Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Attach Dens Glass to HSS Header

Status
Not open for further replies.

TylerM94

Structural
Jun 2, 2020
26
I need to provide an attachment detail for dens glass sheathing at window heads that have HSS steel headers (not typical Cold Formed Studs) and the contractor has requested powder actuated fasteners. I found a nice self-drilling Hilton fastener (Kwik-Flex) with an undercut head to allow for the fastener to be driven flush to the dens glass. The contractor pushed back on this and asked for powder actuated fasteners. My concern is there is much less control of depth of penetration with powder actuated. This leads to a risk of the contractor over driving the fasteners and creating areas where the sheathing is prone to cracking in flexure as wind suction acts on the wall.

What are my options here, would you consider powder actuated?
 
Replies continue below

Recommended for you

I can't imagine PAF's working in this situation. What about a polyurethane construction adhesive? Short of that, I would use tek screws as you already suggested.
 
Using powder actuated fasteners to fix densglas board to structural steel?

Why not save yourself a couple bucks on the powder actuated pins, and just take the densglas board and put it in your kitchen blender. Should yield similar results.
 
Simpson has a series of PAFs for wood that have large washers. Something like that may work.

Better plan: raise the header 1.5" and fasten wood blocking to the underside. Fasten the densglass to the blocking.
 
weld threaded studs onto the HSS and attach 2x lumber to it. Then window will screw onto the lumber.
 
I know that this is a bit of a cop output are you using denseglass for a structural purpose? Do you really want to be the one who says how to fasten this? Afterall your talking about attachment of a moisture resisting element, there could be repercussions of using the wrong fastener that aren't in the structural scope IMO. Perhaps your already stuck with this task, but in the future you might consider showing the fasteners as 'fasteners by others', or 'fasteners approved by sheathing mfg'. etc.

Basically I see structural scope for this as being the ones who provide the base material for the fasteners. You can give them steel of XX thickness, or you can give them wood attached to your steel like others have suggested. I think a low velocity PDF with a washer might work like pham has suggested.
 
Thank you all for the helpful suggestions. I have a lot to consider here. Going forward I am going to try to steer clear from providing attachment of non-structural sheathing since it is really outside of my scope and causing some headaches. For instance, I suggested 2x wood attached to the HSS as furring and got the follow up question of whether it needs to be fire resistant. For fire resistant wood, the fasteners need to be corrosion resistant. I appreciate the helpful responses and I am most likely going to suggest either fire treated wood or a hat channel attached to the HSS.
 
PAF's will blow through the DensGlass. TEKS screws will work or fasten wood nailer with PAF's then screw the DensGlass

 
If wood is a problem, they could fasten a cold-formed steel stud or track with PAF to the HSS and then screw the Densglass to the CFS.
 
Just use tek screws since it is likely what is being used for the remainder of the densglass attachment. Contractors are going to complain about everything if they already have their mind made up on how they want to do things. You could also add some light gauge furring instead of wood so you don't have to deal with the fire resistance.
 
They used to have a 'pointy' bevel sharpened (about 1/16" dia wire) accessory that was adhered to concrete walls and the insulation and wallboard was pushed onto the spike with a metal 'cap' pushed on to it and the spike was snipped off so there was no point. I don't know if these are still available and whether they could be used. I couldn't find anything, but apparently they have low velocity PAFs for this too...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor