Timber frame infill over cavity wall/steel lintels

[lookseehear]

Looking for some assistance with a detail:

 

Need to infill above this window on gable end (lintels are steel beams on inner and outer leaves). The builder doesn't want to use masonry because it won't tie into the steel and he thinks it's just going to end up unsafe. He suggested timber frame, but I guess it would need to be strapped down, which is again problematic over the window.

 

If we go with a timber frame, do you think straps either side of the steel would be sufficient? Timber frame just on the outer leaf? or on both?

 

Any alternative ideas?

[markc]

Ties welded to top of beams or bent strap ties bolted or shot nailed onto top of beam will tie the blockwork in. 

[lookseehear]

Thanks - I like this idea. I assume I'd need to get the SE to confirm it's OK before we start drilling holes in the top flange, or am I OK if the holes are small and not drilled in the web?

[Russell griffiths]

Twin stud wall, full fill with rockwool type insulation, take the insulation down between the steels also. 
long straps from 3 courses of blockwork down to timber studs. 
thar ridge beam will need a fair bit of insulation around it too. 

[torre]

With something similar using masonry our SE specified expamet fixed to the top of the horizontal steel and wall starter ties fixed into the sides of the vertical (we used self tapping screws)

 

Maybe it's just unclear from the photo but is your steel at the far end sat on blockwork rather than a padstone!?

[lookseehear]

3 hours ago, torre said:

Maybe it's just unclear from the photo but is your steel at the far end sat on blockwork rather than a padstone!?

 

Padstones both sides, but on the left there's another column of blocks because the opening was the wrong size initially.

[lookseehear]

5 hours ago, Russell griffiths said:

thar ridge beam will need a fair bit of insulation around it too. 

 

Aiming for ~100mm of Knauf Omnifit above it. I'm fully filling the rafters with 150mm Omnifit and I'm hoping it will be not too tricky to get around the ridges and junctions.

[Oz07]

Why is this any different to a normal gable. Some straps off the timber at the top of the wall built into the inner leaf. Job done. Why complicate it? What am I missing? Some wall start ties tek screwed into that steel post if advised by se.