Convention Applied by the app elec.mount-height.defaults
Default mount heights for devices
The heights above finished floor the app starts each device at — 18" receptacles, 44" GFCI at a counter, 48" switches, 78" panel top — so the Chain tool can write the vertical.
| When | The app uses |
|---|---|
| Duplex receptacle, to center | 18 in AFF |
| GFCI receptacle at a counter | 44 in AFF |
| Single-pole switch | 48 in AFF |
| Panelboard, to the top | 78 in AFF |
| Exit sign | 90 in AFF |
| Data outlet | 18 in AFF |
| Thermostat | 48 in AFF |
- Source
- NEC · 404.8(A), 240.24(A); ADA 308 reach range · read the public text
- Editions checked
- 2020 · 2023
- Used by
- Chain tool Quick creator
- Amendments
No state or local amendment to this rule is on file. Not on file means the model code as written — check your jurisdiction.
A working figure the trade uses and the app defaults to. Shops override these most.
No code tells you a receptacle goes at 18 inches. The NEC only caps how high a switch or a breaker handle may be (6 ft 7 in), and accessibility rules bound the reach range (15 to 48 inches for an unobstructed forward reach). Inside those, the trade has working figures, and the architect's elevations or the specification override them job by job.
What the app does with it
When you create a device on the Quick tab, its mount height is prefilled from this list and rides the counter; you can overwrite it before you Add or edit it later. The Chain tool then writes ceiling height minus mount height plus make-up as the vertical on every run it draws to that device. The panel figure is to the top of the can, which is what the homerun's vertical needs.
What it does not do
It does not read heights off the drawings. A device schedule that says 42 inches wins, and the counter is where you say so.
Cited by section, not reprinted: the code text belongs to its publisher. Company practice is not a rule here — it lives with your pricing.