How to Estimate Cable Footage from a Floor Plan

Most contractors estimate cable one of two ways: pace it off on the walk, or guess by eye after the fact. Both are slow, both are wrong, and both leave you holding the bag when the install crew runs short.

FieldMarkup's measurement tools take a different path. You calibrate the floor plan once (about 15 seconds), then every cable run you draw shows real footage at the cursor. When you're done, the BOM has a cable schedule with total feet per type and per-run details. Estimating cable goes from a half-hour-of-tape-measure problem to a few minutes of tapping.

Open the floor plan in the editor. In the toolbar, pick the Calibrate tool (ruler icon).

Find something on the plan whose real-world length you already know. Good options:

• A standard door (36 inches wide)
• A dimensioned hallway segment
• A parking-stall stripe (most are 9 feet wide)
• A scale bar in the title block
• Anything you can measure on-site with reasonable confidence

Tap once at one end of that feature, tap again at the other end, then enter the real distance in the dialog (with ft or m units). Hit Save. The calibration line stays visible on the plan with your entered distance as a label.

You only need one calibration per plan. If you ever need to nudge the calibration line for perfect alignment, just drag the endpoints.

Pick the Wire run tool in the toolbar. Tap at the starting device, then tap each waypoint along the cable path (around obstacles, through corners, into the IDF). The editor shows the running total at the cursor as you go.

To finish a run:

• iPad or touch device: tap the Done button in the floating banner at the bottom of the canvas. The banner shows your live waypoint count, with Done and Cancel buttons sized for fingers.
• Desktop with mouse: same Done button works, or double-click the canvas, or press Enter.
• Mid-run cleanup: backspace to pop the last waypoint, Esc or Cancel to drop the whole run.

The default cable type is CAT6. Use the contextual toolbar to switch to fiber, coax, speaker pair, alarm wire, line voltage, or pick Other for anything custom. Each type renders in a different color on the plan so different cable types are visually distinct.

Walked the building and realized one of your routes goes through a wall? Select the run with the Select tool. Three kinds of handles appear:

• Solid amber squares at each vertex: drag to move that vertex. The distance updates live.
• Hollow amber circles at each segment midpoint: drag to splice a new bend into the run at that point.
• Small red × above each vertex: removes that vertex (only available when the run has at least 3 vertices).

The pattern is borrowed from CAD tools. If you've used Maps Ruler Pro or similar, it'll feel natural.

Every wire run flows into the BOM in two places:

• Cable Schedule by Type: total feet of each cable type across the project. "CAT6: 2,847 ft. Fiber multi-mode: 318 ft. RG6 coax: 612 ft."
• Cable Schedule (Detail): per-run line items with name, cable type, and length. Useful when the estimator wants to scope materials per pull, not just per type.

Both sections show on the internal BOM PDF and the customer-facing PDF (your call which one you send). They also export to the CSV the estimator can drop straight into their spreadsheet.

• Calibrate against a long reference: longer baseline = less error. A 30-foot hallway gives a better calibration than a 3-foot door.
• Add ~10% slack to your estimates: real cable pulls deal with bends, drops, terminations, and "I need to extend this another 4 feet at the IDF." Don't commit to a tape-measure-accurate number to the customer when reality has tolerance.
• Name your runs as you go: select the run after placing it and use the contextual toolbar to name it (e.g. "C1 to NVR" or "Door 4 reader"). The cable schedule reads better with names than with the default "Wire run 1, Wire run 2."
• Don't be afraid to re-calibrate: if you find a better reference mid-job, recalibrate. Existing runs keep the distances they were drawn with, only new runs use the updated scale.