I wish I had asked this question when I renovated my 100 year old house several years ago! I just plunged in and, years later, I have no prayer of recouping all my costs, and I have to be satisfied with just really loving living in my home!
If I had it to do again, I would ask this question of a respected real estate agent in your area who knows your market well. I agree with Jennifer and Sarah, but also dug in to see if there are any numbers that could provide a rule of thumb on this. I did find a little information we can share.
First, in many markets, a bathroom renovation slightly outpaces a kitchen renovation in supporting resale value. I’ve been told that the main reason for this is that lots of people want to design their own kitchen, more so than the bathroom.
The key issue here, however, is that on average, the data suggests that neither project actually fully pays for itself in resale. Done right, you still will only be able to recoup about 2/3 of what you’ve spent on these renovations, based on the averages. So, like me, you have to love what you are doing and want to enjoy them yourself enough to justify the project.