Steven L. Smith, Bellingham, WA Home Inspector (King of the House)


L-P Siding Failure (Bellingham Home Inspector) King of the House

In the 1980's and up to 1995, and even after that,  Louisiana Pacific (L-P) innerseal siding was popular with builders. That was, especially so, true in my corner of the Pacific Northwest.

L-P siding is still available and, whether or not the new variation of the product is much of an improvement over vintage innerseal is up in the air. I see plenty of delamination and decay at newer oriented strand board or OSB sidings such as L-P.

We do know that some problems with the siding involve installation errors but, also, the L-P innerseal product, due to durability issues, was subject to a class action lawsuit. Typical problems with L-P cladding include swelling, fungal growth, delamination, decay, cracking and buckling.  When siding ends up in the condition shown in photos below, all you can do is replace it and hope that sheathing behind the material is not too messed up. If sheathing is damaged, replacement costs will go even higher.

L-P knot, distinctive, on innerseal siding
L-P knot defined. L is blue. P is red

Siding failure -crumbling (two examples)                                             



Steven L. Smith

If you enjoy nostalgia and music of yesteryear, click on Elvis' gold record to visit This Day In History. To explore The Stories Behind The Music blog posts click on the electric guitar. 







Comment balloon 3 commentsSteven L. Smith • June 09 2014 08:24AM


Even after all these years after the settlement has sunset I still an abundance of LP issues. Some look like mushroom farms Steve!

Posted by Paul S. Henderson, REALTOR®, CRS, Tacoma Washington Agent/Broker & Market Authority! (RE/MAX Northwest.) almost 5 years ago

Wow, I would think in your neck of the country, with as little sunlight as you get, that LP would not be a very good product.  I am kind of surprised it was used there.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) almost 5 years ago

Steve, Over here sprinklers can wreck havoc on it. For the most part it tends to fair pretty well here.

Posted by Donald Hester, NCW Home Inspections, LLC (NCW Home Inspections, LLC) almost 5 years ago