The most ideal condition for washing and detailing the exterior of your car in Ottawa is in a controlled indoor environment. You typically don’t want to wash & detail a car in direct exposure to the sun.
The reason why it’s not advisable to wash a car under direct sunlight is because the sun will dry up the hard mineral filled water and soap scum. This will consequently leave the paint with damaging water spots or water marks and streaks. It can be tough to remove these paint defects from a car without more expensive methods like polishing/buffing.
There are a ways to prevent this including using spray wax, carnauba wax or ceramic coating to prevent water from being concentrated in an area.
At Ginious Auto Mobile Detailing, if washing a car in direct sunlight is inevitable, then working in sections is recommended. Working on section(s) or panels at a time is very effective. If not ready to dry the car completely, then it’s important to keep the body of the car relatively wet. Doing this will minimize/eliminate the risk of leaving dried up water spots.
A more efficient approach would be to setup a canopy and work under a cooler more favorable condition. This way the car can be detailed at a more comfortable pace and produce showroom quality results.