That soft area on your deck is not a good sign. It’s probably deck rot. It’s a major safety risk.
Left alone, it can add up to costly repairs or a full deck replacement. Deck rot repair can help address issues before they get out of control.
What Causes Deck Rot?
There’s good news: deck rot is preventable. With proper care and some seasonal maintenance, you’ll keep your outdoor space from needing deck rot repair.
As you know, wood absorbs moisture. Over time, this causes fungal growth like mold and mildew, which leads to deck rot. Fungi thrive in damp conditions with poor ventilation. If your deck is in a shaded area with debris like leaves and grass clippings often getting on it, you can make the issue worse.
Good deck design and planning is the first step to helping prevent fungal growth on your deck.
Start with the Right Materials
If you use a composite wood material like Trex or Timbertech, deck rot repair is a non-issue.
Everybody else is going to want to use pressure-treated lumber. It’s a good choice, but not all pressure-treated lumber is built the same. You’ll need to become familiar with the American Wood Protection Association’s (AWPA) ratings. They provide categories and ratings for the type of pressure-treated lumber you’ll need in every use case in and outside of your home.
Credit: American Wood Protection Association
In the graphic above, you can see how the deck needs boards rated for above-ground use at category 3B or higher. The illustration also shows how to read the information on the board end tag to see if it’s right for your project and is resistant to deck rot.
Varieties like redwood, cedar, or tropical hardwoods, including ipe, offer superior durability. The high initial cost of composite decking materials is justified by their extended protection against moisture and the need for deck rot repair.
Slopes – A Hack for Preventing Deck Rot Pair
Building decks with a slight slope away from the house guarantees proper water drainage. It’s commonly said that a deck surface sloped 1/8 inch per foot keeps water from pooling and helps stop deck rot. It’s a good start, but when it comes to boards running perpendicular to the house or solid decks, you’ll probably need 1/4-inch.
Floating decks with gaps between boards and composite decks typically don’t need slopes at all.
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You can add small shims beneath the joists or use a belt sander to establish a slight angle on decks that were not originally built with this feature. It can be a small adjustment that saves you from a more involved deck rot repair.
Tips to Prevent the Need for Deck Rot Repair
Regular Sealing and Staining
Wood decks require ongoing protection to keep moisture at bay. Apply a high-quality water-repellent sealant, like Thompson’s Water Seal, to your deck every one to three years. Stains serve a dual purpose by providing color while containing sealants that protect against UV exposure and moisture. Use a deck cleaner to remove mildew, dirt, and old finish before sealing. Neglecting this cleaning step results in trapped moisture, which leads to damage that outweighs any potential benefits.
Add Spacing Between Boards
Tight-fitting boards may appear attractive but can create potential issues. Adding space between deck boards, measuring between 1/8 to 1/4 inch, allows for airflow and water drainage. Boards that are too close together capture more water and will most likely need deck rot repair. A circular saw with a guide will help you create wider gaps if your deck boards are too tight. After widening the gaps, it’s crucial to seal the exposed wood surfaces.
Make Sure to Sweep Your Deck
Deck rot really amps up when leaves and dirt get left on the deck. These pockets of debris trap moisture and cause deck rot. Keeping your deck swept and clear is an important maintenance step. During the fall, use a leaf blower or broom to make sure no debris is staying on it.
Inspect corners and stairs carefully and monitor all areas where leaves pile up. Keep your gutters clean, too, so that no water is flowing onto the deck.
Inspect Often, Repair Early
Regular inspections enable you to detect problems early before they spread further. During each season, you should walk across the deck and apply gentle pressure to boards and railings to detect any softness or movement. Remove compromised boards right away, and then apply wood preservatives to nearby areas to prevent further damage.
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Frame Deck Rot Repair
While decks require significant maintenance for their surfaces, many often overlook the fact that the structural framing underneath faces similar deck rot issues. It’s often where deck rot starts. A mirror or physical inspection underneath is required to check joists, beams, and posts for signs of moisture or decay. Ensure that there is ventilation underneath the deck to keep the framing dry. Lattice skirts provide aesthetic appeal but limit airflow through decks, so selecting vented designs is important for proper ventilation.
Flashing and Ledger Board Protection
The ledger board represents a critical area for rot because it connects your deck to your home. The structure faces severe problems when water enters this area. A metal flashing installation is necessary at the junction between the deck and the house to enable proper water redirection. Perform an annual inspection of the flashing to ensure it’s sealed and in good shape. If water pools up behind the ledger board, you’ll need to replace it or fix the flashing.
Use Spacers and Post Caps
Deck posts can absorb moisture from the ground when they are embedded in concrete that lacks proper drainage systems. Post caps, along with bottom spacers, prevent direct wood-ground contact, which allows air circulation and helps prevent fungal growth. Existing posts can avoid moisture exposure when metal bases and plastic spacers are added to prevent contact with surfaces that retain moisture.
Consider a Deck Drainage System
Under-deck drainage systems divert water from the frame and joists for elevated decks. These systems defend wood from needing deck rot repair while producing dry space below decks. Deck drainage systems can be installed on both new decks.
Cold Climates and Deck Rot
Cold climates pose unique challenges. Persistent snow creates saturation in deck boards while ice pushes moisture through existing cracks. Use a plastic shovel to clear your deck as often as possible. Do not use salt-based ice melters because they can harm wood surfaces and cause fasteners to rust. Select pet-friendly and wood-safe ice melt alternatives such as calcium magnesium acetate.
Paint Versus Stain: Know the Difference
Although decking paint attracts some homeowners, it retains moisture beneath its surface when it starts to peel. Stain works better than paint because it goes inside the wood while letting it maintain its natural air circulation. When selecting paint for your deck, choose exterior-grade options that are specifically designed for deck surfaces.
Rust Can Lead to Rot
Your boards won’t remain stable if rusty nails and screws are used to hold them together. As metal corrodes, it undergoes changes in size, which lets water penetrate. To minimize corrosion, select fasteners made from stainless steel or those with protective coatings. Regularly check hardware for rust and replace items that show signs of wear.
Quick Summary
To avoid needing deck rot repair, make sure you follow these maintenance tips. Fungi are the cause of deck rot. Moisture and poor airflow give them a breeding ground. Use the right type of pressure-treated lumber based on the AWPA’s guidelines. Your deck will thank you.
