lintel over window aparture on non loadbearing wall

[Henners]

There seems to be a general rule of 150mm bearing for lintels on loadbearing walls.

Does the same reasoning apply to non loadbearing walls?

I want to install a new window (0.631 * 0.900) on the first floor in an external non loadbearing wall. Do I still have to allow a 150mm bearing at both ends. In other words do I have to install a 1metre Catnic CG50/100 or similar.
Thanks.

 

[noseall]

yes, the 150mm rule will apply to all lintels, though it used to be 100mm when i were a lad. what makes you think an outside wall isn't load bearing. the inner skin of an outside wall will be carrying the roof, surely?

 

[Henners]

Would have thought that two wall carried all the roof loading and the other two was just masonry loading.
Is this incorrect

 

[noseall]

if its a gable end then yes, unless theres a purlin in the roof?

 

[Static]

All external walls should be considered load bearing. Lintels come in increments of 150mm so for a 900 opening pick a 1200mm long lintel. Also if you phone catnic and discribe what/where your putting the opening they will give you a lintel spec.