House Extension Checklist for Maidstone Homeowners
Most Maidstone homeowners commissioning their first house extension don't know what "good" looks like — and that's fair. A house extension is a five- to six-figure decision made once every 10–20 years, with 3 quotes that all look reassuring on the front page.

Get a Maidstone quote
Free site visit. Itemised written quote in 5 working days.
Before you request any Maidstone quote
Sort these five things first — you'll get much more accurate quotes and shorten the whole process by weeks.
- • Rough scope: rooms affected, must-haves, nice-to-haves in writing
- • Rough budget band — £X to £Y, all-in — so builders can spec to it
- • Site access: parking, skip location, working hours you can accept
- • Planning status: existing PP, PD certificate, or fresh application needed?
- • Timing: earliest start month, any hard deadlines (baby / wedding / school year)
Quote-comparison checklist — line-by-line
The written quote should let you compare like-for-like across 3 builders. If it doesn't include every one of these, ask for it in writing before signing.
- • Itemised cost by trade (not a single "labour and materials" number)
- • Written spec: make, model, finish for every fitting
- • Kitchen / bathroom / sanitaryware supply — included or PC sum?
- • Programme with week-by-week milestones
- • Payment schedule tied to stage completion, not calendar dates
- • Public liability and employer's liability insurance certificates
- • Workmanship warranty terms (min 5 years) — in writing
- • Contingency line, held back — not spent unless needed
- • VAT status and split (reduced-rate lines flagged if applicable)
Contract clauses that protect you in Maidstone
Once you've picked a builder, the contract is where you get protected — or not. These clauses should be in every Maidstone house extension contract.
- • Liquidated damages on programme slip caused by the builder
- • Retention (typically 5%) held for 6 months against snags
- • Change control — variations in writing before work proceeds
- • Dispute resolution route (mediation before litigation)
- • Termination for cause on both sides (not just the builder's)
- • Copy of the JCT Minor Works Building Contract or equivalent
Red flags on a Maidstone quote
Any of these should stop you signing until you've had a proper explanation in writing.
- • Deposit above 15% — nobody legitimate needs half up front
- • "From £X" pricing — real quotes are fixed, not open-ended
- • No insurance certs offered voluntarily with the quote
- • No previous-client references you can call
- • No mention of building regs / planning obligations
- • Vague "PC sums" for major line items (kitchen, sanitaryware)
In short
A house extension in Maidstone goes well when the pre-build, quote-comparison, contract-clause and red-flag checklists are all sorted before you sign. Bring this checklist to every quote — including ours.
Maidstone design FAQs
How many Maidstone builders should I get quotes from?
Three is the sweet spot — enough for meaningful comparison, few enough to stay organised. All three should be local (14 miles (~30-minute drive) radius) so distance loadings and site-visit friction are comparable.
What's a reasonable deposit in Maidstone?
10% on contract signing is standard. Anything over 15% is a red flag — the builder should have working capital for materials until the first stage payment.
Should I use a JCT contract or the builder's own?
JCT Minor Works or JCT Home Building Contract — both are industry-standard, fair to both sides, and cheap to buy. A builder-drafted contract usually skews toward the builder.
Who signs off building control at the end of my Maidstone house extension?
Either Maidstone Borough Council's Building Control team or an Approved Inspector. The final certificate is a legal document you'll need if you ever sell — keep it filed with the deeds.
