Q.Do wisteria tendrils die if you cut them off
Do wisteria tendrils die if you cut them off from their root supply? Mine turned brown but are still attached to my house’s siding. Wisteria bloomed once in whole ten years it’s been planted. Not invasive except for growing up side of the house. I had it supported by cheap plastic trellis, which it never bent or gnarled. Hired some painters (who I fired) who said it was impossible to remove them and wanted to paint over the tendrils. They says tendrils are growing under the siding, but tendrils are brown, have no water source, and have not grown since cut off from the rest off the plant about a year ago. I am a senior citizen and cannot climb up a ladder to the second story of our house to see alleged damaged for myself. I have to take the painters’ word for it but I think it’s a scam.

The vines if cut from plant are no longer alive. They in fact though may be very attached to your home, it's siding and have invaded under the siding. Wisteria is extremely invasive and if attached to a home can do great damage.
I would recommend you have a professional inspect your home and have the vines removed.
Best of luck.
Here is a link that discusses removal of Wisteria Vine.