Revit schedules against AiN quantities: the proof sheets
Revit schedules are what a client or a modeller usually holds up against a bill of quantities, so AiN Engine, the BOQ software I develop and work with, has proof sheets that set its quantities against them. The sheets put the quantity export and the material export from Revit, a manual BOQ and the architect's schedules next to AiN's numbers, so a gap shows on screen and can be explained. This page covers what is in each sheet, how to use them and what they do not do.
What you see in the proof sheets
- Revit quantities · Revit materials · Manual BOQ: three source tabs. For each model, the quantity export from Revit, the material export from Revit and the manual BOQ, each set against AiN's numbers, with a fixed gap threshold that decides what counts as a match. This sheet is read-only.
- Proofs: a table of reference projects shown by letter only, project A, project B and so on, with whether AiN's export reproduces each project's reference totals within the threshold.
- Finishes proofs: the finish elements in the loaded model against the totals of the run, per project letter. It relies on finish elements created with AiN's tools for Revit, so on a model without them it has nothing to compare.
- Architect Schedules: the architect's own schedules, loaded from an Excel file and shown next to the model quantities. The file is read in the browser only.
- DesignBuilder import: a tab that imports an energy model file (gbXML) and shows its geometry data in a table next to the BOQ. The import is local.
- Import from Revit: an item in the File menu of the BOQ window. Schedule data from Revit comes in as evidence, the panel lists the conflicts by type, and it says plainly that it is evidence only and changes no quantity until you approve it explicitly.
Why I check AiN against Revit schedules
A bill of quantities built from a model looks precise, so it needs proof. The client, the contractor or the modeller usually has the Revit schedules, and the first question is why a number in the BOQ differs from the number in the schedule. When the two stand side by side, the conversation moves from who is right to what the gap is and where it comes from.
A gap does not mean that one side is wrong. Revit calculates by its own rules: material takeoff volumes are approximations, openings are deducted with no minimum size, and linked models or phases can be inside a schedule or outside it. The sheet shows the gap; explaining it is a quantity surveyor's job.
What it gives you
- Three sources, not one: the same model is checked against the quantity export, the material export and a manual BOQ.
- A clear definition of a match: the comparison runs against a fixed threshold shown in the sheet, so what counts as a gap is not a matter of opinion.
- No silent changes: the import from Revit is evidence only, and a quantity in the BOQ changes only after a person approves it explicitly.
- Proof without names: the Proofs sheet shows reference projects by letter only, so it can be shown without naming a client or a project.
- The designers' sources in the same window: the architect's schedules and the energy model data sit next to the bill of quantities.
How to use the proof sheets
This is how I compare a bill of quantities with Revit schedules, step by step:
- Export the model's quantity schedule from Revit, and the material takeoff if you need it.
- In the BOQ window, open the File menu and choose the import from Revit. The data comes in as evidence only.
- Go through the conflicts by type, then through the Revit quantities, Revit materials and Manual BOQ tabs, which show the gaps for every model that has those exports.
- Write down a reason for every gap: a schedule setting, a measurement rule, an element missing from one of the sources, or an error. A value missing from a source is missing, not zero.
- Approve a change to the BOQ only when the reason is clear. Everything else stays as it is.
What the proof sheets do not do
Before you start: the sheets do not produce Revit schedules for you. Without the model's exports or a manual BOQ for it, there is nothing to compare. The sources sheet is read-only, and no sheet decides who is right: the explanation of each gap, and the decision, belong to a person. The finishes proofs apply only to a model that has finish elements created with AiN's tools for Revit.
Frequently asked questions
Does AiN change its quantities to match Revit schedules?
No. The import from Revit is evidence only, and the panel says so. A quantity in the BOQ changes only after a person approves it explicitly.
What do I need for the comparison?
The Revit exports of the same model, a quantity schedule and a material takeoff, or a manual BOQ for that model. For the Architect Schedules sheet, you need the architect's Excel file.
Why are the projects in the Proofs sheet shown as letters?
Because client and project names are not published. A letter is enough to see that the export reproduces the reference totals, without revealing whose project it is.
The gap is small. Why not ignore it?
Because a small gap on one line can point to something systematic: a schedule setting, a phase, or a linked model that was left out. Once you understand the reason, you know what to check in the rest of the BOQ.
The proof sheets are one part of the software. All the windows are on the BOQ software page, how every quantity carries its source is on the quantity audit trail page, clash detection and the checks before a BOQ goes out are on the quality control page, and the takeoff by category, type and level is on the Revit quantity takeoff page. For the other side of my work, see Yaakov Avital, quantity surveyor.
Want to see AiN on your own model? The AiN Engine site has the demo video, the pilot for one project and the login. For quantity surveying work in Israel, write to me through the form.
AiN Engine website Contact form* Created with AI for marketing, for illustration only. Not reviewed by Yaakov Avital and not professional advice. Every project must be checked on its own by a professional quantity surveyor and an engineer.