Often referred to as Georgia-Pacific®, Weyerhaeuser® or Masonite® siding, this type of siding is made by numerous different manufacturers. Each company's fiberboard is made in roughly the same manner and tends to have the same problems.

After this siding has been installed for some length of time it tends to expand slightly. This causes the area around the nail heads to become damaged, this allows moisture to penetrate the board and deteriorate the paneling. 

As the moisture level rises, the board’s edges tend to expand breaking the paint, which, in turn, allows rainwater to be absorbed causing a breakdown of the glue and deterioration of the product.

Hardboard planking also tends to shrink and swell along its length, breaking the seal where the boards’ joins have been caulked during installation, leaving them vulnerable to water penetration.

It is very important that the caulking on this hardboard type siding is maintained in good condition. Regular repainting of the home is strongly recommended even though the previous paint may appear to be in good condition.

It may be possible to slow down the deterioration of this siding by regular painting and caulking; however, home owners should be aware that there will be problems with their siding in the future.

Identifying Various Siding Markings

Identifying the type of siding you have is the hardest part of the entire process. 

To find the markings:

·         Pull a board off the house and look at the back. Look for markings and notice the color and texture.

·         Go to an unfinished part of the house like in a garage or attic. Pull back the protective tar paper and look for markings.

·         Look for samples left in the attice or in the rafters of the garage.

·         Besides finding the manufacturer's markings on the back (see pictures below) or identifying the pattern, you can also match the American Hardboard Association codes stamped on the boards. Look for the AHA markings and use the following tables to help you.