I am designing a home that will have a fiber cement rain screen. I am thinking of getting hardie board 4' x 8' sheets and cutting them down to a 1'x4' panel.... has anybody done something like this? I am trying to figure out what the best way to attach the fiber cement system to the substrate. I know Hardie board reccommends furring master for their typical lap siding rain screen systems but they have nothing documented on a detail like this.
thanks in advance!
gwharton
Oct 23, 13 12:24 pm
This is a very common detail in the pacific northwest, where water penetration issues are a big deal. There are several ways to go about doing it, depending on how high-quality vs. inexpensive you're looking to go. Hardie does not have a turn-key system for doing cladding like this, but it's very commonly installed as a quasi-rainscreen.
I say "quasi"-rainscreen because unless you leave all the joints open, the system won't actually be a rainscreen. It will just be a cavity wall cladding system. Rainscreen systems require pressure equalization, which requires careful attention to air barriers, blocking, and allowing air to pass freely through the exterior finish system. Just because it has a drainage cavity behind the finish doesn't make it a rainscreen.
Hardie will not give you a warrantee on their product if you cut the panels and leave the cut joints exposed to weather, so it's very rare to find Hardipanel used in a true pressure-equalizing rainscreen design. It's much more common to find it used in a board and batten over strapping configuration: the strapping provides a drainage cavity behind the finish cladding, which is a more conventional board-and-batten system. The battens cover the exposed panel edges and protect them from water exposure.
For a little while, Hardie sold a higher-density product in the USA intended for commercial installations that didn't have the cut edge swelling problem and could be warranteed in an exposed edge system. It was called Matrix. It's since been spun off into a separate business unit called Scyon and may no longer be available in the USA.
Another issue with using standard hardipanel over a drain cavity with strapping behind is that panels are actually quite thin and surprisingly flexible. They telegraph any and all imperfections in the sustrate to the finish surface. Another complication is that you'll have to pre-drill all your screw holes, particularly any which would be located within 3" of a panel edge. As a fiber-cement product, the material is actually quite abrasive. Expect to go through a lot of drill bits and saw blades.
If you're going to go this route, make sure you pre-prime all your panels before installation, both front and back side. Try to install raw edges up and cut edges down. For strapping, you'll need to choose between 1x3 cedar or Trex. The cedar is cheaper, but the Trex gives a much higher-quality end product. If the joints are open and the strapping is exposed, definitiely consider going with Trex strapping, both for longevity and appearance.
If the system is just a cavity wall with mostly closed joints, you can get away with putting two layers of building paper at the drainage plane. If the joints are open (true rainscreen style) you'll need to upgrade to a UV-resistant air barrier product. Building paper is not suitable for that application and will degrade quickly. It also won't keep the water out because it isn't an air barrier (the main property the drainage plane needs in a pressure-equalizing system).
swegin
Oct 23, 13 12:55 pm
Thank you for your insight gwharton! I appreciate it. I am looking at leaving all the joints around the panels open (1/4" gap) and was intending on using either vaproshield or delta fassade-s water ressistive barrier. I did not think of using trex, that seems like a great idea. especially because I am wanting an 1"+ air barrier between my structural wall and the back of the panel. (I am planning on painting the panels dark charcoal or black, so I want to reduce the thermal heat gain due to the dark color) my biggest worry is something that you gwharton brought up....the flexibility of the hardie board. I do not have any set plans on using hardie board, I am open to any fiber cement manufacturer. Is there one out there that makes a thicker board so that the panel can be more rigid? or could I simply go to a 12" o.c. spacing of my furring strips instead of the typical 16?
SneakyPete
Oct 23, 13 1:06 pm
The following website has details for what they consider the best rainscreen application.
They have details and such to download. It may help you get some ideas.
I am not affiliated with them, but I have talked to their design folks and they're quite willing to help answer questions.
swegin
Oct 23, 13 1:11 pm
Thanks sneakyPete, I will browse their website and see what I can find!
wurdan freo
Oct 23, 13 1:21 pm
Is there a reason why you need to use fiber cement? ACM would be much better for holding your shape and will come factory painted. You can use a panelized system or face fasten.
swegin
Oct 23, 13 1:32 pm
isn't ACM alot more money psf than a fiber cement board system?
wurdan freo
Oct 23, 13 10:48 pm
Sure...but fiber cement is a lot more than LP smart side or vinyl siding.
JeromeS
May 3, 16 11:40 am
old thread -
Anybody know of any products other than Hardi suitable for rain screen application. A quick search reveals Kliptech EcoClad but their website seems to be in disarray. Paperstone used to make something similar, but I don't see it listed any longer in their product offerings.
lamp4036
May 3, 16 11:46 am
Equitone is pretty nice, but also pretty expensive.
I also just came across Nichiha the other day. I haven't researched them, but I like the ship-lapped joints vs true open joints.
Good info for anyone looking to use Hardie in an open joint system from gwharton above. Hardie does not endorse it, nor will they warrant it. It is cheaper, yes, but not appropriate material for open joints.
Everyday Intern
May 3, 16 12:11 pm
Related and loaded question; with an open joint cladding how many open joints does it take before the cladding becomes a fence? Same question for perforated metal cladding; how many holes does it take before the cladding is simply chain-link fencing?
archanonymous
May 3, 16 12:14 pm
Swisspearl
Equitone
Hardi
Shera
Synstone
Cem5
American Fiber Cement Corp
proto
May 3, 16 12:36 pm
in lieu of fiber cement, there's phenolic resin panels (some have real wood veneer on them) or plastic core composite metal panels
neither of these compete on price with the traditional residential spec materials from hardie and certainteed
MEG panels
Richlite
Alpolic
JeromeS
May 3, 16 1:27 pm
yeah - residential focus - DIY cost spec. for my own house...
