[gr8fl4porsche]

Unless your house has deep grooves or very porous stucco, there is no need to back brush after you spray - unless you cannot spray well enough to ensure a uniform appearance. Paint adheres with a mechanical bond and a chemical bond. Mechanical bond being any small to microscopic grooves in the surface. Most of the adhesion is by chemical bonding.

Do not spray your house when it is too hot. The paint will dry prematurely and affect the chemical bonding.