SketchUp Surface Area Calculation: 5 Areas a Takeoff Can Mean

There is no single “surface area” in a SketchUp quantity takeoff. The same wall panel can be 10 m² (one face), 22.6 m² (every face of the solid), 20 m² (its two plastered faces) or a plan area, depending on what the line item is priced on. SketchUp reads a face or a material natively; an object total, a plan area or a cut area takes a few extra steps or an extension. This post separates five areas, shows how to read each in SketchUp, then explains how SheetUp measures the two that suit an estimate row, surface area and material area, and what it leaves out.

Five areas a takeoff can mean

Area	Question it answers	Native in SketchUp	In SheetUp
Face area	How large is this one surface?	Entity Info with a face selected	Building block of the next two, no row of its own
Total surface area	How much skin does this object have?	Area command on a selection	Component row or Tag row, Per = Area (m²)
Material area	How much is finished with material X?	Area > Material in the Materials panel	Material row, Per = Area (m²)
Projected or plan area	How much ground or board does this cover?	Read a footprint face you draw or trace	Not measured; type it into a Custom row
Cut area	How large is a section slice?	Section plane, a face in the slice, Entity Info	Not measured

Face area: one surface at a time

Select a face and open Entity Info. SketchUp’s help states that the panel displays a relevant measurement for the selected entity, and Model Info lets you set the Area unit separately from Length and Volume. Three limits come from SketchUp’s own community answers:

• A group is not a face. Select a group and Entity Info shows no area; open the group and select faces inside it (DaveR, Jan 2025).
• Faces only. A selection made of faces gives a combined area; a mixed selection shows only an entity count such as “17 Entities” (AK_SAM, Oct 2025).
• Scale. In the Ruby API, Face#area returns the unscaled area of a face inside a scaled group unless you pass the group’s transformation. Any tool that totals areas has to apply the transform; SheetUp does.

A face with an opening cut through it is one face with a hole. SketchUp’s 2025.0 release notes list a fix for an Entity Info face area that was wrong when a glued component cut a hole in the face, so the reported area is that of the face that remains.

Total surface area of an object

For the skin of an object, the native route is the Area item in the context menu of a face, which calculates the total surface area of a Selection, specific Tags in the selection, or applied Materials in the selection. SketchUp’s pages do not say whether it counts one side of each face or both. Check your version once with a closed 1 m cube: 6 m² means one side per face, 12 m² means both.

Extensions fill the gaps. FredoTools’ Report on Areas (plugin thread) works on a selection, lets you choose the unit and decimals, and, per a user comparison, exports CSV (IanT, May 2019). TIG’s Component Reporter ++ exports material area per component to CSV (same thread).

Material area: painted or finished surfaces

Context-click a material in the Materials panel and choose Area > Material: an Area dialog box shows the total area of faces to which the selected material is applied. If the item is grey, the material is on no face. Two things to know before trusting the number:

• Containers. Unpainted faces take the material of the group or component that holds them. Users report that material area then counts both sides of each face: a 1 m cube group painted from outside gave 12 m², not 6 m² (Geo, Oct 2014; IanT, May 2019). Both threads are old, so repeat the cube test in your version.
• One material at a time. A 2018 to 2025 thread on getting areas by material for a selection ends with users recommending extensions rather than Generate Report (SketchUp Community). Eneroth’s Material Area Counter (source) counts the whole model; a user found it counted front and back faces.

For turning material areas into purchase quantities, see how to calculate material quantities in SketchUp.

Projected or plan area

Plan area is the outline seen from above, such as what a roof covers on the ground, not the sum of the faces. In SketchUp you normally read it from a face of the outline, drawn or traced, in Entity Info. I did not find a native command that projects a model onto a plane and reports the area. The difference matters: a gable roof 10 m long and 6 m wide in plan, rising 1.5 m at the ridge, covers 10 × 6 = 60 m² of plan but has two slopes of 10 × √(3² + 1.5²) = 10 × 3.354 = 33.54 m² each, 67.08 m² of roof surface. SheetUp measures the second figure, not the first: to price by plan area, read the footprint face and type the figure into a Custom row, where the name, quantity, unit label and price are yours and the quantity is never converted.

