Retrofitting an existing Leviton PLC system with a Homeworks RF solution. Everything is fine, except that there are 2 locations where there is a double pole, double throw switch to control 120V shades. These are in the same gang box where we are installing the homeworks dimmers, in a designer color of course. Lutron does not make a double pole, double throw switch in this designer color. I have a feeling I could use a relay of some sort, but couldn't a 3 way switch be used as well?

Thanks in advance.

A pair of switches could electrically be the equivalent of DPDT but three way is more like a SPDT.

Does a DPDT control a single shade, or are they using one pole to control each shade simultaneously?

Assuming no extra room in the j-box, maybe a relay is the best bet.

The way I understand it, there are 3 wires going from the switch to the shade. One is hot. The other 2 wires are up and down, so when the switch is in the up position, the hot and up wire is used. When in the down position, the hot and down wire are used. No room in the box for a relay, but I guess one coudl be cut in up by the shade.

Well, that is not a DPDT, that is a SPDT. 3 way switch would move it, but keep in mind you will be ALWAYS running the up or ALWAYS running the down direction. You need a momentary contact switch, not a toggling always on switch.

Lutron has some electronic shade controls I think. Google Sivoia.

Given what you have described I could envision a scenario where you might use a 4-way switch (a special version of a DPDT switch with only 4 terminals) in one location, and a SPDT (three way) switch in the other location to make this work.
As Tom pointed out there is then the issue of an off position or momentary switches?

The shade has up and down stops, so a maintained switch is fine.

If the original control kept current flowing and relied on the stops, then OK. If the original control was a momentary switch, then you are putting all your faith in the stop switches plus associated physical (plastic) actuators and may start a fire if that motor keeps running when the stop switch bites the dust.

I wouldn't...