I have roughly dug out the footings for my new conservatory, i am hoping to set the levels tomorrow before pouring the concrete this weekend. I want to ensure the footings will be square to the house wall and also the the walls will be square to each other. If the size of the footings are 5550mm wide and 4000 from the house wall to the exterior of the new walll, do i then measure from corner to corner to see if its square ? And if so, what should the measurement be ? I cant decide how i would go about working this out. Any thoughts guys, and galls Cheers.