How to Select a Renovation Contractor in London: A Client's Guide

The contractor selection process in London is routinely mismanaged by clients, often with significant financial and personal consequences. Most clients use price as the primary selection criterion. Price is important, but it is the wrong primary criterion. Here is a better approach.

Why price is the wrong primary criterion

A contractor who wins work on the lowest price has, by definition, submitted a price that competitors considered too low to deliver the work profitably at the required standard. There are only a few ways to reconcile this:

• —The low bidder genuinely has lower costs (sometimes true — but usually marginal)
• —The low bidder has miscalculated (common — and the cost falls on the client when variations appear)
• —The low bidder intends to recover margin through variations and claims (common)
• —The low bidder will compromise on quality or programme to restore margin (common)

This is not conjecture. It is the documented pattern in construction procurement globally, and residential renovation in London is not an exception.

What to evaluate instead

Track record. Has the contractor completed projects at a similar scale and specification? Can they show you completed work — not renders, not aspirational photography, but the finished product? Will they give you contact details for recent clients you can call?

Financial stability. A contractor who fails financially mid-project is a serious problem. Ask for their most recent accounts (filed at Companies House, publicly accessible). Look at the turnover trend, the net profit margin, and whether they have significant net assets.

Key people. Who will actually be running your project? The director who won the job will not be on site every day. Meet the project manager and site manager who will be. Assess whether they are competent and whether you can work with them for the duration of the project.

References. Ask for references from the last three completed projects at a similar scale. Call them. Ask: did the project complete on time? Did it come in on budget? Were variations reasonable and well-managed? Would you use this contractor again?

Programme credibility. Does the proposed programme reflect a realistic assessment of the scope, or is it compressed to win the job? Ask the contractor to walk you through the programme assumptions.

Insurance. Contractors must carry public liability insurance (minimum £2m, preferably £5m+ for high-value projects), employers' liability insurance (mandatory), and contract works/all-risks insurance. Ask for certificates. Check they are current and that the insured value is appropriate.

The tender process

For projects above £100,000, a formal tender process is worth the effort. Provide all bidding contractors with identical tender documents: scope of works, specification, any drawings, the contract form you intend to use, and a programme requirement. Evaluate bids on a like-for-like basis.

Be suspicious of very large price differences between bidders. If one contractor is 40% below the others, they are either fundamentally mispricing the job or planning to recover the shortfall through variations.

Common red flags

• —Pressure to decide quickly ("I have another job I need to commit to")
• —Resistance to written contract or JCT form
• —Requests for large upfront payments
• —Unwillingness to provide references
• —No clear answer on who will manage the project day-to-day
• —No professional indemnity insurance for design work being undertaken

ASAAN's approach

ASAAN operates at the top end of the London renovation market. We compete on quality, capability, and track record — not on being the cheapest quote. We welcome reference requests, site visits to completed projects, and detailed questions about how we work.

If you are evaluating contractors for a significant renovation project and would like to include us in your tender process, contact us.