Cut area from a section

A section plane’s fill is a style setting; SketchUp’s help says a filled cut needs geometry in the section slice that forms a closed loop. To measure a cut you need real geometry: Create Group from Slice produces grouped geometry where the plane meets the model, but the help page does not say whether it contains faces. A forum reply says it creates lines and that you draw over an edge to fill the surface (SketchUcation); TIG’s Section Cut Face extension is mentioned for the faced version (SketchUp Community, Apr 2024). Once the slice has a face, Entity Info gives its area; SheetUp does not measure cut areas.

How SheetUp measures area

SheetUp is our quantity takeoff extension (bill of quantities, BoQ, in UK usage). Its estimate is one table of rows that you add by hand: there is no Generate step and no automatic listing of the model. A row points at a Custom item, a Component, a Material or a Tag, and SheetUp measures only what the rows point at. The Code prefix says which kind a row is: CMP- component, MAT- material, TAG- tag, CUS- custom. Areas are computed in metric and converted for display and export.

Adding an area row

1. Press Add row in the bar at the bottom of the window. One popover opens with Custom row, Component…, Material…, Tag… and, when objects are selected in SketchUp, From selection. The three lists are searchable and have checkboxes: clicking a row only ticks it, Select all results ticks the filtered list, and Add N selected adds the ticked entries in one step. From selection adds one Component row per distinct component selected.
2. In the Per column pick Area (m²), or Area (ft²) in imperial, from the dropdown. A new Component or Tag row starts on Each, a count, and a Material row on Area, so for an area price on a component or a tag you change Per yourself. Do it before typing the price: changing Per keeps the number in the Price cell and reads it per the new unit.
3. Type the price per area unit. Leave Factor at 1 or use it as a multiplier (two coats: 2), and set Waste % and Tax % where needed; a blank Waste % or Tax % takes the default from Settings.
4. Read Total: Qty × Factor × Price × (1 + Waste/100) × (1 + Tax/100). The grand total is the last row of the table. Whatever Per is, the Area column shows the measured area of every model row, so you can read a surface area without pricing it. The Columns button in the top bar shows or hides columns; hidden columns are still exported.

The Name cell of a model row is not just a label: editing it renames the real component, tag or material in the SketchUp model, in one undo step, and the row follows. Quantities re-measure automatically a moment after the model changes.

Component row: the component as a whole

A component is any named group or component instance that holds faces of its own or nested instances. A Component row measures it as a whole: for each instance, its own faces plus everything nested inside it, rolled up through the instance transforms, times the number of instances. Each face counts once, one side. The host sends the area per face normal and SheetUp maps each one through the placed transformation, so the result is exact under uniform and non-uniform scaling, rotation and mirroring. Instances with the same tag and name are one component and are summed.

A container with no faces of its own, such as a window group holding glazing, sill and head, measures as the sum of its parts: 14 windows of 1.7 m² of parts each give 23.8 m². The Count and W × H × L columns give the number of instances and the sorted extents of the component’s bounds (Width the smallest, Height the middle, Length the largest, so Height is not the Z axis).

SheetUp takes each face’s area from SketchUp (Face#area), so a face with an opening cut through it contributes what SketchUp reports for it. SheetUp has no hole-deduction feature; it adds the faces as modelled. A window placed in front of an uncut wall deducts nothing, while an opening cut into the wall has already left the wall’s faces.

Tag row: one sum, nothing counted twice

A Tag row is the sum of the own (direct) geometry of every component on the tag. A part nested inside a component on the same tag is counted once, as its own component, never again inside its container.

Double counting across rows stays your choice: a Component row and a row for one of its parts both count that part, and nothing is deducted from the parent. The Code prefix shows what each row points at.

