How to Choose a Builder for Your House Extension in Wirral (And Avoid the Cowboy Ones)

Cowboy builders cost UK homeowners an estimated £3.5 billion every year. The Federation of Master Builders reckons that more than half of UK homeowners who have hired a builder have run into a rogue trader at some point. Wirral has some genuinely good house extension builders. It also has people who will take a large deposit and become very difficult to contact. Reading quotes alone will not tell you which is which. So before you hand over any money, here is what to check.

Check they are a registered limited company

If a builder says they operate as a limited company, check it yourself at Companies House. Takes two minutes. You want to see the company is active, accounts are filed, and the director names match who you are actually dealing with.

If there is no registered business and something goes wrong, chasing them in court is considerably harder. CNR Construction Ltd is registered at Companies House and you can look it up right now. Any extension builder in Wirral who will not give you their company registration number is telling you something.

Check their Google reviews properly

A 5-star average looks good. What tells you more is whether the reviews are recent, how many there are, and whether they describe actual work in any detail.

Look for reviews from the last 12 months that name the job, mention the team, or describe something specific about the project. Vague four-word reviews from profiles with no photo mean very little. Longer reviews from people who clearly had real work done are much harder to fake. Also look at how the business responds. Generic copy-paste replies are a sign. Responses that acknowledge the specific job and the client by name are a better indicator of how the company actually operates.

CNR Construction's Google reviews are there if you want to read through them before making any decisions.

Get a proper written quote, not a ballpark figure

A verbal estimate is not a quote. Before any work starts, you need a written, itemised document that separates materials from labour, sets out payments tied to actual build milestones, and confirms what is in the price.

Things that routinely get excluded from the headline figure and added back once the job is live: building control fees, scaffolding, skip hire, structural engineer costs. Ask about all of those before you sign. If a builder cannot put a detailed written quote together within a reasonable timeframe, that is a preview of how communication is going to go once they are on your property. A written quote is not a favour. It is the minimum standard for anyone doing this professionally.

Red flags on payment

Ten to fifteen percent deposit is standard. Requests for 30, 40, or 50 percent upfront before the foundations have even gone in are a serious warning sign. Builders asking for that kind of money either have a cash flow problem or plan to use your deposit to fund another job first.

Pay by bank transfer, get a receipt for everything, and tie each stage payment to a completed milestone rather than a date. "I need the next payment on Friday" is not a milestone. "Roof structure completed and signed off by building control" is.

Check their recent work, not just a portfolio page

Two photos from four years ago is not evidence of anything current. Ask specifically for jobs completed in the last 12 months. If possible, visit a live site or a recently finished one. A builder who is confident in their work will not have any problem with that.

Ask for phone numbers for two recent clients, not written testimonials. A testimonial takes thirty seconds to fabricate. A number for someone who had their extension done last spring is harder to fake. CNR's project gallery has recent Wirral and Merseyside jobs with full before and after images, including a rear extension in Willaston completed in 2025 and the Morton project finished earlier this year.

Questions to ask before you sign anything

Get answers to these before committing to anyone:

• Are you VAT registered? Turning over more than £90,000 a year and not registered needs an explanation.
• Can I see your public liability insurance certificate? Not confirmation it exists. The actual certificate, cover level, and expiry date.
• Who is on site day to day? You, or subcontractors? If subcontractors, who are they?
• How do you handle unexpected structural problems mid-build? What is the process for changing the quoted price?
• Contact details for two clients from jobs finished in the last 12 months?

Any competent builder will answer all of those without getting defensive. Evasion is an answer in itself.

Why we would rather you asked us all of these

CNR Construction is a registered limited company, fully insured, and has been building extensions across Wirral for over 11 years. Building Regulations sign-off is handled in-house, so you do not have to chase separate approvals yourself.

Ollie and the team have built up a track record of Wirral extension work that you can read about before picking up the phone. The project gallery and Google reviews are both there. Have a look. Then if you want to talk about your extension, get in touch here.

Frequently asked questions