Without physical support. / For which support or help is not available. / Without confirmation from a credible source, without verifying support / Not supported by or borne out of evidence or facts.

Not supportive.

Not able to be supported or endured.

That serves no supporting purpose in a structure. / Unsupportive.

the state or quality of being unsupportable

in an unsupportable manner

In an unsupportive manner.

The quality of being unsupportive.

the state or quality of being unsupportable

Without support.