Material row: area per finish

A Material row is one material. Its quantity is the area of every face painted with it (Per Area) or the number of those faces (Per Each). A face counts once, with its front material or, if it has none, its back material. A face with no material takes the material of the nearest painted ancestor group or component instance; with no painted ancestor it is in no Material row, only in the Component or Tag row that holds it. When an instance is scaled non-uniformly, its material areas are scaled by one overall ratio, so the total is exact and the split between materials is proportional.

A Material row cannot be narrowed to a few components, because its area needs every face of the model. SheetUp’s own benchmark records 17.4 s to measure every one of the 10,038 root groups of a large test model; I did not time a Material row on it.

Selection, units and export

Selecting objects in SketchUp highlights the rows whose component or tag matches; there is no separate panel or selection total. From selection in the Add row popover starts from the same selection.

A Metric / Imperial switch in Settings sets the display units, m² or ft² for area. Prices are typed per display unit and stored per metric unit, so totals do not change with the switch: 1 ft² = 0.09290304 m², so 10 m² shows as 107.64 ft².

The Export menu offers Excel (.xlsx), HTML report, CSV, Copy to clipboard and Print, and Import lines reads an exported file back. The XLSX is one flat sheet named Estimate with one record for each row of the table and 20 columns: Code, Name, Source type, Tag, Count, Width, Height, Length, Total length, Area, Volume, Weight, Qty, Per, Factor, Price, Waste %, Tax %, Total and Density. Per carries the dropdown label, for example “Area (m²)”. The row Total and the totals block (Lines, Lines priced, Subtotal, Waste, Tax, Total) are live Excel formulas with cached values. SheetUp does not group: sum areas by tag or material with a pivot table, and filter on Source type first, because a Component row and a Tag row over the same geometry count it twice. Excel, CSV and HTML exports go through a license gate (a sign-in and a free allowance); Copy, Print and Import do not. Cost arithmetic is in the cost estimate post.

Worked example: one wall panel

A group “Wall Panel” on the tag Walls, a closed box 4 × 2.5 × 0.2 m, painted Concrete as a group, with its two large faces painted Plaster. Faces and arithmetic:

• Face area, one large face: 4 × 2.5 = 10 m².
• Edge faces: top and bottom 2 × (4 × 0.2) = 1.6 m²; the two ends 2 × (2.5 × 0.2) = 1.0 m²; together 2.6 m².
• Surface area: 2 × 10 + 2.6 = 22.6 m². Check with 2(ab + bc + ca) = 2(10 + 0.8 + 0.5) = 22.6 m².

In SheetUp, Add row > Component… with Wall Panel ticked, then Add row > Material… with Plaster and Concrete ticked, give these rows:

• Component row CMP-WALL-PANEL-01: Per starts on Each, so Qty is 1 (Count 1). The Area column already reads 22.60 m², Volume 2.00 m³ and W × H × L 0.20 × 2.50 × 4.00 m. Set Per to Area (m²) and Qty becomes 22.60 m².
• Material row MAT-PLASTER-01 (Per Area by default): Count 2 (faces), Qty 20.00 m². Material row MAT-CONCRETE-01: Count 4, Qty 2.60 m² (the four unpainted edge faces take the group’s material), when this panel is the only Concrete in the model. The two rows add to 22.60 m².
• Pricing the plaster: Per Area (m²), Qty 20.00, Factor 2 for two coats, Price 18.50 per m² (an illustrative rate), Waste % 5, Tax % blank with the Settings default at 0. Total = 20 × 2 × 18.50 × 1.05 = 777.00, which is 740.00 plus 37.00 of waste. With this the only priced row, the last row of the table also reads 777.00. The app shows no subtotal or waste breakdown; the XLSX totals block does.

The same panel built as a component 2 × 1.25 × 0.1 m and placed at scale 2 has a definition area of 2(2.5 + 0.2 + 0.125) = 5.65 m²; area grows with the square of the scale, 5.65 × 4 = 22.6 m².

