Building Performance Knowledge Community

We are using James Hardie Reveal Panel with the Fry Reglets on a couple of projects in the office, but we are slightly concerned with leaks.  We know this is intended to be a rain screen and we're detailing it that way, but wanted to poll the masses on this.  For those with experience on this product--

Have you had problems with installers building the system correctly? With furring, reglets, screw pattern...
If installed correctly, any issues with water intrusion?
Any experience with how the panel does in a flood condition?
Anybody attempt to put rigid insulation between the furrings?
Any other words of wisdom?

Oh, should mention, project region is central Virginia/Blue Ridge Mtns area.  Multi-family, five stories.

Thanks!

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Andrew Craven AIA
Architect
Lyall Design Architects
Virginia Beach VA
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We have specified similar fiber cement board rainscreen installations on several projects which have been successful. It's important to understand what this assembly does and does not do. It does leak. It is not a barrier system; it is a rainscreen. Rainscreens shed water, but are not expected to be watertight, especially during incidents of wind-driven rain.

You will need to provide a uniform air and water resistive barrier inboard of a rainscreen, one which will weep incidental infiltrated water back to the building exterior. This is usually done with air and moisture resistive products applied over continuous sheathing, and may also integrate thermal insulation products. There are thin-coat and thick-coat liquids, self-adhering sheets, and mechanically fastened sheets available for air and moisture resistive applications.

Insulation installed between furring will not be terribly successful due to thermal bypasses; the IECC has all but eliminated wall assemblies that lack continuous, uninterrupted thermal insulation. So you'll want to find a way to integrate rainscreen panel supports with an application of continuous insulation and a continuous air and water resistive barrier. You may use a clip and subgirt assembly that integrates with the insulation and air barrier selected. The manufacturers can likely suggest options for attachments.

With a five-story multi-family project, you will no doubt need to meet NFPA 285 with respect to the fire performance of the exterior wall assembly; this will likely eliminate bituminous air barrier products and plastic foam insulation products. This issue is somewhat new in code application and understanding; you should speak with product manufacturer engineers regarding compliance. You may end up using mineral wool board insulation products as continuous insulation, requiring a larger cavity than required for equivalent thicknesses of foam plastic insulation.

As for flood conditions:  fiber cement products are not intended for ground contact nor for extended water immersion.

But you can't beat the view in the Blue Ridge Mountains!

Phil

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Philip Kabza AIA
Partner and Dir Technical Services
SpecGuy
Charlotte NC
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Regarding Philip's comments about NFPA 285 and foam plastic insulation, I have fairly extensive experience with this issue.  Although compliance with IBC Chapter 2603.5 requirements for testing with NFPA 285 is not (in my experience) commonly enforced by building officials, it has actually been in the IBC since the 2000 edition (and is still there in the 2012 edition) so it's not really a new code application.  There now seems to be more knowledge of it by building officials so required compliance on more buildings is likely.  If you wish to use  foam plastic insulation in assemblies complying with 2603.5, I suggest you look at Dow THERMAX  insulation as Dow has extensive testing and engineering judgment letters to support the product. 
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Craig Hess AIA
Elness Swenson Graham Architects, Inc.
Minneapolis MN
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Original Message:
Sent: 11-04-2012 12:03
From: Philip Kabza
Subject: James Hardie Reveal Panel

We have specified similar fiber cement board rainscreen installations on several projects which have been successful. It's important to understand what this assembly does and does not do. It does leak. It is not a barrier system; it is a rainscreen. Rainscreens shed water, but are not expected to be watertight, especially during incidents of wind-driven rain.

You will need to provide a uniform air and water resistive barrier inboard of a rainscreen, one which will weep incidental infiltrated water back to the building exterior. This is usually done with air and moisture resistive products applied over continuous sheathing, and may also integrate thermal insulation products. There are thin-coat and thick-coat liquids, self-adhering sheets, and mechanically fastened sheets available for air and moisture resistive applications.

Insulation installed between furring will not be terribly successful due to thermal bypasses; the IECC has all but eliminated wall assemblies that lack continuous, uninterrupted thermal insulation. So you'll want to find a way to integrate rainscreen panel supports with an application of continuous insulation and a continuous air and water resistive barrier. You may use a clip and subgirt assembly that integrates with the insulation and air barrier selected. The manufacturers can likely suggest options for attachments.

With a five-story multi-family project, you will no doubt need to meet NFPA 285 with respect to the fire performance of the exterior wall assembly; this will likely eliminate bituminous air barrier products and plastic foam insulation products. This issue is somewhat new in code application and understanding; you should speak with product manufacturer engineers regarding compliance. You may end up using mineral wool board insulation products as continuous insulation, requiring a larger cavity than required for equivalent thicknesses of foam plastic insulation.

As for flood conditions:  fiber cement products are not intended for ground contact nor for extended water immersion.

But you can't beat the view in the Blue Ridge Mountains!

Phil

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Philip Kabza AIA
Partner and Dir Technical Services
SpecGuy
Charlotte NC
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