How can I tell hardboard siding from fiber cement?

Press a thumbnail into a lower edge. Hardboard that has taken on water feels soft or swollen, while fiber cement stays hard. Fiber cement boards are also much heavier, and a broken fiber cement edge looks gritty and gray rather than fibrous.

Is my house old enough for lead paint rules?

If it was built before 1978, treat painted siding as possibly containing lead until it is tested. In Oregon, work that disturbs 20 square feet or more of painted exterior on such a house requires a contractor with a Construction Contractors Board lead-based paint renovation license.

Can permit records show what siding was installed?

Rarely for siding alone. Replacing or repairing siding is generally exempt from a building permit, so there may be no record of it. The year built in county property records is a better starting point.

How long does siding last in Oregon?

There is no dependable published lifespan for siding in Salem's conditions. How long a wall lasts depends mostly on how the siding was installed and kept up, including flashing, clearances, the barrier behind it and the paint. Manufacturers' warranties describe what each maker covers, not how long a particular wall will last.

What Siding Do I Have? How to Identify It by Era

Start with the year the house was built, or the year it was last re-sided, and then look closely at a lower board and at any damaged or cut edge. In the Salem area, where the median home was built in 1980 (1981 in Keizer and 1978 in Silverton, according to Census ACS 2020-2024 estimates), siding from the 1980s and 1990s is the most useful to identify. Two products used then, hardboard lap siding and LP Inner-Seal OSB siding, were the subject of class-action settlements that have since closed, and both fail in ways that decide between repair and replacement.

Step 1: When did the siding go on?

Year built. County property records list it: Marion County for most of Salem, Keizer, Silverton and Stayton, and Polk County for West Salem, Dallas, Monmouth and Independence.
Year re-sided. Harder to pin down, because replacing siding on its own is generally exempt from a building permit and may leave no record. Sale disclosures, old invoices or a previous owner are better sources.

Three dates are worth holding onto:

Before 1978: painted siding may carry lead paint, and lead-safe rules apply to larger jobs.
1980 to January 1998: the installation window covered by the Masonite hardboard siding settlement.
Before 1996: the installation window covered by the LP Inner-Seal OSB siding settlement.

Step 2: What does it look and feel like?

Hardboard lap siding (often called Masonite)

Long lap boards, smooth or embossed with a wood-grain pattern that repeats along the wall. Where paint has failed, the lower edges swell, flare or go soft, and a broken edge looks like pressed fiber. Masonite is one brand; other companies made hardboard siding too. See swelling hardboard or OSB siding.

OSB lap siding (LP Inner-Seal and others)

Similar lap boards made from wood strands bonded with resin. At worn or damaged spots you can see the pattern of flat strands under the paint, and edges swell the same way hardboard does. The LP Inner-Seal settlement covered siding installed before 1996.

T1-11 plywood panels

Sheets of plywood, commonly 4 by 8 feet, with vertical grooves cut into the face. The layers of veneer show at cut edges, and damaged panels peel apart, usually starting at the bottom edge and at horizontal seams. In Salem, replacing T1-11 that also serves as the wall’s structural sheathing needs a building permit. See T1-11 siding damage.

Cedar and other solid wood

Real grain that changes from board to board, with knots and the texture of the saw. Shingles are sawn and even; shakes are split and rough. Soft spots in solid wood are rot, not swelling. See cedar and wood siding and dry rot in siding and trim.

Vinyl

Thin, hollow panels that lock into one another, finished around windows and corners with plastic channels and posts. The color runs through the material, and damage shows as cracks, holes or rippled panels rather than rot. See vinyl siding.

Fiber cement

Rigid, heavy boards, panels or shingles, smooth or embossed. A broken or cut edge looks gritty and gray, like cement, and the boards stay hard when pressed. See fiber cement siding.

Engineered wood

Newer lap siding made from treated wood strands or fibers, such as LP SmartSide. It can look a lot like hardboard from the street, so the year it went on matters; LP SmartSide is a different product line from the LP Inner-Seal siding in the settlement.

Step 3: Check a spot most people never look at

Look where a board end or bottom edge is exposed: behind a downspout, at the bottom course near the ground, beside a foundation vent, or at a corner where trim has come loose. The back of a loose board sometimes carries a maker’s stamp. On a house built before 1978, avoid scraping or prying painted siding yourself; a contractor can identify the siding without disturbing old paint.

Why does the siding type matter?

Permits. In Salem, siding alone is permit-exempt unless the wall must be fire-resistive, but sheathing repair needs a permit, and so does replacing T1-11 that is also the sheathing. See do you need a permit to replace siding in Salem?
Repair or replace. Discontinued hardboard can be hard to match board by board, which pushes some jobs toward siding replacement.
Lead-safe work. Pre-1978 paint changes how a job is set up and who can do it.
Claims. Knowing the product saves time chasing settlements that have already closed.

How long does siding last?

No dependable published figure covers siding lifespans in Salem’s conditions, so this site does not give one. Installation and upkeep decide most of it: a wall with sound flashing, the right clearances, a water-resistive barrier and maintained paint outlasts the same siding without them. Manufacturers’ warranties vary by product and describe what each maker covers, not how long a particular wall will last.

If you still cannot tell what is on your house, say so on the request form. Request a siding quote and we connect you with an independent siding contractor who covers your ZIP code. The contractor can identify it on site.

This page is general information, not professional advice about your specific situation. Have it assessed by a qualified professional before making decisions.