Buyers should consider everything when making an offer. The best person to answer your question, is the buyer's agent that you are currently using. If you are not using the expertise of a buyer's agent, and going straight with the listing agent,; then, that's another story altogether.
For example, is the house priced right? Would you lose the offer if you ask for too much in a multiple offers market? Is the roof still serviceable, or too many repairs on it?
And finally, how important is the house to you, if the roof stays as it is?
Talk to your agent about your concerns. If you do not have an agent, or have not place an offer on a house, contact an expert on this board to represent you, or contact me.
Realtor, Certified HAFA Specialist (CHS )
Coldwell Banker Residential