# Estimating Electrical Labor Units

When estimating projects labor is input as labor units. Therefore, it is essential to understand the use of labor units. So, what is a labor unit? It is a simple formula.

1 Man/Hour = 1 electrician working for 1 hour.

AND

1 Man Hour = 1 Labor Unit

So, the amount of time it takes to install electrical materials is measured in Labor Units. A Labor Unit is equal to one man hour. The Labor Unit breaks down labor into 100ths of an hour to make estimates more precise.

Electrical estimating software Labor Unit breakdown

If 1.00 labor units = 1 hour

THEN

.05 labor units = 3 minutes
.10 labor units = 6 minutes
.20 labor units = 12 minutes
.25 labor units = 15 minutes
.50 labor units = 30 minutes
.75 labor units = 45 minutes  Related Concepts when using electrical estimating software

What is a Unit of Measure (UOM)?

E = One or per each item.

C = Per 100 items (C is the Roman Numeral for 100)

M = Per 1000 linear feet of an item (M is the Roman Numeral for 1000)

Notes - The C (per hundred) Unit of Measure is typically used for installing conduit. The M (per thousand) Unit of Measure is typically used for installing wire and cable.

Calculating Labor Hours and UOM of E (each) - “E” units of measure are typically items such as light fixtures and poles, transformers, generators, disconnect switches, switchboards, panel boards, motor control centers (MCC), compression/mechanical lugs, motor connections, terminations and Cadwelds (for grounding)

Example 1

Let’s say that it takes 1.20 hours per Each to install a certain type of light fixture. That means that it would take 1.20 hours or 1 hour and 12 minutes (.2 hours = 12 minutes) to install each light fixture. To install 10 light fixtures would be 10 X 1.2 (hours) or 12 man-hours to install 10 light fixtures.

Example 2

Let’s say that it takes 4.75 hours per Each to install a transformer. To install 2 transformers would be 4.75 hours X 2 = 9.5 man hours total.

Calculating Labor hours and UOM per C (hundred) - “C” units of measure are typically items such as conduit and fittings, some devices (like switches and plugs) and some junction boxes.

Example 1

Let’s say that it takes 4 hours per/C (hundred) to install ¾” EMT conduit. That means that if you have to install 200 feet of conduit it would take 8 man-hours. To install 1,000 feet it would take 40 man-hours.

Example 2

Let’s say that it takes 40 hours per/C (hundred) to install 20 amp 4 wire twist lock receptacles (0.4 hours per device). That means that if you need to install 10 twist lock receptacles it would take 4 man-hours. To install 15 devices it would take 6 man-hours.

Calculating Labor Hours and UOM per M (thousand) - “M” units of measure are used for cable and wire.

Example

Let’s say that it takes 6 hours per/M (thousand) to pull #10 wire size of wire. That means that if you have to install 1000 feet of wire it would take 6 man-hours. To install 1000 feet it would take 40 man-hours.

Why electrical estimating software?

Speed and accuracy! An estimating program automatically applies labor units to the material items and calculates the total material and labor costs for your installation. The estimating program saves you time by running all the calculations and conversions in a fraction of the time required to do so by hand. 