How to Prevent Dry Rot: 5 Tips from a Portland Siding Expert

Early detection is key. Make it a habit to visually inspect your siding at least twice a year—once in the spring and again in the fall. Look for:

• Peeling paint or caulk
• Soft, spongy, or discolored wood
• Musty odors near exterior walls

Catching these signs early allows for quick repairs to stop dry rot in its tracks. Check out our video here about how Sister Siding can help with this with our repair-first approach.

Clogged or damaged gutters are a leading cause of dry rot. Overflowing water can seep into siding and trim, creating the perfect environment for fungal growth.

Our Portland climate demands seasonal gutter cleaning, especially after fall leaf drop and heavy winter rains. Ensure your downspouts direct water away from your siding.

Even the smallest gaps can let water in. Around windows, doors, and joints where siding meets trim, use a high-performance, paintable exterior caulk to seal cracks. For added protection, pair this with a weather-resistant exterior paint.

Caulking should be used as part of siding installations and siding repair projects to ensure long-term moisture resistance.

Wood siding is beautiful but can be vulnerable to dry rot if not properly maintained. If you’re replacing or upgrading your siding, consider rot-resistant alternatives like:

• Fiber cement siding (like James Hardie products)
• Engineered wood siding
• Treated wood or composite materials

These materials offer the look of wood with much greater resistance to rot, insects, and moisture.

Dry rot doesn’t just come from rain—it also comes from trapped moisture inside walls. Make sure your home’s exterior systems are working together to breathe and shed water effectively.

This means:

• Soffit and attic vents are clear
• Siding has proper flashing
• Wall assemblies include house wrap and rain screen systems

When we install or repair siding, our team at Sister Siding always checks for proper moisture management to prevent future dry rot problems.

Even the best siding materials won’t protect your home from dry rot if they’re installed incorrectly. Poor installation leaves gaps, misaligned panels, and missing flashing that allow water to seep in—leading to moisture buildup, fungal growth, and ultimately, dry rot.

Hiring a professional siding contractor ensures:

• Proper moisture barriers and flashing techniques
• Correct sealing and caulking around all joints and openings
• Precise installation that prevents water intrusion
• Code-compliant practices and manufacturer warranties

We also wrote this blog on what to look for when hiring a portland siding contractor so you can learn more.

At Sister Siding, we don’t cut corners. Our team is trained to identify problem areas before they turn into costly damage, and we use the right tools, materials, and methods to make sure your siding performs exactly as it should. Quality installation today means fewer repairs

We’re more than just siding contractors—we’re your neighbors, and we care about protecting homes in the Portland area from dry rot and water damage. Whether you need a dry rot inspection, siding repair, or a full replacement, we’ll walk with you every step of the way with honesty, craftsmanship, and integrity.

We also take a “repair first approach,” where we repair what we can and only recommend new installations when it is necessary. Taking a proactive approach to your home’s siding, especially when it comes to dry rot, can save you a lot of money in the long run. As we like to say, “don’t let a simple $250 fix turn into a $25000 repair later on.”

Ready to protect your home? Call Sister Siding today or request your free estimate online. Let’s keep the rot out and the beauty in.