What Should Be Included in a Builder's Quote?

A builder's quote should make it clear what you are paying for, what is excluded, how the price has been built up, and what could change before the final bill. If it does not, you are being asked to make a decision on trust rather than evidence.

This is a common problem for UK homeowners. Two builders can visit the same property and send quotations that look similar at first glance, but one may include scaffolding, waste removal, finishing, VAT and Building Control support, while the other may leave those items vague or completely missing. The cheaper quote is not always cheaper once the gaps are filled.

This guide explains what should be included in a builder's quote, how to spot missing detail, and what to ask before you sign. If you already have a quotation, you can also use KnowMyQuote's free Quote Health Check to help identify unclear wording, missing allowances and risky exclusions.

Common mistakes

Accepting a one-line price. A quotation that says "extension works - £42,000" is not detailed enough. You need to know what works are included, which drawings or specification the builder has priced from, whether materials are included, what level of finish is assumed, and whether VAT is included. A one-line quote gives you very little protection if a dispute arises later.

Assuming all builders have priced the same work. Homeowners often compare totals without checking whether each quote is based on the same scope. One builder may have allowed for plastering, skirting boards, electrics and decorating. Another may have priced only the shell and first-fix services. If the scope is not identical, the headline total is not a fair comparison.

Ignoring provisional sums and allowances. A provisional sum is an estimated amount for work that has not been fully defined. An allowance is often used for items you will choose later, such as tiles, sanitaryware, kitchen units or flooring. These are not automatically bad, but they need to be realistic and clearly stated. A quote packed with low allowances can look attractive but lead to extra costs later.

Not checking VAT. The quote should state whether VAT is included, excluded, or not applicable. If a VAT-registered builder quotes "£30,000 plus VAT", the cost to you is different from a quote that says "£30,000 including VAT". Always ask for this to be written clearly.

Overlooking exclusions. Good exclusions are useful because they show what the builder has not priced. Risky exclusions are vague phrases such as "subject to site conditions" or "extras as required" with no explanation. You need to understand whether common items such as skips, scaffolding, structural engineer details, Building Control fees, decorating, making good, landscaping and service upgrades are included or excluded.

Failing to agree the payment schedule. A builder's quote should explain when payments are due and what each payment relates to. Large upfront payments without a clear reason are a warning sign. For many projects, payments should be linked to progress or agreed milestones rather than vague dates.

Real examples

Example 1: Two kitchen extension quotes that are not like-for-like.

Imagine you receive two quotes for a small rear extension. Builder A quotes £48,000 including VAT. Builder B quotes £43,500 including VAT. Builder B looks £4,500 cheaper.

On review, Builder A's quote includes foundations, drainage alterations, steel installation, rooflight installation, plastering, electrical first and second fix, basic kitchen plumbing, three skips, scaffolding and making good around the new opening. Builder B's quote includes the main building shell but excludes electrical work, plumbing alterations, decoration, skips and Building Control attendance.

If the excluded items in Builder B's quote later cost, for example, £7,200, the apparent saving disappears. The issue is not that Builder B is necessarily a bad contractor. The issue is that the quote does not cover the same work.

Example 2: The low bathroom allowance.

A homeowner gets a quote for a bathroom refurbishment at £8,600. It includes an allowance of £900 for all tiles, taps, shower fittings, basin, toilet and vanity unit. The homeowner then chooses mid-range products that total £2,150.

That creates an extra £1,250 before any additional labour, delivery charges or changes to plumbing are considered. A better quote would separate labour, materials supplied by the builder, client-supplied items, and realistic allowances for sanitaryware and finishes. It would also explain what happens if the homeowner chooses products above or below the allowance.

Example 3: Scaffolding and waste left out.

For a roof and chimney repair, Builder A quotes £6,400 and includes access scaffolding, waste disposal, leadwork, replacement tiles as required up to a stated quantity, and making good disturbed mortar. Builder B quotes £5,750 but states "scaffold by client if required" and "waste not included".

If scaffolding later costs, for example, £1,100 and waste removal costs £280, Builder B's real cost becomes higher. More importantly, the homeowner has to organise critical items that should have been discussed before work began.

What to do instead

1. Ask for a written quotation, not just an estimate. A quote should be a firm offer based on defined information. An estimate is a guide and may change. Some projects genuinely need provisional sums, but the document should still be clear about what is fixed and what is not.

2. Make sure the quote names the documents used. For larger works, the quote should refer to drawings, structural calculations, specifications, planning documents or a schedule of works. If the builder priced from a conversation only, ask them to confirm the scope in writing.

3. Request a breakdown by trade or work stage. You do not need every screw itemised, but the quote should separate major areas such as demolition, groundwork, drainage, brickwork, roofing, electrics, plumbing, plastering, joinery, decorating and waste. This makes gaps easier to spot.

4. Check whether labour, materials and plant are included. Plant may include diggers, mixers, access towers, lifting equipment or specialist tools. Access and temporary works can be expensive, so they should not be left vague.

5. Clarify VAT in writing. Ask for wording such as "total price including VAT" or "VAT to be added at the applicable rate". If the builder says VAT does not apply, ask them to confirm why, for example if they are not VAT registered.

6. List all exclusions and client responsibilities. If you are expected to supply tiles, appliances, parking permits, access, welfare facilities or skips, it should say so. If the builder is responsible, it should also say so.

