Timber frame restraint straps?

[Mcn_selfbuild]

After a lot of searching through the internet I still haven’t found the definitive answer for this post, on my architects drawings for my second storey extension it states three types of restraint straps for the gable end alone.
The new build is a timber frame and i’m Not fully understanding where these three have to go, on a masonary build (as carried out previous) the eaves level would tie into the blockwork and across the rafter, but where do these go in a timber frame?
The new build is joining the existing gable end.

Wall head restraint straps (1000mm centres)
Eaves level gable restraint straps (1000mm centres)
Gable restraint straps (1200mm centres)

All of the above mentioned have to be strapped across three trusses and screwed into appropriate noggins,
Do the gable restraint straps attach the outer blockwork and fit under the gable ladders attaching the trusses by attaching to the underside?

Sorry for the long post, I don’t seem to be getting anywhere with my architect and there has been numerous details on the plans which seem to contradict themselves.

 

[tony1851]

Why is the inner skin in timber frame - why not blockwork?

 

[Mcn_selfbuild]

Long story, the existing house is timber frame. I’m building on top of my garage( which is blockwork, 100mm cavity) the architect said that 6 x 2 timber frame would be needed to meet the energy efficiency. To be fair my previous architect also planned on using the same, but he ended up ripping my off and disappearing into the sunset before I could even get planning permission.

 

[^woody^]

Straps fit to the inner leaf, whether its masonry or a timber frame. The ladder, and normal wall ties restrain the outer leaf

Straps do not need to be on the ladder noggins

Straps can go onto noggins between the rafter/trisses or on a 4x1 on the underside with two nails per rafter.

England b/regs require max 2m centres not 1.2 not sure about Scotland. In practical terms you space 3 or 4 up a normal gable - one about 500mm up the slope then half-way or 1/3 as necessary and one near the apex

 

[Mcn_selfbuild]

Probably going to sound stupid here, but do the eaves level straps go through the osb sheeting and onto the trusses?

I’m familiar with the wall head and gable restraints but not so much the eaves strap. Before I toook the roof of the gable was blockwork and I had these straps at eaves level attached to the outer side of the inner blockwork and onto noggins under the rafters, maybe I am missing something but do the ‘L’ of the eaves straps screw into the top plate of timber frame? Apologies for complicating things

 

[^woody^]

Any sort of horizontal strap needs to hook over the wall it is restraining

 

[Mcn_selfbuild]

You’ll have a sore head from me Woody

on the trust detail on my plans it shows 5 straps at eaves level on the gable, the rest are at the top of the walls which i’m Happy enough with, but these eaves straps are doing my head in.
I can post a pic of the detail later.
I’ve framed the gable end but I’m hesitant to fit th sheething until I’m 100% sure of how I am going to fit these ‘eaves level’ straps @ 1000mm centres

 

[tony1851]

He gives everyone else a sore head.

 

[^woody^]

He gives everyone else a sore head.

There is a sweet spot between the extremes of thick and soft where there is no pain.

 

[^woody^]

You’ll have a sore head from me Woody

on the trust detail on my plans it shows 5 straps at eaves level on the gable, the rest are at the top of the walls which i’m Happy enough with, but these eaves straps are doing my head in.
I can post a pic of the detail later.
I’ve framed the gable end but I’m hesitant to fit th sheething until I’m 100% sure of how I am going to fit these ‘eaves level’ straps @ 1000mm centres

Is this the plan monkey using his own terminology again?

These appear to be gable restraint straps which would be fitted to floor or ceiling joists parallel to the gable

 

[Mcn_selfbuild]

Yes, it seems to be .
I have added the two details, I understand the gable restraint as you explained, the eaves restraints not so much.
Do the eaves straps need to be fitted to the timber frame before the sheething goes on?

 

[^woody^]

Again, south of the border, we would just have those straps on the "longitudinal bracing" shown in the second image, and not that many as drawn on the plan.

The top plate will be bracing the gable panels at eaves level to make it one strong wall, so that many straps seems excessive - but check with your own local regulations.

 

[Mcn_selfbuild]

Thanks again woody, the BC officer is coming out to check the timber frame at the end of next week as I should have the insulation in by then and I will ask, then he’ll be back to check the roof, which I already have in place to make sure i’m Happy that the roofline is matching up, so far so good!
Thanks again!

 

[Mcn_selfbuild]

So today I had the building control officer round and he was happy with the timber frame. He seems approachable so I asked about the ‘eaves restraint straps, normally in this area only gable restraints would be used but I need to check with my engineer to see what is to be used as he hasn’t seen twist straps use for the gable end at rafter level, these are what the engineer has chosen. I was then sent this picture from my engineer, using the same idea as restraining a spandrel panel, shown in the detail to the left