Unfortunately, I can’t be exact on the timeline because every roof is different.  With that in mind, most roofs can be replaced in a day. But the actual timeline depends on factors like the size of the roof, how complex it is, how easy it is to access, and the weather.  It also depends on the type of roofing material you choose. For example, slate tiles have to be installed one at a time which is very time consuming.  Compared to architectural asphalt shingles that come on strips that are (around) 40” long, installing slate tiles one by one takes significantly longer. The more roof decking that needs to be changed out can also make a roof replacement take longer.  In extreme cases, a roof replacement could take three to five days. Depending on the roofing material you choose, the weather, complexity, accessibility, and the size of your home, it could even take up to three weeks.