Takeoff Software for
Solar & PV Construction

Counting the array

Module count is the foundation of every solar bid. Every other line item — racking hardware, mounting clamps, conductor lengths — flows from how many panels are on the roof or in the field. On a large commercial rooftop or a multi-megawatt ground-mount project, hand-counting modules across dozens of rows is both slow and error-prone. AI takeoff auto-counts repeating panel layouts directly from the PV plan drawing, handling irregular row lengths and setback cutouts without special configuration.

Once confirmed, racking, clamps, and rails scale from that count and the row geometry in the structural drawings. The single-line diagram is the cross-check: string groupings and combiner totals should reconcile back to the module layout. Running both documents through the same session surfaces discrepancies before they become a bid error.

• AI auto-counts repeating panel rows, including partial rows at setback edges
• Racking and hardware scale from module count and row spacing
• Verify final count against the single-line diagram string totals

DC and AC wiring

Wiring footage is where solar bids frequently go wrong. The calculation is straightforward — conduit footage plus termination allowances, multiplied by conductors per circuit — but allowances compound fast on a system with many strings. Standard practice is 2–3 feet of extra conductor at each panel connection and 6–12 inches at combiner and disconnect terminations. Miss those allowances on a 500-module system and you can be hundreds of feet short before the job starts.

String runs, combiner homerun cables, and AC output circuits each need to be measured by run length from the layout. Homerun lengths vary significantly depending on where combiners land relative to the inverter pad, and a single long homerun on a ground-mount site can represent more copper than an entire residential install. Copper wire prices rose 14–17% in early 2025, so a footage error on the long conductor runs typical of solar can materially swing the bid.

• Measure string, combiner, and homerun runs by length from the layout drawing
• Add 2–3 ft per panel connection and 6–12 in per device termination
• Multiply total conduit footage by conductors per circuit for wire quantity

Conduit, inverters, and equipment

Conduit takeoff follows standard electrical practice — measure each run by size and type, count fittings, account for vertical offsets at equipment pads — but at a scale that is unusual in building electrical work. Ground-mount sites can have hundreds of metres of underground conduit in a single homerun trench. The conduit schedule needs to be broken out by size because fill requirements differ between string-level DC wiring and the larger AC output conductors.

Inverters, combiner boxes, disconnects, and step-up transformers are counted from the single-line diagram, not the module layout. The single-line shows the electrical architecture: how many inverters are in the design, whether the topology uses central or string inverters, and where the point of interconnection sits. Using the module layout to count equipment is a common source of missing line items on designs with non-obvious topology. Ground-mount projects also add pile or pier foundation counts that rooftop work does not, and those quantities need to flow into the civil scope.

Rooftop vs. ground-mount

Both project types start with the same module-count engine, but the scope around it differs substantially. Rooftop solar requires ballast counts or penetrating attachment counts depending on roof type, plus roof penetration sealing and — in most jurisdictions — fire-code pathway cutouts that reduce usable roof area and affect the final module count. Read those cutouts from the permit drawings rather than assuming from raw roof area.

Ground-mount replaces attachment hardware with structural foundations: driven pile, helical pile, or concrete pier designs each have different quantity structures. Beyond foundations, ground-mount adds trenching length for underground conduit connecting combiner boxes to the inverter pad — runs typically far longer than anything on a commercial rooftop. DC wire runs share the same trench corridors, so measuring trench once and applying it to both conduit and wire quantities keeps the takeoff consistent.

Per-trade pricing for EPCs

PILARS is priced at $100 per trade per plan with no per-seat fees. For a solar EPC, most projects touch at least two trades: electrical (modules, wiring, conduit, inverters, protection devices) and structural or civil (racking, foundations, trenching). A rooftop commercial system runs $200 for the full takeoff; a ground-mount project with civil scope included runs $300.

No per-seat fees means the estimating team shares one set of numbers without additional user charges. For a lean EPC team where the electrical and civil estimators both need access, that structure is meaningfully different from per-seat tools that charge for every person who opens the file.

• $100 per trade per plan — electrical, structural, and civil each count as one trade
• No per-seat fees: the whole estimating team shares the output
• Most solar projects settle at two or three trades per plan

Questions estimators actually ask