Siding

This is the single most misunderstood thing about a wall, and it explains most bad siding work. Siding is not waterproof and was never meant to be. It is a rain screen: it takes the direct hit of wind-driven rain, sheds the overwhelming majority of it, and accepts that some water will get behind it. What keeps the wall dry is the layer underneath — the water-resistive barrier — plus a path for the water that gets past the siding to drain back out at the bottom.

That is why sealing every lap and every gap with caulk makes a wall worse rather than better. A caulked-shut wall still admits water at the top and around openings, and now that water has nowhere to leave. It sits against sheathing and framing. Vinyl siding is deliberately hung loose on its nails and deliberately left open at the bottom of each course for exactly this reason. Understanding what is supposed to be sealed and what is supposed to drain is most of the craft.

Behind the siding sits the water-resistive barrier — housewrap, felt, or a coated sheathing. Its job is to shed anything that gets past the cladding, and it does that only if it is lapped shingle-style, upper sheet over lower sheet, all the way down the wall. One reversed lap is a funnel pointed into the wall cavity.

Openings are where it gets decided. A window or door interrupts the drainage plane, so the barrier has to be cut, folded, and integrated back together in a specific order: sill pan flashing first so anything reaching the rough sill drains outward, then jamb flashing lapped over the sill flange, then head flashing over the top flange with the housewrap lapped over the head flashing rather than under it. Get the order wrong and the flashing directs water into the framing with great efficiency. The other critical detail is kickout flashing where a roof edge terminates against a wall — without it, a whole roof plane worth of water is delivered straight behind the siding at that corner, which is why that spot rots so reliably.

Vinyl

Vinyl is the most installed cladding in the country because it is economical, it never needs painting, and it goes up fast. It handles moisture indifferently — it does not rot and it does not absorb water. The tradeoffs are thermal and impact related. Vinyl expands and contracts substantially with temperature, which is why it must be hung loose rather than nailed tight, and why installation error shows up as waviness in August. Under Texas ultraviolet load, color holds better than it used to but darker colors still fade on south and west walls. It is the material most vulnerable to hail.

Fiber cement

Fiber cement is a cement, sand, and cellulose composite. It is dimensionally stable across temperature swings, so it does not oil-can or wave in the heat. It is non-combustible, which matters more every year. It holds paint exceptionally well because the surface is porous and stable, and factory-finished products carry long finish warranties. Against hail, it behaves differently from vinyl: instead of cracking through and shattering, it tends to chip, crack locally, or take a dent at the impact point, and single damaged boards can usually be cut out and replaced. It is heavy, it requires specific cutting and fastening practice, and its butt joints and cut edges must be primed and detailed or the board wicks water.

High-end composite

Engineered wood and polymer composites aim at the appearance and workability of wood with better moisture behavior. They cut and fasten like lumber, take deep wood-grain texture, come in long lengths that reduce joints, and weigh far less than fiber cement. They are the usual pick where an owner wants a real wood look without the maintenance cycle of real wood.

• Lap — horizontal courses, each overlapping the one below. The default, available in every material, and the most forgiving of the three at shedding water.
• Shake and shingle — staggered or straight-coursed panels used on gables, dormers, and accent walls. More joints per square foot, so flashing and course alignment matter more.
• Board-and-batten — vertical boards with narrow battens over the joints. Strong architectural look, but the vertical orientation means water runs along seams rather than across them, which puts more weight on the barrier behind and on the base detail.

Hail damage on walls is real and frequently missed, because adjusters and owners both look up. It concentrates on the elevation the storm drove into, so a house can have one badly damaged wall and three untouched ones.

• Vinyl cracks and punches through, especially when it is cold and especially on aged material that has lost plasticizer. Look for holes, star-pattern cracks, and chipped bottom edges on the impacted elevation.
• Fiber cement chips and cracks at the point of impact rather than shattering, and the damage often shows as removed paint and a small crater rather than a hole.
• Composite dents and bruises, sometimes with the finish broken at the impact point while the board stays intact.
• Aluminum and steel trim, fascia wrap, and window wrap dent visibly and are often the clearest evidence anywhere on the house that hail of a given size actually fell.

If a storm damaged your siding, it very likely damaged the roof, the gutters, and the window wraps as well. CMAC documents all of it in one inspection and handles the claim conversation with your carrier.