6 Best High Performance Sandpaper Grits For Deck Refinishing

A weathered deck is often the most neglected feature of a small home, yet it serves as the primary outdoor living space for those in compact dwellings. Neglecting the surface leads to rot, splinters, and an eventual loss of structural integrity that threatens the entire build. Proper refinishing is not just an aesthetic choice; it is a critical maintenance task that secures the longevity of your investment.

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Diablo 36-Grit SandNet: For Aggressive Stripping

When a deck is coated in thick, peeling layers of old paint or heavy oil-based stains, standard sandpaper clogs within minutes. The Diablo 36-Grit SandNet acts as an industrial-grade solution, utilizing a mesh design that allows dust to pass through rather than building up on the surface. This prevents heat friction and ensures the grit remains sharp enough to chew through the toughest layers of finish.

This is the go-to choice for anyone dealing with long-term neglect or stubborn, multi-layered coatings. While aggressive, it is essential for bringing the wood back to a blank slate without wasting hours on clogged, ineffective sheets. If the primary goal is total restoration, this product is the necessary starting point.

3M Pro Grade 60-Grit: To Level The Surface

After the heavy stripping is complete, the wood surface will likely show deep gouges and uneven patches. 3M Pro Grade 60-Grit provides the ideal balance of material removal and surface smoothing needed to transition from heavy demolition to refinement. It levels out the “valleys” created by the 36-grit pass, preparing the grain for more precise work.

This grit level is specifically for the user who demands a flat, consistent surface before applying any stain. It is robust enough to handle residual stubborn spots but gentle enough to stop the aggressive scarring left by lower grits. Choosing this mid-range grit is the most effective way to ensure the deck does not look patchy once the finish is applied.

Diablo 80-Grit SandNet: Your Main Workhorse Grit

The 80-grit stage is where the transformation from “rough lumber” to “finished deck” truly begins. By using the SandNet design again, the user avoids the common pitfall of material clogging, which is crucial as the wood fibers begin to smooth out. It effectively removes the scratches left by the 60-grit paper while maintaining enough bite to open up the wood pores.

This is arguably the most important stage of the entire sanding process. If the 80-grit pass is rushed or skipped, the stain will soak in unevenly and show streaks. For a professional-grade outcome that mimics high-end deck installations, dedicate the most time and effort to this specific step.

3M Pro Grade 100-Grit: Perfect Pre-Stain Finish

For many, 80-grit feels like the end of the line, but a 100-grit pass is the secret to a high-end, smooth-to-the-touch finish. 3M Pro Grade 100-Grit refines the surface without closing off the wood pores too tightly. This is vital for ensuring that stains and sealers can penetrate deeply for long-term protection against the elements.

This grit is specifically recommended for softwoods like cedar or pine, where over-sanding can cause the wood to burnish and repel liquids. By sticking to 100-grit as a final pass, the finish remains absorbent while losing that “fuzzy” texture common with untreated wood. It is the mandatory final step for those who want their deck to look as good as it feels under bare feet.

Gator 220-Grit Paper: For Between-Coat Sanding

Refinishing a deck often involves multiple coats of high-performance exterior stain or clear coat. Between these applications, the wood grain tends to “raise” or fuzz up as it reacts to the moisture in the product. Gator 220-Grit provides a light, non-aggressive abrasion that knocks down these fibers without removing the underlying finish.

This step is strictly for the perfectionist. If the goal is a furniture-grade finish that feels silky smooth, this is non-negotiable. Use it lightly between coats, and always wipe away the dust thoroughly with a tack cloth before applying the final layer.

3M Sanding Sponge: For Rails and Detail Work

A large orbital sander cannot reach the tight corners, banisters, or decorative rail carvings found on most decks. A 3M Sanding Sponge adapts to these contours, providing uniform pressure where mechanical sanders fail. Its flexibility allows the user to follow the curves of spindles without creating flat, ugly spots.

Avoid the temptation to hand-sand rails with folded flat sandpaper, as it will never reach the deep crevices and will likely result in uneven wear. The sponge acts as a contouring tool, making it the most efficient way to achieve a uniform look across the entire structure. Invest in a few different shapes if the deck has complex architecture.

Choosing Your Sander: Orbital vs. Drum

The debate between an orbital sander and a drum sander comes down to the scale and condition of the deck. An orbital sander is easier to control and less likely to cause permanent damage, making it the superior choice for most homeowners and DIY enthusiasts. However, a drum sander is essentially a rental-only tool meant for massive, flat, and heavily damaged expanses.

• Orbital Sanders: Best for control, tight spaces, and preventing deep swirl marks.
• Drum Sanders: Powerful but unforgiving; one second of hesitation can result in a permanent trench in the wood.

Unless the deck is exceptionally large or the surface is severely cupped, stick to a high-quality orbital sander. The time saved by a drum sander is rarely worth the risk of ruining the wood surface entirely.

How Much Sandpaper Do You Really Need?

Overestimating the amount of sandpaper is a common mistake that leads to unnecessary waste, but running out mid-project is a workflow disaster. A general rule of thumb is to calculate the total square footage of the deck and plan for at least three to four changes of each grit level. Rough, splintered wood consumes sandpaper far faster than smooth, flat boards.

Always keep extra packs of 80-grit on hand, as this is the grit used for the longest duration of the project. If you are working on old, painted, or weathered wood, double the amount of 36-grit sheets in the shopping cart. It is better to have an unopened pack to return than to interrupt a project to drive back to the store.

Deck Sanding Safety: Dust Splinters & More

Safety is often overlooked, but sanding generates massive amounts of fine particulate matter that is dangerous to inhale. A high-quality N95 respirator is essential, as old deck coatings may contain lead or harsh chemicals from decades past. Never attempt a sanding project without eye protection, as flying splinters are a constant risk.

Furthermore, consider the environment around the deck. Ensure that children and pets are kept away from the dust, and seal off nearby windows to prevent the fine particles from migrating into the home. Sanding is a messy, intrusive task; plan the workspace layout with the assumption that everything within twenty feet will eventually be covered in fine wood dust.

Pro Sanding Tips to Avoid Common Disasters

The most common disaster in deck refinishing is creating “swirls” or “waves” by pushing too hard on the sander. Let the tool do the work; the weight of the sander is usually sufficient to engage the grit. If the sander requires extreme pressure to remove material, the sandpaper is likely clogged or the grit is too fine for the task.

Always sand in the direction of the wood grain whenever possible, even with orbital sanders, by moving the machine slowly in straight, overlapping rows. Finally, never finish the sanding process and wait days to apply the stain. Wood begins to oxidize and absorb moisture as soon as it is exposed; apply the finish as soon as the surface is clean and dust-free to guarantee the best possible bond.

Refinishing a deck is a labor-intensive project that rewards patience and the correct selection of materials. By respecting the sequence of grits and prioritizing a clean, smooth surface, you turn a weekend of hard work into years of durable, beautiful outdoor living space. Proper preparation is the only shortcut to a finish that truly lasts.