The answer nobody wants to hear is Yes. Cape Town city council does require a plan for the addition of a patio roof/awning, it is best to obtain the plan & council go-ahead before installing the awning to prevent any fines & a mad scramble to update your house plans before the sale of your home.
Here is a link to the Building-Plan-Preparation-City-of-Cape-Town.pdf, but don’t stress we can refer you to architects that know our products & will draw up the necessary plan & walk it through council for a reasonable fee (see our partners page).
Some awning installers will tell you, you don’t require plans, best to confirm this with your local council office. We as installers don’t require a plan, but you as the home owner do. If you have a body corporate where you live it’s best to check their requirements as well before installing a patio roof/awning.