SpectraResource · estimating
Estimate the job you can describe.
Make materials, labour, waste, assumptions and revisions inspectable before a price is released.
Published by Spectra · no named expert reviewer is claimed · last reviewed 17 September 2026 · operational guidance, not technical, legal or safety certification.
The practical answer
An estimate explains its inputs and is revised when its scope changes. The synthetic numbers below are instructional only; they are not market rates or a pricing recommendation.
Inputs
Build a visible basis for the number.
List material, anticipated waste, labour, finishing, bought-in work, installation and overhead according to your own rules. Record whether dimensions were measured, supplied or assumed.
- Cost basis and evidence source
- Waste or yield assumption
- Labour allowance and owner
- Markup or margin definition
- Revision reason and date
Worked sample
Calculate a fictional fascia estimate step by step.
Synthetic sample: NQC-014 uses material input £480, allowance for waste £48, workshop labour £220, bought-in component £310 and installation allowance £190. The illustrative direct-cost basis is £1,248. A 25% markup illustration gives £312 gross profit and a £1,560 selling-price basis before any business-specific treatment.
| Input | Synthetic amount | Note |
|---|---|---|
| Direct cost basis | £1,248 | 480 + 48 + 220 + 310 + 190 |
| Illustrative markup | 25% | £1,248 × 0.25 = £312 |
| Illustrative selling basis | £1,560 | Not a quote or tax treatment |
Review
Round, revise and learn deliberately.
State rounding and revision rules before sending. After delivery, compare actuals with the basis and classify a customer-approved change separately from rework or an untested assumption.
A sample, not a promise