Inspect, repair, and maintain vinyl, wood, and fiber-cement siding. Spot cracks early and stop water before it gets behind the wall.
Most common. Doesn't rot. Cracks when hit. Fades over decades. Easy DIY repairs.
Classic look. Needs painting every 7–10 yrs. Can rot if not maintained. Repairable.
Hardie Board. Very durable. Fire resistant. Heavier to work with. Pro paint usually required.
Walk all four sides of your home once a year. Take photos of anything that looks concerning. Water behind siding = rot, mold, structural damage. Catching it early is cheap.
Any breach lets water in. Vinyl: spider cracks or broken pieces. Wood: checking (lengthwise cracks), peeling paint (moisture from behind). Fiber cement: chips or cracks at cut ends.
Gently press on siding at various points. Soft or spongy = rot behind it. Pay extra attention near windows, doors, corners, and where siding meets trim — these are water entry points.
The caulk where siding meets window and door trim is the most common water entry point. Look for cracking, gaps, or missing sections. Re-caulk any you find — it's a $10 fix that prevents $10,000 problems.
The bottom edge of siding should be at least 6" above grade (soil/mulch). Siding buried in mulch holds moisture and rots. Rake mulch away from the house base.
Vinyl siding panels snap in and out. A cracked panel can be replaced in 30 minutes with a zip tool and a matching panel. The hardest part is matching the color if your siding has faded.
Take a sample piece to a siding supplier, not a big-box store. Siding suppliers stock hundreds of profiles and colors. Bring the manufacturer name if you can find it (often embossed on the back of a panel).
A zip tool ($10) is a hooked blade that slides along the bottom edge of the panel above your damaged one, unlocking the interlock. Slide it along the full width of the panel.
Once unlocked, flex the panel above up and nail-punch or pry out the nails holding the damaged panel. Note nail spacing (typically every 16" or 24").
Cut new panel to length (10% expansion gap at each end). Slide the bottom of the new panel into the lock of the panel below. Nail through the top nailing hem — nail in the center of slots (allows movement).
Snap the bottom lock of the panel above back over the top of your new panel. The zip tool reversal: work it along to reform the interlock. You're done.
Soft, spongy wood isn't a death sentence for your siding. Epoxy wood filler + a coat of primer and paint is a repair that lasts 10+ years on small to medium rot spots.
Use a screwdriver to probe the soft area. If it's soft only on the surface (1/2" or less deep), epoxy filler is appropriate. If you can push the screwdriver all the way through the board, replace the entire piece. Epoxy won't save structurally compromised wood.
Use a chisel and wire brush to dig out every bit of soft, discolored, or crumbling wood. The repair area should be firm, clean wood. If you leave soft wood under the filler, the rot continues underneath it.
Pour or brush the liquid consolidant into the void and onto the surrounding wood. Let it soak in for 5–10 minutes. This hardens the wood fibers around the damage and bonds the filler to dry wood. This step is what makes epoxy repairs last.
Mix equal parts of the two-part epoxy filler according to directions (usually about a 5-minute work time). Pack it tightly into the cavity — press hard to eliminate air voids. Overfill slightly above the surface.
Epoxy filler is workable for about 15–30 minutes. Shape it close to the final form with a putty knife. After it cures fully (4–6 hours), sand with 80-grit then 120-grit to blend perfectly with surrounding wood. It paints and holds like wood.
Epoxy filler must be primed or moisture will eventually delaminate it. Apply exterior primer, let dry, then apply at least two coats of matching exterior paint. The repair should be invisible.
The gap where siding meets window and door trim is the single most common water entry point on any home. Cracked, missing, or hard caulk should be replaced every 5–10 years.
For exterior use, use paintable polyurethane or siliconized acrylic latex caulk. Never use pure silicone for exterior joints you plan to paint — paint won't stick to it. And never use interior latex caulk outdoors — it fails within one season.
Use a utility knife or caulk removal tool to cut out the old caulk. Remove it completely — applying new caulk over old caulk is the biggest reason exterior caulk fails quickly. The joint needs to be clean, dry, and bare.
Use a wire brush to remove old caulk residue. Wipe the area with a clean rag. Let dry completely — caulk will not bond to a damp surface. On a sunny day, 15 minutes is enough. After rain, wait 24 hours.
Cut the caulk tube nozzle at 45° to a size matching the joint width. Apply in one smooth, continuous bead — start at one end and work to the other without stopping. Hold the gun at 45° and push (not pull) for better joint filling.
Wet your finger with water or use a caulk tool. Drag it along the bead in one smooth motion to press the caulk into the joint and leave a concave, professional surface. Wipe up excess with a damp cloth. Let cure 24 hours before painting.
Pressure washing removes mildew, dirt buildup, and algae that degrades paint and causes moisture problems. Required before repainting. Best done in spring or fall.
Vinyl: 1,200–1,500 PSI, 25–40° tip, hold 12–18" away. Too close or too much pressure can crack vinyl, force water behind panels, or strip caulk.
Wood: 500–1,000 PSI only, 40° tip, hold 18–24" away, always spray with the grain. High pressure on wood raises the grain and causes swelling.
Cover all plants, shrubs, and electrical fixtures. Pre-wet surrounding vegetation with plain water. Close all windows and doors. Check that all vents and openings are closed to prevent water intrusion.
For mildew and stubborn grime, use a pressure washer's soap dispenser or apply siding cleaner by hand with a soft brush. Let dwell for 5–10 minutes — don't let it dry on the surface.
Always work downward — never spray upward into the seams between siding courses. Spray at a slight downward angle following the overlap direction. Work in 4-foot wide sections to stay organized and ensure even coverage.
Switch back to plain water. Rinse from the top down, chasing the dirty water. Multiple passes may be needed near the foundation. Allow to dry fully (48 hours) before any painting or caulking work.