Seattle home inspector shares clues to LP siding failure

[KIKOGZZ]

The biggest cause of water intrusion and rotting is calulk. It will fail fast with normal expansion and contractioin. The box on the video had a line of caulk on the top that had separated. They should have used a Sturdie Mount Box or a Tamlyn horizontal z-bar over it as it is done with windows to prevent that mess.

[stebnitzbuilders]

Let's remember, too, that the problems LP had with this product was corrected. When the first generation siding came out, the factory treated the entire sheet with its proprietary solution that protected the siding. When problems arose, they fixed it. The next generation siding treated every flake of wood that came through the process rather than the sheet as a whole. This seems to have solved the problems they had. Stebnitz Builders uses SmartSide and will continue to. It's a great product.

[Kerty77]

LP does swell badly at the butts over time. Also the nails will be sucked in due to swelling.

[brucebolivar]

I worked at an LP siding plant. What is seen in this video is actually a blemish on the press plate from when they made a repair to the plate. This does not hurt the siding structure, just the cosmetics. Most siding failure is due to paint not sticking from factory.