Can hardboard siding just be painted?

Sound hardboard should be kept painted and caulked, and that extends its life. Paint does not fix a board that has already swollen; it will keep flaking at the damaged edge.

How do I know if my siding is hardboard or fiber cement?

Hardboard is lighter and softer; a fingernail or a screwdriver dents a swollen edge. Fiber cement is heavy, hard and does not swell. A contractor can confirm in a minute from a lower board.

Should the sprinklers be changed too?

If a sprinkler head wets the siding, redirecting or replacing it is the cheapest protection for new siding as well as old.

Siding · Older homes

Hardboard Siding Replacement in Cypress

On many houses from the 1980s and 1990s, the lap siding on the upper story, the gables and the back wall is hardboard: wood fiber pressed with resin. Painted and sealed it holds up. Once water gets into an edge, it swells and does not come back.

The Bottom Edge, the Butt Joint and the Nail Hole

Hardboard fails where water sits. The lower drip edge of each board absorbs water if the paint has worn; the board swells, the paint cracks, and the edge flares out or “mushrooms.” Butt joints, where two boards meet end to end, take in water the same way. Over-driven nails break the surface and let it in from the face.

In Cypress the usual accelerant is a lawn sprinkler hitting the wall every morning, or a flower bed built up against the siding. The lowest courses of the back wall, next to the sprinkler heads, are often the worst.

Which Cypress Houses Are Likely to Have It

Hardboard lap siding was era-typical on production homes of the late 1970s through the 1990s across the Houston area, which covers much of Copperfield, Fairfield, Longwood and Coles Crossing. That is a statement about the era, not about any particular house: builders varied, and many owners have already replaced it. The quickest check is to look at a lower board edge on a shaded wall. Copperfield · Fairfield

A Few Boards, a Wall or the House

If damage is limited to a few boards and the rest are sound and painted, replacing those boards is a reasonable repair. The catch is matching: hardboard of the same profile is harder to find than it used to be, and a replacement board of a different material can read differently once painted.

When swelling runs along whole walls, the usual answer is to replace the siding on the affected elevations, or the whole house, with fiber cement. That is also the moment to replace the house wrap and flashing around windows, which have often failed along with the siding. Fiber-cement replacement

What to Ask for in Writing

The replacement material and profile, how much wall will be opened, how rotted sheathing or framing behind the siding will be handled and priced, the trim and flashing plan, and whether painting is included. Then the ACC gets the material and color.

Asked About This in Cypress

Can hardboard siding just be painted?: Sound hardboard should be kept painted and caulked, and that extends its life. Paint does not fix a board that has already swollen; it will keep flaking at the damaged edge.
How do I know if my siding is hardboard or fiber cement?: Hardboard is lighter and softer; a fingernail or a screwdriver dents a swollen edge. Fiber cement is heavy, hard and does not swell. A contractor can confirm in a minute from a lower board.
Should the sprinklers be changed too?: If a sprinkler head wets the siding, redirecting or replacing it is the cheapest protection for new siding as well as old.