lintel above bi-folding door

[seka1980]

hi there
im just starting to plan out my new single story with flat roof extention and need some advice on the lintel to use above the 8ft bifold external doors!!!

in the pic attached they give instructions for a pressed steel lintel and an rsj, because there arnt many courses of block work (thermalites) between the top of the doors and the roof , will using a catnic be OK as i was worried that the lack of weight above the doors may cause problems?
also are RSJs ever used on external walls and if so how are they finished eg renderd over

Untitled

• seka1980
• 13 Aug 2010
• 2

cheers
jon

 

[freddiemercurystwin]

Normally when a UB is used above a large window opening a leg is welded to the bottom flange to support the outer skin. They can be rendered over here's how I detailed a recent head over such a door

Untitled

• freddiemercurystwin
• 6 Aug 2010
• 4

 

[Blagard]

here's how I detailed a recent head over such a door

freddymercurystwin
I'm intrigued as to why you chose an RSJ and flange instead of a Catnic or similar. Was it due to the opening width being out of the range of typically available catnics, your preferred method or some other reason?

seka 1980
I would not expect you to have any problems with a properly fitted catnic.

Were you concerned about the catnic moving? If the mass of the bi-fold doors was so great to be of a concern, you could always add some straps to the Catnic/Wall joints for your peace of mind!

 

[freddiemercurystwin]

Opening was 5.4m.

But for the OP's info the principle is the same be it a Catnic with a leg or a UB.