I’ve a big metal shed thing that is bolted to a brick wall base. Some of the bolt heads have started to rust off and so am a bit worried that if the wind gets up it might end up in Kansas. Any suggestions on how to decide on a suitable bolt per sqm of wall space?

Initial thinking was something like the easy fix shield anchors that come with a metal ‘rawlplug’ from screwfix but no idea on how long to go for or diameter.