Hey all-
I am designing a home that will have a fiber cement rain screen. I am thinking of getting hardie board 4' x 8' sheets and cutting them down to a 1'x4' panel.... has anybody done something like this? I am trying to figure out what the best way to attach the fiber cement system to the substrate. I know Hardie board reccommends furring master for their typical lap siding rain screen systems but they have nothing documented on a detail like this.
thanks in advance!
This is a very common detail in the pacific northwest, where water penetration issues are a big deal. There are several ways to go about doing it, depending on how high-quality vs. inexpensive you're looking to go. Hardie does not have a turn-key system for doing cladding like this, but it's very commonly installed as a quasi-rainscreen.
I say "quasi"-rainscreen because unless you leave all the joints open, the system won't actually be a rainscreen. It will just be a cavity wall cladding system. Rainscreen systems require pressure equalization, which requires careful attention to air barriers, blocking, and allowing air to pass freely through the exterior finish system. Just because it has a drainage cavity behind the finish doesn't make it a rainscreen.
Hardie will not give you a warrantee on their product if you cut the panels and leave the cut joints exposed to weather, so it's very rare to find Hardipanel used in a true pressure-equalizing rainscreen design. It's much more common to find it used in a board and batten over strapping configuration: the strapping provides a drainage cavity behind the finish cladding, which is a more conventional board-and-batten system. The battens cover the exposed panel edges and protect them from water exposure.
For a little while, Hardie sold a higher-density product in the USA intended for commercial installations that didn't have the cut edge swelling problem and could be warranteed in an exposed edge system. It was called Matrix. It's since been spun off into a separate business unit called Scyon and may no longer be available in the USA.
Another issue with using standard hardipanel over a drain cavity with strapping behind is that panels are actually quite thin and surprisingly flexible. They telegraph any and all imperfections in the sustrate to the finish surface. Another complication is that you'll have to pre-drill all your screw holes, particularly any which would be located within 3" of a panel edge. As a fiber-cement product, the material is actually quite abrasive. Expect to go through a lot of drill bits and saw blades.
If you're going to go this route, make sure you pre-prime all your panels before installation, both front and back side. Try to install raw edges up and cut edges down. For strapping, you'll need to choose between 1x3 cedar or Trex. The cedar is cheaper, but the Trex gives a much higher-quality end product. If the joints are open and the strapping is exposed, definitiely consider going with Trex strapping, both for longevity and appearance.
If the system is just a cavity wall with mostly closed joints, you can get away with putting two layers of building paper at the drainage plane. If the joints are open (true rainscreen style) you'll need to upgrade to a UV-resistant air barrier product. Building paper is not suitable for that application and will degrade quickly. It also won't keep the water out because it isn't an air barrier (the main property the drainage plane needs in a pressure-equalizing system).
Thank you for your insight gwharton! I appreciate it. I am looking at leaving all the joints around the panels open (1/4" gap) and was intending on using either vaproshield or delta fassade-s water ressistive barrier. I did not think of using trex, that seems like a great idea. especially because I am wanting an 1"+ air barrier between my structural wall and the back of the panel. (I am planning on painting the panels dark charcoal or black, so I want to reduce the thermal heat gain due to the dark color) my biggest worry is something that you gwharton brought up....the flexibility of the hardie board. I do not have any set plans on using hardie board, I am open to any fiber cement manufacturer. Is there one out there that makes a thicker board so that the panel can be more rigid? or could I simply go to a 12" o.c. spacing of my furring strips instead of the typical 16?
The following website has details for what they consider the best rainscreen application.
http://www.americanfibercement.com/
They have details and such to download. It may help you get some ideas.
I am not affiliated with them, but I have talked to their design folks and they're quite willing to help answer questions.
Thanks sneakyPete, I will browse their website and see what I can find!
Is there a reason why you need to use fiber cement? ACM would be much better for holding your shape and will come factory painted. You can use a panelized system or face fasten.
isn't ACM alot more money psf than a fiber cement board system?
Sure...but fiber cement is a lot more than LP smart side or vinyl siding.
old thread -
Anybody know of any products other than Hardi suitable for rain screen application. A quick search reveals Kliptech EcoClad but their website seems to be in disarray. Paperstone used to make something similar, but I don't see it listed any longer in their product offerings.
Equitone is pretty nice, but also pretty expensive.
oooh, I forgot about Nichiha!
Equitone
Silbonit from Cement Board Fabricators
Plus the usual suspects like SwissPearl and FibreC.
I also just came across Nichiha the other day. I haven't researched them, but I like the ship-lapped joints vs true open joints.
Good info for anyone looking to use Hardie in an open joint system from gwharton above. Hardie does not endorse it, nor will they warrant it. It is cheaper, yes, but not appropriate material for open joints.
Related and loaded question; with an open joint cladding how many open joints does it take before the cladding becomes a fence? Same question for perforated metal cladding; how many holes does it take before the cladding is simply chain-link fencing?
Swisspearl
Equitone
Hardi
Shera
Synstone
Cem5
American Fiber Cement Corp
in lieu of fiber cement, there's phenolic resin panels (some have real wood veneer on them) or plastic core composite metal panels
neither of these compete on price with the traditional residential spec materials from hardie and certainteed
MEG panels
Richlite
Alpolic
yeah - residential focus - DIY cost spec. for my own house...