I am looking at removing a single skin internal wall which runs perpendicular to the rear external wall of the house. A steel beam will be inserted as the wall is load bearing. What I am concerned with is whether the internal brick wall acts as a buttress to the rear wall? The external wall is only 6m long. Building regulations discusses "long" walls needing internal buttress walls but doesnt give any length for "long" walls. Is it safe to assume that a 6m wall doesnt need an internal buttress? The wall in question is only single storey and there is no perpendicular wall on the 1st floor. Any help greatfully received.