Why it is important to fill gaps that are not visible

When in comes to exterior painting, it is very important to protect all the surfaces from the weather. As a leading exterior painting company in Perth we make sure that all the gaps and cracks are filled prior to painting, even these ones that are not visible from the ground. This prevents the rain to soak into the timber, concrete or other surface that must be protected. Have you noticed some of the bargeboards or timber trims are cracked/swollen or even rotten? Most of the time its caused by the gaps that have not been filled in first place.