The spider in your photo appears to be a gray cross spider or bridge spider, scientific name: Larinoides sericatus, in the family: Araneidae. The scientific name of this spider until recently was considered to be Larinoides sclopterius and much of the information you can find about it will still be listed under L. sclopterius. This species usually has fairly distinctive markings, but the coloration can be quite variable. This species is widespread across the northern U.S., however, it may have been introduced from Europe where it also occurs. These spiders are usually found near water and originally probably lived on cliffs. However, they have substituted bridges and buildings as places to live, but again usually near water. They usually do not spin their webs among vegetation, preferring the steel beams and eaves of man-made structures as their homes. The spiders usually hide during the day and come out onto their orb webs at night to capture prey. Lights on the bridges and buildings, and especially lighted windows attract many kinds of insects, especially those that emerge from lakes and rivers. Thus the bridges and buildings are perfect places for the spiders to live and find food. Apparently these spiders are becoming much more common in and around homes, as I now receive frequent requests to identify them. Adults may occur all year, but they lay their eggs during the summer and fall. These types of spiders are not considered poisonous, nor prone to biting. One reference I found indicated that any bite would be somewhere between a mosquito bite and a bee sting in severity. If you search the internet for bridge spider or Larinioides scolopterius, you can find more information and images of these spiders. I have included a link below to a webpage that you can also quickly check out.