3-way for stairs.

[Lettherebelight110]

Just took my electrical license exam for ohio. one of questions was, how many steps on a stairway before you must have a 3-way switch at the top and bottom. can some one give me a code reference for this?

 

[John120/240]

Three way switches are not required by the NEC, however it is a common practice to use three ways to control one light fixture. You could have a single pole switch at each level, each switch controlling a light on its level & be NEC compliant. Six or more stair treads is the threshold. for this requirement. Others will chime in hopefully

 

[Lettherebelight110]

on the test the options were

a.)1
b.)2
3.)3
4.)4

 

[John120/240]

on the test the options were

a.)1
b.)2
3.)3
4.)4

Damn test writers. 210.70(a)(2)(c) I believe the code states six risers or more

 

[GoldDigger]

The numbers on the test must be double steps (R,L).
That makes the correct answer 3.

 

[fmtjfw]

210.70 Lighting Outlets Required.
(A) Dwelling Units.
....
(2) Additional Locations. Additional lighting outlets shall be installed in accordance with (A)(2)(a), (A)(2)(b), and (A)(2)(c).

(a) At least one wall switch?controlled lighting outlet shall be installed in hallways, stairways, attached garages, and detached garages with electric power.
....
(c) Where one or more lighting outlet(s) are installed for interior stairways, there shall be a wall switch at each floor level, and landing level that includes an entryway, to control the lighting outlet(s) where the stairway between floor levels has six risers or more.

Exception to (A)(2)(a), (A)(2)(b), and (A)(2)(c): In hallways, in stairways, and at outdoor entrances, remote, central, or automatic control of lighting shall be permitted.

From 210.70(A)(2)(a) I get that any stairway (1 to n risers) requires a switch.
From 210.70(A)(2)(c) I get that a stairway with 6 or more risers requires two or more switches.
From the exception I get that no switch is required. I would ignore the exception as it specifies no riser count.

I would have answered 4 and contested the question, the grounds being the correct answer is 6 and not supplied. I would further note in the contest that, although the3-way switch are not specified in the code, only a code lawyer would claim they are not what should be installed.

 

[infinity]

Although no 3-ways are required I would have chosen 2. When using 3-way switches you only use two 3-way switches.

 

[John120/240]

Although no 3-wyas are required I would have chosen 2. When using 3-way switches you only use two 3-way switches.

I thought we were talking about the number of stair risers, not the number of switches involved

 

[infinity]

I thought we were talking about the number of stair risers, not the number of switches involved

We are but 6 wasn't one of the answers.

 

[elf friend]

I believe here in Wi that the state code, com16, states that anytime there are four or more stairs three way switching is required. I know I always have put them that way and my house, which is 75 years old was wired that way.