Using a steel UB in a valley

[garyo]

Here's one we did last week.....

That's pretty much my design, although in a dormer bungalow format, so imagine two courses of blocks beneath the wall plates is where I have some floor joists- therefore no practical way of preventing roof spread other than a structural ridge.

Nose - do you have any more photos of the build up of your gable ladder? I can't decide if I should over-sail my ridge and wall plates and then just have another set of common rafters floating outside to take the barge boards, or whether to do it in small cross section timbers using a ladder design. What did you do in that scenario?

 

[John D v2.0]

Yes, it stops the roof spreading.

Not at the moment, well, it will when the end of the beam is supported, but now it's just the stiffness of the rafters and the tops of the walls.

 

[noseall]

Nose - do you have any more photos of the build up of your gable ladder? I can't decide if I should over-sail my ridge and wall plates and then just have another set of common rafters floating outside to take the barge boards, or whether to do it in small cross section timbers using a ladder design. What did you do in that scenario?

I fixed 100mm x 50mm timber nogg's to the last rafter (600c/c) then fixed the barge boards direct to the ends of these noggins. All the existing eaves details to the main house shows close butted fascias and barges i.e. zero soffit. I allowed 10mm overhang of the noggs past the masonry. This 10mm plus the 20mm fascia board amounts to the 30mm lip you get with the plastic fascia cap.

 

[garyo]

I fixed 100mm x 50mm timber nogg's to the last rafter (600c/c) then fixed the barge boards direct to the ends of these noggins. All the existing eaves details to the main house shows close butted fascias and barges i.e. zero soffit. I allowed 10mm overhang of the noggs past the masonry. This 10mm plus the 20mm fascia board amounts to the 30mm lip you get with the plastic fascia cap.

I think I'll do the same but use my rafter offcuts which will be 175 by 50. Then I can have a 200mm soffit overhang and nail the soffit direct to the bottom of the noggin ladder.

 

[23vc]

Here's one we did last week.....

20170322_085233

• noseall
• 30 Mar 2017

20170322_085235

• noseall
• 30 Mar 2017

Totally hijacking the post sorry gary but what is the mesh for on top of the course of blocks?

 

[noseall]

what is the mesh for on top of the course of blocks?

Masonry joint reinforcement. The daft SE thought we needed it in both the block and the brick courses. He also wanted straps on the rafter tops where they join - which we also did.
They have to allow for crap brickies and poor joiners.

 

[23vc]

Wow. I've seen the rafters strapped before but whats the mesh supposed to be preventing, the roof spreading and splitting the gable wall? Is it just on that course?
Thanks for the info it interests me, I don't get out much

 

[noseall]

Is it just on that course?

Every block course above the lintel and every third course of bricks.

 

[noseall]

whats the mesh supposed to be preventing

No idea. Just cautious I guess with there being a large opening below.

 

[tony1851]

Every block course above the lintel and every third course of bricks.

As a matter of interest, did they specify stainless steel mesh or galvanised? Galvanized is OK on the inner skin, but if any is on the outer skin, it should be s/steel.
(I was caught out with this some years ago; the galvanising soon breaks down in an outer skin due to the dampness).
In any case, if the SE specified that as some sort of tensile reinforcement for the masonry, coiled mesh is not advised for that purpose - the proper stuff for that purpose is the stainless steel ladder frames made by Ancon.

 

[noseall]

Both the architect and the BCO raised eyebrows about the reinforcement and neither would have been bothered if it went in or not. I'm not even sure whether it was galv or SS. The SE did recommend the Ancon ladder type but I could not get any locally.
I'm sure that gable will be ok. Just like the other dozens of similar ones I've built without it.

 

[garyo]

He also wanted straps on the rafter tops where they join - which we also did.

What do you strap them with - something specific for that purpose or general builders band or restraint straps? I might put some on my own ridge because I like to over engineer things.

 

[noseall]

What do you strap them with - something specific for that purpose or general builders band or restraint straps? I might put some on my own ridge because I like to over engineer things.

Don't do it. It makes fixing the tile battens a PITA.