What is mixed wall construction?

So, a common question we get is around wall constructions and what consists of a mixed wall construction. Now, a mixed wall construction is where you’ve got a mixture of rigid and flexible wall constructions. Rigid is concrete or block work and flexible is a stud work system. Where you’ve got a mixture of these creates a bit of a problem if the door that is going into the hole with a mixed construction so you may have a rigid construction on one side with flexible across the top and down the side or in different applications, it needs to be tested in that scenario to be certified accordingly.