Finding a Builder in Cardiff
Cardiff has one of the largest concentrations of building contractors in Wales, which means plenty of choice — but also more risk of unreliable operators. The key differentiator between good and bad builders is references, insurance, and written contracts. All three are non-negotiable for any significant project.
For projects over £10,000, look for FMB (Federation of Master Builders) or TrustMark registration. Both schemes require members to pass vetting checks including insurance verification and customer satisfaction assessments. Search fmb.org.uk or trustmark.org.uk by postcode.
For smaller jobs, personal recommendations from neighbours or Cardiff-specific community groups are often the best starting point. Ask specifically for recommendations for the type of work you need — a builder known for extensions may not be ideal for internal refurbishments.
Getting Quotes in Cardiff
Always get a minimum of three quotes for any job over £2,000. In Cardiff, given the density of contractors, getting four or five quotes for larger projects is practical and worthwhile.
Ensure quotes are like-for-like in specification:
- Same materials (e.g., specific brick type, tile spec)
- Same scope (e.g., whether skip hire and scaffolding are included)
- Same finish standard (e.g., plastered and painted vs. first fix only)
If one quote is significantly cheaper than others, ask what has been excluded. Price differences usually reflect scope differences, not contractor quality.
Contracts and Payment Structure
Never start significant building work in Cardiff without a written contract. At minimum it should cover:
- Full scope of works with specification
- Start and projected completion dates
- Stage payment schedule tied to milestones
- Variation procedure (how extra work is priced)
- Retention (5-10% held until snagging is resolved)
- Dispute resolution process
Stage payments are important. A typical structure is 10-25% deposit on signing, then payments at specific milestones (e.g., groundworks complete, roof on, first fix done), with final payment on completion and snagging sign-off.
Cardiff Builder Costs 2026
Cardiff is at the higher end of Welsh pricing, reflecting higher demand and costs. Typical rates in 2026:
- Skilled builder day rate: £220–£320 per day
- Single-storey extension: £1,700–£2,400 per sq m
- Loft conversion (rooflight): £35,000–£50,000
- Loft conversion (dormer): £45,000–£65,000
- Full house refurbishment: £600–£1,200 per sq m
Always budget a 15-20% contingency on top of the quoted price. In Cardiff's older terraced housing stock (particularly in Roath, Canton, Pontcanna), unexpected structural issues are common once walls are opened.
Planning Permission in Cardiff
Most extensions and loft conversions fall under permitted development rights, but Cardiff Council has specific conditions in conservation areas (Pontcanna, Cathedral Road area, parts of the Bay). Always check with Cardiff Council's planning department before starting work.
Your builder should advise on this, but the responsibility for obtaining any required consent rests with you as the homeowner — not the contractor.