When you think about calculating the average time it takes to complete interior painting, it's usually one room per day per house painter. So, if you have an average-sized house of 1,500 to 2,000 square feet, it will take you 3 to 5 days to complete the interior painting. On average, it takes about 4 days to paint a medium-sized house. But it all depends on several factors.
The most important ones include the size of your house and the size of your painting equipment. Larger houses take longer to paint than smaller ones.