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An estimate helps everyone agree in advance on the work, materials, quantities, and project cost. For a contractor, it is a financial plan and a basis for agreement with the client. For the client, it is a clear list of expenses and a way to monitor the budget. A sound estimate answers four questions: what will be done, in what quantity, at what unit price, and for what total cost.
This guide covers the definition, main types, structure, example calculation, and checks before approving a construction estimate. A detailed sequence is available in our separate guide How to prepare an estimate (in Russian), and a quick free workflow is explained in the article about estimates in 101 WEB (in Russian).
What is an estimate?
An estimate calculates the planned cost of work, materials, and related project expenses. Each line connects a description, unit of measurement, quantity, unit price, and amount. The sum of the lines gives the expected budget based on the information currently available.
The basic line formula is simple: quantity × unit price = line cost. The total project cost adds up work, materials, delivery, equipment rental, waste removal, and other agreed expenses. A contingency allowance can be shown as a separate line with a clear rule for using it.
Why do you need an estimate?
An estimate turns a general promise to “do the renovation” into a verifiable project scope. It helps agree on price, purchasing, stages, and changes. One document reduces the risk of omitted work, double-counted materials, and disputes over what the agreement included.
- Before work starts, it helps assess the budget and compare options.
- During the project, it helps track purchases, completed quantities, and deviations.
- When changes occur, a new version shows how additional work affects the total.
- At handover, the lines connect the actual result to the agreed scope.
Compare the planned estimate with actual costs. This reveals overspending, savings, quantity errors, and the effect of changes on the contractor’s margin.
Types of estimates
The name and level of detail depend on the task, contract, and project requirements. A clear commercial estimate is often enough for a private renovation. For regulated projects, the form and calculation method follow the rules of the relevant jurisdiction; the practical options below do not replace those documents.
| Type | What it shows | When to use it |
|---|---|---|
| Preliminary | Approximate budget based on available inputs | Before precise measurements and a complete scope |
| Commercial | The contractor’s offer price: work, materials, and conditions | For agreement with the client |
| Working version | Current calculation after agreed changes | During project execution |
In Russian regulatory practice, local, object-level, and consolidated estimate calculations are used. A consolidated calculation may cover one asset, a stage, or a group of assets; the applicable method determines its contents. Our article on design and estimate documentation (in Russian) explains the structure in more detail. For an ordinary contractor, the practical priority is a commercial calculation that is transparent, checkable, and easy to update.
What goes into an estimate?
A useful estimate follows the order of project execution. Start with identifying details and inputs, then sections of work, line items, and totals. Materials can sit beside the work or in a separate block; keep the link to the stage and quantity.
- Header: project, address, client, contractor, date, and version number.
- Inputs: measurements, design, list of rooms, material requirements, and site constraints.
- Sections: demolition, preparatory work, building services, finishes, and related expenses.
- Line items: description, unit, quantity, price, and amount.
- Materials: quantity, price, delivery, lifting, and an allowable reserve.
- Totals: section subtotals, overall total, discounts, markups, and contingency.
- Terms: price validity, payment process, and rules for changing quantities and approving extra work.
Line descriptions should be specific. “Wall finishing” leaves too many possibilities. “Prepare walls with filler for painting, 120 m²” identifies the work, intended result, and quantity.
What an estimate looks like: a simple example
The following is an illustrative excerpt from a commercial estimate. These Russian-ruble prices are hypothetical, not a local price guide. A real project needs current measurements, the contractor’s price list, region, and material requirements.
| Item | Unit | Quantity | Unit price | Amount |
|---|---|---|---|---|
| Prepare walls with filler for painting | m² | 120 | 550 ₽ | 66,000 ₽ |
| Paint walls in two coats | m² | 120 | 350 ₽ | 42,000 ₽ |
| Materials for preparation and painting | set | 1 | 65,000 ₽ | 65,000 ₽ |
| Delivery and lifting | service | 1 | 12,000 ₽ | 12,000 ₽ |
| Total (illustrative Russian-ruble example) | — | — | — | 185,000 ₽ |
In a complete document, group items by room or stage. Keep notes beside the calculation: material brand, price source, surface conditions, and boundaries of the work. This makes each line easier to check and update.
How to calculate an estimate
Start with the input data. Setting prices immediately often leads to omitted quantities and rework. A practical sequence is:
- Record the rooms, stages, and intended outcome.
- Measure the site and convert measurements into work quantities.
- Divide the project into sections in execution order.
- Select price-list items and verify their units.
- Multiply the quantity of each item by its unit price.
- Add materials, delivery, rental, waste removal, and other related expenses.
- Check dependent operations and consumables.
- Calculate section subtotals and the overall budget.
- Save the version and the assumptions behind the calculation.
A detailed method for preparing inputs and controlling versions is in How to prepare an estimate for renovation or construction (in Russian). A separate article shows how to use AI to prepare and insert estimate line items (in Russian). The resulting calculation still needs a check of quantities, prices, and scope.
Where can you create an estimate for free?
A small estimate can be prepared in a spreadsheet. For recurring work, it is easier to keep one price list, add items quickly, update prices in bulk, and save versions. In 101 WEB, you can create an estimate for free from a price list or manual items, link it to a project, and export it for approval.
Open the free 101 WEB estimate guide (in Russian). It covers importing a price list, adding rows, changing prices in bulk, and exporting the result.
How to check an estimate
Check it before sending it to the client and after every significant change. Work from top to bottom, then check arithmetic, completeness, and terms separately.
- Do areas, lengths, and item counts match the measurements?
- Does every line have a unit of measurement?
- Do work descriptions match the intended result?
- Are preparation and related operations included?
- Are work, materials, delivery, and equipment distinguished?
- Are line and section totals calculated correctly?
- Are contingency, markup, discounts, and VAT clear where applicable?
- Are the date, version, price validity, and change process recorded?
A longer checklist is in How to check a construction or renovation estimate (in Russian).
Common mistakes
- Vague descriptions. The line does not identify the operation and outcome.
- Incorrect units. Metres, square metres, and pieces are confused in one calculation.
- Omitted preparation. The finish is priced without priming, levelling, or demolition.
- Outdated price list. The price looks precise although its source is no longer current.
- Only one file version. After changes, the approved version cannot be reconstructed.
- Hidden related costs. Delivery, lifting, rental, and waste removal appear only after work starts.
Quick answers
Are an estimate and a budget the same thing?
A budget sets an overall spending limit or plan. An estimate breaks it down by work, materials, quantities, prices, and sections.
Can you prepare an estimate without a design?
A preliminary calculation can use measurements and a work list. Its accuracy depends on how complete those inputs are. Once the design and quantities are clarified, create a new version.
Who prepares an estimate?
In private construction, a contractor, site manager, or project manager often prepares it. For regulated projects, requirements for the estimator and method depend on the country and project terms and must be checked separately.
How often should an estimate be updated?
Create a new version when quantities, scope, prices, materials, or project terms change. Record the date and reason beside the version.
What should you do after approval?
Link items to stages, purchases, and actual costs. This helps monitor deviations and the effect of changes on the project total.
For a practical calculation, try the free online estimating tool in 101.