LP siding

[CHI]

I am just entering the home inspection field and I have a question regarding LP siding. I am in the Northwest and I understand LP siding was used extensively up here. Does anyone know of any information available that gives the inspector a failure guideline or what to specifically look for when inspecting this product?

Thanks[:-magnify

[Jim Katen]

Originally posted by CHI

I am just entering the home inspection field and I have a question regarding LP siding. I am in the Northwest and I understand LP siding was used extensively up here. Does anyone know of any information available that gives the inspector a failure guideline or what to specifically look for when inspecting this product?

Thanks[:-magnify

Look at the drip edges of the both the panel and the lap varieties. If you see swelling or delamination, the stuff is on its way out. It'll look like the edge of a deck of cards that's gotten wet.

From there, the next phase is softening of the material to the point where you can stick your finger through it. Somewhere in there, the mushrooms start to grow.

Once the mushrooms appear, it becomes imperative to remove the product from the house before the fungus can spread to the house’s sheathing or framing.

There are at least three distinct versions of the product. The first generation has square edges and no coating on the backside. Most of it was crap, but now & then I see a house from that period where the siding is still just fine. The second generation has a beveled drip edge (on the lap siding) and a brownish-greenish coating on the backside. It was crap too. The newest version, renamed Smartlap (instead of the old name, Inner-Seal) came out in 1996. It has beveled edges (lap siding only) and no green-brown backing. It’s been behaving very well. They increased the borate content and seriously tightened up the QC at their manufacturing plants.

All of the versions have identical embossing on their faces. You can’t tell them from each other by the grain pattern.

If the house has LP panel siding that's already decayed, tell them not to install the replacement siding over the top of it. The panel siding is the home's sheathing and is supposed to provide shear strength to the framing. If it's decayed, it should go away.

Also remember that there were a whole bunch of similar products in the late '80s & early '90s. While they pretty much all sucked, you don't want to be misidentifying them.

- Jim Katen, Oregon

[hausdok]

Hi Rob,

Jim pretty much covered it. I've got a lot of literature on L-P. I'll try to remember to get some stuff into the downloads section about it within the next few days. If you'd like, shoot me a separate email with your fax number and I'll send some docs your way.

ONE TEAM - ONE FIGHT!!!

Mike

[CHI]

Great! Thanks for the input. I look forward to the wealth of knowledge that I will gain at this site.

Rob