and Edwardian terraced houses, with large numbers of properties across the wider metropolitan area and surrounding towns. These older homes often present challenges for builder work, including limited access, older infrastructure and the need for more preparation. Properties that haven't been updated in decades tend to push costs toward the higher end of the ranges shown above.

The North West consistently sits below the national average for trade costs, and Sefton is no exception. Labour rates here are around 1% above the UK average and considerably lower than London or the South East. This reflects both the lower cost of living and a healthy supply of qualified builder professionals across the region. That said, prices can still vary by 30-50% between different tradespeople for the same job, making multiple quotes essential.

Several factors affect builder costs in Sefton. Back-to-back terraces may have limited access that makes work more complicated and expensive. Properties with solid walls rather than cavities can add to the difficulty. For larger projects, expect costs at the higher end — a double storey extension in Sefton typically runs £50,450 to £141,260. Material and product choices also make a significant difference to the total.

When getting quotes in Sefton, aim for a minimum of three from different qualified professionals. Ask each one to visit and assess the work rather than quoting over the phone. A good builder will check the existing conditions, identify potential complications, and provide a clear cost breakdown. Be wary of quotes that seem significantly cheaper than others — they may be cutting corners on materials or quality. Always check qualifications, insurance and recent reviews before hiring.

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More services

Other Services in Sefton

Explore costs for other services in the Sefton area.

40 services — scroll to explore

Common questions

Frequently Asked Questions

Common questions about builder costs in Sefton.

How much does a builder cost in Sefton in 2026?
Single Storey Extension in Sefton typically costs between £30,270 and £80,720, with the average being around £50,450. Prices vary depending on the scope of work, materials used, and the specific requirements of your property.
Are builder prices cheaper in Sefton than London?
Sefton prices are 1% above the national average, though still £11,700 cheaper than London for single storey extension.
How do I find a good builder in Sefton?
Get at least three quotes from different tradespeople, check recent reviews, and ask whether the quote includes VAT and everything you need. A detailed written quote that breaks down all costs is a good sign. Always check qualifications, insurance and recent reviews before hiring.
What affects builder prices in Sefton?
The main factors are the scope and complexity of what you need, the options and products chosen, and local market rates. Sefton rates are 1% above the national average. Getting multiple quotes is the best way to ensure a fair price.
Do builder prices include materials in Sefton?
The prices shown on this page include all typical costs. However, when getting real quotes, always confirm what is and isn't included. Some tradespeople break out costs separately, while others give an all-in price. Ask for a detailed breakdown before agreeing to any work.