That house has been renovating for a long time.

That house renovation has been a while.
That house has been renovating for a long time and not complete yet.

How to say the renovation has been a long time.

That house renovation has been going on for a while.
That house has been being renovated for a long time and (renovation) work is not complete yet.
Renovation (work) on that house has been going on for a while.

Thanks.

I feel that the passive present perfect continuous ‘has been being renovated’ is best avoided in that sentence. You really need to rewrite it - That house has been undergoing renovation …

It is technically possible, but never used (by us, here) since it looks absurd and awkward. We do not passivize the following tense constructions:

Past/present/future perfect progressives.
Future progressive.

Accordingly we have eight tense constructions in the passive voice and 12 in the active.

I agree it is better to avoid it.

YOU, upon whom others look for reliable answers/clarifications, should could have avoided it there.

If I had chosen to ignore the original pattern, yes, I could have.
That is not the choice I made, and I was perfectly at liberty to do just that.

I always tend to retain the original version/pattern as far as possible. However, I do not compromise on what I think is absolutely unacceptable. Yes, that is my liberty which, I hope, you will appreciate!

Neither do I. You obviously think what I wrote was acceptable… or have you forgotten your earlier message?

NO.