What you need to do is to read the fine print. Each hotel will differ. In general, yes all hotel should give you fair warning about anything that might make your stay difficult. However, you have to consider a few points as well.
First, seven months is long time. So, if you want the same room for seven months, it might be too much to ask. Of you insist on staying seven months in the same room, you will have to make that known right from the beginning.
Second, there are emergencies that happen. So, perhaps the renovation is due to some other underlying problem. If this is the case, then I can see where the hotel is coming from.
Third, did the hotel compensate you for their moving you? They should at least do this, especially in view of the fact that you are staying there for seven months.