How to read a window schedule

A window schedule is a structured list of window information in a drawing set. Depending on the project, it may record each physical opening or group units that share a specification. It commonly links marks, types, quantities, dimensions and notes so the project team can discuss the same items.

The table is not automatically a purchase order. It may contain design dimensions, unresolved specifications or references to another sheet. Door schedules can also include door-specific information beyond the window fields. Use the project's own instructions rather than assuming one universal layout.

The original example below uses one row per physical opening. W01 and W02 share type T01; W03 is T02. The values are teaching data, not a customer project, a measured building or the authored house demo.

Download the filled example, blank schedule and field dictionary to inspect all fields, including sources and outstanding decisions.

An opening mark identifies an item in the drawing set; a type groups a shared specification. Those roles may be combined or named differently in another project's legend. Establish the convention before counting.

In this fixture, there are three physical openings and two types. Seeing W01 again on an elevation does not add another window. Conversely, two different marks that share T01 still represent two physical units. A grouped schedule could instead show one T01 row with quantity two.

1. Locate the mark on the plan, then find the matching elevation and schedule record.
2. Confirm the building part, level and wall. Similar-looking windows on different elevations may be separate units.
3. Check whether quantities belong to individual marks or grouped types.
4. Keep an unmatched mark or schedule row on a review list instead of inventing a location or quietly adding it twice.

Identify the dimension basis before using a width and height. A structural opening, an outer frame dimension, visible glass and the clear opening of an operable unit describe different things. The relationship depends on the product and installation.

Andersen's manufacturer glossary distinguishes the rough opening in the wall from the unit and from clear opening area. Its sizing resources provide product-specific dimensions. These are references for the distinction, not a universal clearance rule for every supplier.

In our example, W01 and W02 are labeled rough-opening dimensions. W03 has numbers but no confirmed basis. Its 900 x 1500 mm therefore remains incomplete information. Do not convert that row into an order size until the responsible designer or supplier resolves the basis.

Check the drawing notes, schedule header, details and relevant product instructions. If the source gives conflicting meanings, record the disagreement and the person responsible for resolving it. Do not add or subtract a generic installation allowance.

A dimension should travel with its units. US drawings may use feet, inches and fractions; a product file may use millimeters. 6 ft 2.5 in equals 1892.3 mm. Display rounding should not change the underlying value.

A compact size code is not always a literal frame dimension. Check the source manufacturer's notation. In the Fenestry workspace, the display can use imperial or metric units while the preliminary takeoff includes explicit millimeters and a dimension-meaning field.

Operation is a separate decision from size. Fixed glazing, a tilt-and-turn window and a sliding assembly do not perform the same task just because their outer rectangles match. Use the legend and product references to interpret the operation. For handing, record whether the drawing is viewed from inside or outside and follow the supplier's convention.

Unknown operation should remain unknown. In an AI-derived model, a fixed-glass visual placeholder does not confirm that the source opening is fixed. Confirming ventilation, safe use or code compliance requires the actual product and applicable project review; nominal geometry alone cannot do that.

First confirm that you are comparing the intended revisions. Then record each source and the precise disagreement. A visible mismatch is a question to resolve, not permission to silently choose the more convenient value.

For an AI-assisted takeoff, apply the same discipline to model proposals. Check which pages were analyzed, whether the opening has a plausible host, and whether the dimensions are written, inferred or still unresolved. A successful import does not prove completeness.

Send a clear opening list with source drawings, revision references, dimension units and size bases. Include intended operation and appearance, then separate confirmed choices from questions. Give each unresolved decision an owner or a next action.

The window schedule template includes fields for source, revision, review status and unresolved items. Its worked example deliberately leaves information unknown so the missing decisions stay visible. It is a planning aid, not a fabrication specification.

If you want to connect the opening list to an editable house, explore the PDF-to-takeoff workflow. Fenestry can help organize a preliminary model and export, while product compatibility, complete quantities, installation and manufacturing still need review.

Reference basis: the source drawings and project legend control their own marks and conventions. Manufacturer terminology and sizing references are linked in the dimension section. The diagrams and CSV fixture on this page are original teaching material.