7. Check provisional sums and allowances. Ask whether the allowance is realistic for the finish you expect. For example, an allowance of £25 per square metre for tiles gives a very different result from choosing tiles at £60 per square metre.

8. Agree how variations will be handled. A proper quote should explain that changes must be priced and approved before the work is carried out, except in genuine emergencies. Verbal changes are a common source of disagreement.

9. Confirm timing and payment terms. Ask for an expected start date, estimated duration, working hours, key milestones and payment schedule. A payment request should match work completed or materials reasonably ordered.

10. Compare quotes side by side. If you have two or more quotations, use a simple table with the same headings. You can also read more practical homeowner guidance on our other quotation guides.

What a builder's quote should include

A useful builder's quote should include enough detail for you, the builder and any professional adviser to understand the agreement. At a minimum, look for the following:

• Builder's details: trading name, address, company number if applicable, contact details and VAT number if VAT registered.
• Client and site details: your name, the property address and any access notes that affect the work.
• Date and quote validity: how long the price remains open for acceptance, especially where material prices may change.
• Description of the works: a clear summary of the project and the areas of the property affected.
• Basis of the price: drawings, specification, site visit, photographs, structural design or written schedule used to prepare the quote.
• Detailed scope: what is included under each work section.
• Materials and finish level: brands, product ranges, dimensions, quantities or quality assumptions where relevant.
• Labour and subcontractors: whether specialist trades such as electricians, plumbers, roofers or plasterers are included.
• Access, plant and temporary works: scaffolding, skips, protection, dust control, temporary supports and welfare arrangements.
• Professional and statutory items: planning conditions, Building Control inspections, structural engineer input, party wall matters and certificates, stating who is responsible for arranging and paying for them.
• Provisional sums and prime cost allowances: clearly labelled with realistic figures.
• Exclusions: anything not included, written in plain English.
• Programme: expected start date, duration and any key dependencies.
• Payment schedule: deposit, stage payments, final payment and retention if agreed.
• Insurance and guarantees: public liability insurance, workmanship warranty and product guarantees where applicable.
• Variation process: how changes are requested, priced and approved.

If a quote is missing several of these items, ask for a revised version. A professional builder should not object to reasonable clarification.

Quote, estimate and specification: what is the difference?

Homeowners often use the words quote and estimate as if they mean the same thing, but they are different in practice.

A quotation should be a fixed price for a defined scope of work, subject to stated exclusions and assumptions. If you accept it, it can form part of the contract between you and the builder. That is why detail matters.

An estimate is an informed approximation. It may be useful at an early stage, before drawings, structural details or product choices are available. However, you should be cautious about starting substantial building work on an estimate alone unless the basis for changes is very clear.

A specification is the document that describes what is to be built and to what standard. For smaller jobs, the specification may be included within the quote. For larger projects, it may be a separate schedule prepared by an architect, designer, surveyor or project manager.

The strongest position is to have a clear specification and ask each builder to price the same document. This reduces misunderstandings and helps you compare quotations fairly.

Red flags in a builder's quote

Some warning signs are obvious, such as no written document or pressure to pay immediately. Others are more subtle.

Be careful with wording such as "all building works included" if the quote does not say what those works are. Broad language can feel reassuring but may be difficult to rely on later. Similarly, phrases such as "standard finish" or "builder's choice" should be clarified. Your idea of a standard finish may not match the builder's.

Watch for unusually low provisional sums. If a loft conversion quote includes a small allowance for steelwork before structural calculations have been completed, that figure may change. The right response is not necessarily to reject the builder, but to ask what has been assumed and when the cost will be confirmed.

You should also be cautious if the payment terms are front-loaded. A modest deposit may be reasonable where materials need to be ordered, but the quote should explain what it covers. If a builder asks for a large payment before any work or materials are evident, ask more questions.

Finally, check whether the quote is addressed to you and your property. Reused templates are normal, but a quotation should still be specific to your job. If it contains another client's address, old dates or irrelevant items, ask for a corrected version before relying on it.

How to compare builders' quotes fairly

When comparing quotes, do not start with the total. Start with the scope. Create a simple comparison table with rows for foundations, drainage, structure, roof, windows and doors, electrics, plumbing, plastering, joinery, decoration, floor finishes, waste, scaffolding, VAT and exclusions.

Then mark each item as included, excluded, provisional, allowance or unclear. This quickly shows whether one builder is cheaper because they are more efficient, or because they have not priced the same job.

If one quote is much lower, ask the builder to confirm specific items in writing. A good question is: "Can you confirm this price includes everything shown on drawing X and the specification dated Y, except the exclusions listed?" Another useful question is: "If this becomes an extra, how will it be priced and approved?"

You may also want to understand who you are dealing with. KnowMyQuote explains more about its role and approach on the about page, and you can contact us if you need help understanding the next step.

Frequently asked questions

Before you sign

Before you accept a builder's quote, make sure the document is specific, complete and easy to understand. It should state what is included, what is excluded, what is provisional, when payments are due, and how changes will be agreed. If you have to guess, the quote needs more detail.

You do not need to become a construction expert, but you do need enough information to make a safe decision. If you already have a quotation, upload it for a free KnowMyQuote Quote Health Check. If you have two quotations, we can help you compare them side by side and highlight the differences before you commit.