How to Obtain a Structured Quantity Takeoff Table from Your Plans

How to Obtain a Structured Quantity Takeoff Table from Your Plans

To obtain a structured quantity takeoff table from your plans, you need to start with the right files, ensure they are measurable, standardize your codes, and then export quantities classified by trade, level, code, and unit. Without this preparation, you often end up with a raw export that you must manually reprocess in Excel, in a DPGF, or in a cost estimating software.

Key Points

• An actionable table should already anticipate its final columns: trade, level, code, description, unit, quantity, and source.
• Before any quantity takeoff, you must check a known dimension per level and exclude uncounted areas.
• The quality of the result depends as much on the nomenclature as on the software: poor naming produces poor classification.
• The right export depends on the final use: XLS for checking, CSV for re-importing, integrated view for quick reading.

Before You Begin: Gather the Right Inputs

Files to Have on Hand

The final table is prepared before extraction. If you start with incomplete plans or unclear units, you'll end up with a quantity takeoff that's difficult to review, even with good software.

• PDF or DWG plans: keep the cleanest source version possible, including the latest modifications.
• Legible scale: ensure it is visible and consistent on every plan used.
• Trade nomenclature: align your trades with your CCTP, your DPGF, or your internal breakdown.
• List of expected units: m², ml, m³, or unit, depending on what you need to estimate.

The Final Output to Target from the Outset

An actionable table should already anticipate its final columns. I always aim for at least trade, level, code, description, unit, quantity, source, because this allows you to filter, consolidate, and justify each line.

For a partitions trade, a row might look like “CLO_D72 | GROUND FLOOR | C-12 | Partition 72/48 | m² | 18.40 | plan A-03”. For joinery, you might have “MENU_EXT | GROUND FLOOR | P-01 | Door block 90 x 215 | unit | 2 | plan A-05”.

A raw export can already calculate areas or lengths. But without structure, this results in manual reprocessing. That's where tools like constor add value, when they produce a table directly linked to the plan and sorted by work package.

Step 1: Check that the Plans Are Measurable

Check the Scale and the Levels

1. Open each plan and check at least one known dimension per level before starting the quantity takeoff.
2. Compare this dimension with the size displayed in the file to confirm that the plan is to scale.
3. Identify non-vector scanned plans, overlaid versions, and documents without a legend, as they quickly distort measurements.

Several tools can automatically calculate areas, volumes, lengths, and objects from the drawn elements. The weakness is not the calculation, but the quality of the input file.

Identify Areas to Exclude

Immediately mark what should not be included in the table: voids, shaft openings, spaces counted elsewhere, or out-of-scope areas. Without this sorting, you add up areas that do not have the same status.

Classic example: a door appears on both the architectural and technical plans. If you keep it in both extractions, you count it twice. This is not a calculation issue, but a scope issue.

Step 2: Standardize Codes Before Extraction

Naming What Will Be Counted

• Name shapes, lines, or objects systematically if your tool groups a row by name in the quantity takeoff.
• Keep a single rule to avoid the same item being classified differently depending on who processes the plan.
• Test the consistency on a small trade before applying the method to the whole file.

The best rule is simple: TRADE_SUBTRADE_ELEMENT_FORMAT. For example, CLO_D72_Corridor_GROUND FLOOR describes a trade, a subtrade, an element, and a location unambiguously. This structure remains readable in Excel and in a cost estimating software.

Choose a Single Classification Structure

The right compromise is not theoretically between “detailed” and “simple,” but between “detailed enough to be accurate” and “readable enough to be used.” If you push granularity too far, you multiply rows without real gain. If you oversimplify, you lose traceability.

The sign is simple: two different people must obtain the same categorization on the same plan. If they hesitate on the same code, your nomenclature is not stabilized.

Step 3: Extract Useful Quantities, Not All Measurements

Choose the Families to Measure

1. Measure only the families used for cost estimating or tendering: areas, perimeters, volumes, joineries, lines, and lists of objects.
2. Associate each family with a clear professional use to prevent overloaded exports.
3. Reserve other measurements for internal checks if they are not included in your DPGF or your estimate.

Units should remain standardized: m², ml, m³, units. Errors occur quickly, for example when a skirting board in m² is mixed with a partition in ml in the same row block. The result is unusable without correction.

Associate Each Quantity with Its Correct Unit

I recommend a simple mapping: partition in m², skirting board in ml, concrete in m³, door block in unit. This logic avoids late conversions and debates during cost estimating.

When possible, let the tool classify the quantities by work package and link each line to the source plan. That’s the approach targeted at constor: automatically obtain classified quantities, then use them without reentry in the study workflow.

