Hardie Panels 1

[msquared48]

Anyone know what the maximum recommended deflection ratio is for the panels?

I can't find anything in the ESR's, and their technical help line is really lacking.

Thanks.

Mike McCann
MMC Engineering

 

[dhengr]

Mike:
I’m really not sure what you want or mean, and I don’t have the ICC-ESR in front of me. Don’t they show any mechanical properties and section properties in their report, which you could use to do some deflection calcs? Could you compare this to other sheet or lap siding values and recommendations, as a guide line. Don’t they have some support spacing recommendations for their various products? I would try actually talking with someone in their engineering dept., I just haven’t had much luck with the half-assed responses we get from an e-mail exchange. These days, everyone wants a new product to bring to the market, but then they do a damn poor job of testing and proving or disseminating pertinent design info., or of customer service and designer service before problems with the product start showing up. We are their guinea pigs or testing service these days, and ten year later we can sue them for satisfaction of a problem if we can find them or afford the suit. I do know that the products will wick-up water, so you want to keep them (their butt/cut ends or edges) well above any water level (roof plane, grade) which might cause this.

 

[EngineeringEric]

Are you wondering about what sort of deflection they can undergo before showing signs of failure (like L/360)?

 

[msquared48]

Well, we have to attach antenna arrays to the side of a wood building with 2X6 stud walls, plywood sheathing and Hardie panel siding. The horizontal and vertical loading from the antennas will cause the wall studs to deflect, and I was wondering what the Hardie panels could tolerate as they are attached to the studs. May turn out not be an issue, but I thought I'd ask.

Mike McCann
MMC Engineering

 

[EngineeringEric]

It is my understanding that the panels are designed for a typical L/180 or 240 design. In my experience the boards are pretty flexible and it would be my assumption that the boards can probably deflect more than i would like my studs to. But you made me do some searching and there isn't much literature out there.

 

[CELinOttawa]

Very flexible... Typically governed by the deflection limit of what is attached to them (ie: Tile, brick, etc).

 

[dcarr82775]

I agree with EE and CEL. Those things are plenty flexible with respect to the stud wall/gypsumboard.

 

[msquared48]

Thanks all...

Mike McCann
MMC Engineering