Now cut a 1.0 × 1.5 m window through the panel and assume the four reveal faces are unpainted. Each large face is 10 − 1.5 = 8.5 m²; the reveal is 2 × (1.0 + 1.5) × 0.2 = 1.0 m². The Component row (Per Area) becomes 2 × 8.5 + 2.6 + 1.0 = 20.6 m²; Plaster is 17.0 m² and Concrete 3.6 m² (again 20.6). A window component placed in the opening gets its own row; nothing is deducted for it. For the volume of the same panel, 4 × 2.5 × 0.2 = 2.0 m³, see how SheetUp measures volume.

Which area for which row

Item priced	Row to add	Watch for
Paint, plaster or cladding by finish	Material row, Per Area (m²)	Faces must be painted, or inherit from a painted container
A wrap, membrane or coating on whole objects	Component row, Per Area (m²)	A new row starts on Each: change Per to Area
Everything on one tag	Tag row, Per Area (m²)	Own geometry only; parts are counted once; Per starts on Each
Plan area: roof on the ground, slab footprint	Custom row	Read the footprint face yourself; type the quantity, a unit label such as m² and the price

What I could not check

• Whether Area > Selection counts one side or both sides of each face: SketchUp’s help does not say; the cube test above settles it per version.
• Whether the 2014 and 2019 forum reports of doubled material area still hold in current SketchUp releases.
• Whether Create Group from Slice yields faces: the help page is silent, one undated forum post says lines.
• That Face area excludes holes is shown only indirectly, by the 2025.0 release note; no help page states it, and the 20.6 m² figure for the cut panel rests on it.
• Which material SketchUp gives the reveal faces after a cut: the example assumes they are unpainted.
• The wall panel numbers were checked by hand and by running SheetUp’s measuring and pricing code on a described model in a test harness that stands in for SketchUp, not by drawing the panel in SketchUp. The menus and column names above are read from SheetUp’s source, not from a live SketchUp session.
• How long a Material row takes on a very large model: not timed.
• The extensions named: I did not run them; their behavior is as their users report it.

Sources

• SketchUp Help: Managing Units of Measurement, opened 2026-11-09
• SketchUp Help: Entity Context Menus
• SketchUp Help: Calculating Material Area
• SketchUp Help: Creating and Using Section Planes
• SketchUp Desktop 2025.0 release notes
• SketchUp Ruby API: Sketchup::Face
• SketchUp Community: No area info after grouping, Entity Info upgrade request, Area measurements, Calculate surface area of components for paint coverage, Generate Report: areas by material, Create Group from Slice issue report
• SketchUcation: Section cut again, FredoTools::ReportLabelArea, Eneroth face area counter on GitHub

FAQ

How do I find the surface area of a group in SketchUp?
Entity Info shows no area for a selected group, because a group is not a face (SketchUp Community, Jan 2025). Open the group and select the faces inside it, use the Area command on a selection, or use an extension that reports per group. In SheetUp, use Add row, then Component…, and tick the group: its Area column shows the sum of its own faces and nested parts, one side each, at its placed scale, and Per = Area (m²) prices the row on that figure.

Can SketchUp calculate the area of several faces at once?
Yes, when the selection holds faces only: forum answers report that the combined area then appears in Entity Info (thread). With a mixed selection Entity Info shows only an entity count such as “17 Entities” (feature request, Oct 2025). Painting the faces with one material and using Area > Material totals them across the model, groups included.

How do I calculate floor area in SketchUp?
Select the floor face and read the area in Entity Info; if the floor is a group, open it first. For a whole storey, read one face of the outline (the footprint). That is a plan area, not the surface area of the slab, which also includes its underside and edges. SheetUp does not measure plan area: read the footprint face and type the figure into a Custom row.

Why is the material area twice what I expected?
Because both sides of every face are counted when the material is applied to a group or component. Painting a 1 m cube group reported 12 m² instead of 6 m² in two forum tests (2014, 2019), and a face painted on both sides counts twice. Paint only the front faces, or halve the figure; test your version with a 1 m cube first. SheetUp’s Material row counts each face once, one side.