Step 4: Build an Actionable Structured Table

The Minimum Columns

A useful quantity table does not fit into three columns. It should retain the information that lets you review, correct, and justify each line.

Recommended structure: trade, subtrade, level, code, description, unit, quantity, assumption, source page, comment.

The Preferred Excel Format

In Excel, turn the range into a structured table via Insert > Table or, as is often used, with Ctrl + L. Once it’s a table, structured references make formulas clearer, and the total row quickly secures sums, averages, or counts.

Simple example: you filter the GROUND FLOOR level, sum the partitions trade, then check for duplicate codes. The ranges automatically extend when you add a row, limiting manual adjustments.

Format	Main Use	Key Advantage	Main Limitation
XLS	Internal control, filters, totals, reprocessing in Excel	Very practical for verifying and correcting quantities	Less universal for automatic import

For a quantity table intended for review and correction, I almost always choose the XLS format first. For machine import or use in another tool, a more neutral version often needs to be prepared afterwards.

Step 5: Export in the Right Format the First Time

When to Choose XLS, CSV, or Integrated Table

• XLS: suited for reading, checking totals, and reprocessing in Excel.
• CSV: suited for importing into an ERP or estimating software.
• Integrated view: useful for quickly consulting quantities directly in the plan.

Prepare for Downstream Use

The three most common modes are adding to the plan, exporting XLS, and exporting CSV. The right choice depends on what you’ll do next. If you need to filter, sort, and add controls, use XLS. If you need to inject data into another system, use CSV.

For a tender file, CSV often avoids intermediate manipulations. For internal quantity takeoff, XLS is more comfortable. And if your goal is to avoid copy-pasting between plan and spreadsheet, aim for a table that can be directly reused by trade or for consulting.

Step 6: Check Reliability Before Estimating

The 5 Minimum Verifications

• Unit: each line has the correct professional unit.
• Duplicates: no code appears twice without reason.
• Missing elements: expected doors, partitions, or linears are present.
• Inconsistent total: the trade total remains plausible compared to the project.
• Source page: each quantity refers to its origin plan.

Field–Office Cross-Checking

A quantity isn’t trustworthy because it “comes out” of the software, but because you can explain its origin and calculation logic. Serious solutions focus on the link between quantity, source plan, and calculation rationale.

Useful example: a partition area that is very low compared to the floor area should alert you. Either the scope is incomplete, some rows disappeared, or codes were misclassified. Do not launch a DPGF or tender until the assumptions are validated.

Common Pitfalls and Quick Troubleshooting

Why the Table Is Poorly Classified

1. If the nomenclature is inconsistent, go back to object naming before touching the export.
2. If the units are mixed, separate the families before any consolidation.
3. If floors are merged, correct the level in the source plan or the sorting rule.
4. If rows are unnamed, rename them so the software correctly groups the quantities.
5. If the export lacks headers, clean the file before passing it on.

What to Do if Quantities Seem Wrong

The first reaction is simple: redo the plan preparation, then correct the codes, then clean up the exported file. In intermediate cases, the table must be reworked in Excel with filters, named ranges, or a pivot table to produce a reliable summary.

The right order is important. If the plan is poor, Excel will save nothing. If the plan is good but the export is messy, cleaning is often enough. That's when the time saved becomes tangible: less reentry, fewer quantity takeoff errors, and much better traceability.

Frequently Asked Questions

Can you get a structured quantity table from a simple PDF?

Yes, if the PDF is legible, to scale, and clean enough to measure. However, a scanned or non-vector PDF often produces less reliable results and demands more manual checking.

What columns should a quantity table have to be reusable?

The most useful columns are trade, subtrade, level, code, description, unit, quantity, assumption, source page, and comment. With this structure, you can filter, consolidate, and reuse the table in a DPGF or an estimate without losing the trace of each line.

How can I avoid duplicates between several plans of the same project?

Assign a unique code to each element and check which plan it belongs to before export. If an object appears on several plans, decide from the outset which document is authoritative for the quantity takeoff.

Is it better to export in CSV or Excel for a quantity takeoff?

For internal checking, Excel remains most practical. For importing into other software, CSV is often simpler and more stable.

How can I automatically update the table if the plans change?

The source plan, codes, and table structure must remain consistent from one version to another. If the quantity takeoff software maintains links to the source plan, updating is much faster than manual reprocessing.

For Faster Processing on Future Projects

The best method is not to just “get quantities out”, but to prepare a table already designed to be reviewed, filtered, and used. If you often handle the same trades, standardize your columns, codes, and units once and for all. This is what most reduces corrections during cost estimating, especially when plans change mid-project.