You can buy reproduction pushbutton switches that meet all current codes.

Here is a link that might be useful: reproduction pushbutton switch

But I don't want to buy new ones if I can refurbish the old....not just for the cost savings but because I strongly believe in reusing historic materials whenever it's feasible. The K&T wiring isn't suited to modern appliances, so it has to go, but if the switches can be redone I'd like to continue using them.

Check with your local electrical inspector (Authority Having Jurisdiction or AHJ). You might be able to run a pigtail from the metal frame of the switch to the circuit ground (and the box if it's metal). This would involve drilling a hole in the frame and tapping it (I think it's 10x32 but check) and using special green screws. You can buy the green screws and pigtails you need at any hardware or big-box store.

The complication here is that the metal on a switch has to be grounded even when the cover is off of the box.

my neighbor did an historic restoration and kept the 1800's button light switches, and it all met code.

The trouble with the old switches is that there are usually only two wires, the black (hot) and white wires that complete the circuit. For safety's sake, there should be a separate bare copper ground wire grounded to the circuit ground and connected to the switch frame, yes by that green screw. Pull one out and see how your switch is wired (turning off the breaker/fuse to that switch first, of course). Then you'll know whether you need to replace or rewire the switch. Don't continue to use the switches if they are not grounded.

I expect you'll be able to re-use the visible parts, perhaps even including the botton covers. Keeping old materials is always a good thing, but if you need to replace the "guts" of the switches with modern equipment, don't hesitate. There's absolutely no need to have un-safe wiring or switches just for historical accuracy. Unless you also want to have only hand-drawn four-man fire pumpers used to extinguish any fires. Leather fire buckets can also still be purchased at antique stores....... (just kidding!)

Hope the appraisal comes in on the right side of the money and you get your house!

Molly~

To reiterate:
As long as you're rewiring, you'll have a ground connection to which you can connect pigtails from the switch frames. Once you do that, it'll be safe.

These switches are isolated from the metal frame by virtue of their ceramic housings so the pigtails may just be window dressing but they won't hurt.

If you want verification of this, post the question on the wiring forum.

We bought old ones and had them redone.Thers 2 fellows near us that do restoration they have a really nice supply of used higes,knobs,plates etc.

In a word... yes.

My parent's house is a 1903 Queen Anne. It has push-button switches through most of the house. Dad and Grandpa rewired the house in the 1940s/1950s to get rid of the knob and tube wiring.

"The trouble with the old switches is that there are usually only two wires, the black (hot) and white wires that complete the circuit."

If I'm not mistaken, a properly installed switch is only ever installed on the HOT wire anyways. The NEUTRAL should never be in the circuit, or else the fixture will always be powered, even when the switch is off.

"If I'm not mistaken, a properly installed switch is only ever installed on the HOT wire anyways. The NEUTRAL should never be in the circuit, or else the fixture will always be powered, even when the switch is off."

Two conductor cable is routinely used for a switch loop. The white wire is required to be used as the hot from the light to the switch, and the black is then used as the switched hot. The white wire should be marked to indicate it is no longer a neutral, but this is often omitted.

I rewired my entire house and reused all the pushbutton switches that were here. It passed the NYC electrical inspection.

Brick,

"Two conductor cable is routinely used for a switch loop."

Switch loops are great -- if the house was wired/rewired with sheathed cable.

When my Father and Grandfather rewired the house that my parents now own (bought it from Grandma and Grandpa's estate), they pulled individual wires through much of the house due to the construction.

Few, if any, switch loops to be found.