LoadLensCOOLING LOAD FROM PDF

Read a floor plan PDF, get the room-wise cooling load

LoadLens — the lens on your cooling load: read a floor plan PDF, see the load room by room. It reads the room names, areas and levels already written in your drawing or room schedule, then calculates the cooling load room by room and gives you TR, L/s and watts. No CAD, no spreadsheet, no sign-up.

Open the calculator See the method

Runs in your browser. Nothing is uploaded to a third party — or run npm start for faster server-side reading. Live at loadlens.net.

  • TR · L/s · per-room W
  • Editable room table
  • CSV + printable report
  • Works offline

How it works — three steps

From the drawing to a number you can put in a report, in a few minutes.

  1. Upload the floor plan PDF

    Drop one or many PDFs, a scanned sheet, or your room schedule (.csv / .tsv / .xlsx). LoadLens reads the text layer and pulls out the room name, number, level and area it finds. It works in your browser — no upload to a third party.

  2. Check the rooms it found

    Every room appears in an editable table. Fix a name, type the real area, set the orientation, tick Roof for the top floor and untick anything that is not air conditioned. Toilets, staircases and shafts are excluded for you.

  3. Read TR / L/s and export

    The summary shows total tonnes of refrigeration, supply air L/s, fresh-air L/s and ft²/TR, plus a per-room breakdown and per-level subtotals. Download the CSV or print the report to PDF.

What is in the calculator

  • Room name, area and level extraction

    Reads text-layer PDFs: room tags drawn on the plan, or a room schedule table. It also imports Excel / CSV room schedules directly, and can read a scanned sheet with the optional OCR box.

  • Editable room table

    Every value is yours to override — name, level, area, height, people, glass, walls, orientation.

  • Country / city design conditions

    Kerala, the Gulf and more, with outdoor dry bulb and wet bulb already filled in. Or type your own.

  • Per-room breakdown chart

    See exactly what makes the load: glass solar, wall, roof, people, lighting, equipment, infiltration, fresh air.

  • Per-level subtotals

    Ground / first / terrace level totals in TR and L/s, so each floor can be sized on its own.

  • CSV export

    One row per room with all inputs and results, ready for Excel or your own sheet.

  • Printable report

    A clean A4 report with design conditions, assumptions, room-wise table and the important notes.

  • Offline in the browser, or faster with Node

    Works with no server at all (GitHub Pages). Run npm start and a small Express server reads the PDF for you — same result, faster.

Who it is for

MEP / HVAC students and modellers

  • Practise a real room-wise load on a real drawing, not a textbook table.
  • See the size of each component — glass solar, people, fresh air — and how it changes.
  • Learn what the assumptions do before they go into a live project.

Consultancies in Kerala and the Gulf

  • Hot, humid design conditions (Kochi 35/28 °C, Dubai 46/29 °C) are already loaded.
  • First-pass tonnes, L/s and ft²/TR in minutes, to check a tender document.
  • CSV and a printable report for the file — then verify before it goes out.

What this tool does not do — please read

  • A scanned drawing needs help. The best input is a text-layer PDF (exported from CAD or a drafting tool) or an Excel / CSV room schedule. LoadLens can also read a scanned or image PDF with the optional OCR box, but OCR is slow and the small area labels on a scanned drawing usually cannot be read back — for a scan, import the Excel / CSV room schedule instead.
  • The load method is handbook-level. It is a simplified ASHRAE / Carrier E-20 style estimate using peak solar gain and equivalent temperature differences (ETD / CLTD), not a full hourly radiant-time-series calculation. See the method page for the exact numbers.
  • Every result must be checked by a qualified HVAC engineer. Areas, heights, glass, people and ventilation rates read from a drawing are a starting point, not a design. Duct heat gain, fan heat, diversity and the local code are not included.
  • It is for study and for checking. Do not issue a final equipment selection from these numbers without a proper check.