I am in the process of planning a double garage- the architect has drawn up some plans and specified a box section lintel over the garage door (span of 5m). After some thought I have decided I would like the lintel to be infilled with bricks as per the attached photograph- hence box section lintel will no longer be suitable. I am going to discuss this with the architect later this week but just wondering what type of lintel will be used in this situation? Can an rsj be used and infilled with bricks or ? The main walls are of single skin blocks laid on there flats and the lintel will be supporting a hipped roof as per attached photograph.