I am remodeling and need to expand a existing circuit. I have a 4 way switch and two 3 way's controlling one light. I need to add another switch on the same circuit to operate from a different location. I assume that I will need to exchange the last installed 3-way for a 4-way to operate the additional 3-way. Am I on track or is there something that I am missing?
You'd add another 4 way between one of the three ways and the existing 4 way.
Any advice given here is general in nature and is not necessarily valid for your given area. If in doubt check with your local codes enforcement department for what is required when doing electrical, plumbing or structural work on your house. Permits may or may not be required in your area and home owners may not be able to DIY some tasks. I have no way of knowing if you have the skills needed to complete the tasks you are asking about, when in doubt seek professional assistance.
My advice may be worth exactly what you pay me for it. :-) For the record I did not stay in a Holiday Inn Express last night.
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