# waterproof back of smartside siding?



## pwa (May 10, 2011)

Hi to all, I am putting lp smartside siding on a garage thats fairly protected from the weather in Idaho. It going over sheathing with tyvek on it but any water inturusion has me wondering if the backside should be primed and painted or waterproofed somehow.I cant find any info on how to treat the back? Thanks for any advice


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## joecaption (Nov 30, 2011)

Only place I would seal it is along any cuts, the bottom edge, and a few inches up from the bottom edge on the back side.
Installed correctly there should never be water on the back side, but sealing the bottom will help prevent back splash damage.

Just a guess, are you installing this because the buildings to close to the ground and the old siding it rotting out?


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## pwa (May 10, 2011)

No, this is new consturction.The water issues just scare me a lot.I have installed aluminum soffit and noticed most times a piece of trim is used to cover the flange of the J channel then the siding with a 3/16 gap for caulk and exspantion


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## joecaption (Nov 30, 2011)

One good reason to always build the roof with an over hang, make sure there's Z moulding over the top of the window. Adding gutters also helps a great deal with the splashing and the run off.
If your going with Smart Side why are you using J moulding around doors or windows?


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## pwa (May 10, 2011)

The J channel is only in the eve's where the soffit is installed. I will have to get z flash for over the doors and windows(did'nt know about that one yet) and I do have gutters.


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## LPSmartSide (Jul 20, 2012)

Glad to hear you selected LP SmartSide for your project. I recommend that you contact LP customer care at 888.820.0325 to address your specific question about waterproofing. And I’ll check to see if we have any information that addresses this specific situation. Thanks, Pat


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## LPSmartSide (Jul 20, 2012)

pwa,

Some in the industry may perceive back priming as performance enhancement but it isn’t necessary for LP SmartSide siding and trim. In addition to qualification by an independent 3rd party, our successful internal testing of LP SmartSide siding in Hilo, Hawaii, (>170 inches of rain annually) consists entirely of siding without back priming. Thank you, Patrick


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