How to Clean Every Type of Outdoor Flooring—Plus, the Best Products to Use
Give your outdoor space a good clean, no matter the season.
A gleaming deck or patio is a delight, but it's not surprising if, after years of constant exposure, yours begins to look a bit worn and stained. Whether your beloved outdoor space is made of wood, brick, stone, concrete, or composite, routine maintenance and an occasional cleaning will ensure it always looks as good as new.
Basic Care Tips
To clean your outdoor floors, use a broom made for outdoor surfaces, and sweep as often as needed to eliminate dust and debris. Hose the entire area down occasionally to remove substances that stain—you'll want to start with the gentlest cleaning methods. If these don't work, then try products with strong chemicals—but, before you work with cleaning products or apply stains or sealants, it's essential to read all directions carefully. Use only natural-bristle or plastic scrub brushes. Metal brushes can scratch surfaces easily and cause staining. Saturate surfaces with water before using cleaning solutions to avoid staining. Never let cleaning solutions dry on surfaces—cool, overcast days are best for this task. Be certain to rinse all cleaning solutions thoroughly from surfaces with plain water. Finally, be sure to avoid power washing, except on concrete. It can save time, but it can also etch some types of brick and soft stone, damage mortar joints, and splinter wood.
Brick comes in so many washes and colors, but keeping it clean can seem overwhelming. "Using a pressure washer to clean brick makes the daunting task quick and easy with long-lasting results," says Gina Perry, senior merchant for cleaning & convenience at The Home Depot. "The high-pressure hose blasts grit and grime from brick, stone, and concrete so you can clean not only your brick but also your driveway and sidewalk." Perry recommends Ryobi's Electric Pressure Washer ($99, homedepot.com) and Zep's Driveway and Concrete Pressure Wash Cleaner ($9.98, homedepot.com). The pressure washer comes with three quick-connect nozzles for cleaning a variety of surfaces, including brick. Perry notes that you'll need to repair any cracks in your bricks or mortar before using a pressure washer on the required surface, and "to make sure to cover and protect light fixtures, electrical outlets, and jacks with a waterproof material as you don't want water to penetrate and harm them."
Using a surface cleaner attachment or high-pressure nozzle, clean your bricks along the path in one direction as you go, says Perry. "Try to spray in horizontal strokes over a three- or four-foot-wide area at a time," she says. "Once the job is complete, wait 24-48 hours and spot-treat any leftover stains that your pressure washer left behind—things like mildew or masonry bloom." She suggests using water and cleaner with the sprayer to remove those stains and clean them up. For more stubborn stains, she says to use cleaner and scrub with a wire brush. "If you're dealing with mildew and mold, use equal parts chlorine bleach and water to make short work of them," she says. "Dilute an acid-based masonry detergent to tackle rust, following the manufacturer's instructions carefully. Rinse thoroughly and let dry."
This is a durable, forgiving material, but strong acids may damage concrete. Even a weak acid solution can roughen the surface if it is left on for any length of time. To remove oil that has leaked from a car's engine, blot with paper towels, then cover the spot with cat litter, and leave overnight. Remove the litter, and repeat until oil is no longer being absorbed. If needed, follow with a poultice: Mix one part trisodium phosphate with six parts water. Apply, and leave on for 24 hours. Scrub and rinse with plain water. To remove grease caused by food, scrub with a household scouring powder. To remove moss and organic matter, apply a solution of one part chlorine bleach to 10 parts water.
To give it a good deep cleaning, in a bucket, mix together hot water and an all-purpose household cleaner or a concrete cleaner. Use a stiff-bristle broom or brush to scrub the surface thoroughly. You can also pressure wash concrete, says Perry. "The high-pressure hose blasts grit and grime from brick, stone, and concrete so you can clean not only your brick but also your driveway and sidewalk."
As far as maintenance is concerned, sealing concrete will make it stain resistant (but not stain-proof) and easier to clean. If you opt to seal, choose a penetrating concrete sealer. A clear, silicone-based water-repellent sealer is a good choice if you want to maintain the appearance of the concrete. If you want to do more than preserve the surface—for example, enhance the color (often desirable with exposed aggregates) or add gloss—choose an acrylic-based sealer. Don't use deicers that contain ammonium nitrate or ammonium sulfate, which can destroy concrete. Never let fertilizer sit on concrete; if it gets wet, it can leave stains.
All wooden surfaces eventually turn gray from sun exposure. North American woods, including Southern pine (which is often pressure treated), cedar, and redwood, benefit from regular sealing; this can help prolong the rich look of the wood. Tropical woods, such as ipe, Bangkiria, and mahogany, are dense and oily and usually don't need sealing. Perry says, "Periodically rearrange your outdoor furniture, including planters, toys, and grills, to prevent sunlight from causing mismatched color patches as well as water gathering beneath them."
North American woods need to be sealed yearly to protect them from the elements. Perry recommends BEHR's Cedar Naturaltone Semi-Transparent Waterproofing Exterior Wood Stain and Sealer ($34.98, homedepot.com), as it's an all-in-one wood stain and sealer with complete weatherproofing protection from the elements. To remove mold and rust stains from your wood floors, Perry says to make a more potent cleaning concoction. "When mixing a cleaning solution for extremely dirty wood, consider a lower proportion of water for a more concentrated cleaner," she says. "This may be especially effective for long-neglected decks."
Composite decking materials are made of wood and plastic (sometimes recycled grocery bags or milk jugs). Manufacturers typically do not recommend painting, staining, or sealing composite surfaces. The best way to combat mildew and other stains is to keep the deck clean with regular use of a broom and a hose. Like regular wood, composites can become moldy and develop tannin stains. A deck cleaner that contains sodium hypochlorite should remove mold; one that contains oxalic or phosphoric acid will remove tannin stains and get rid of dirt and rust. Most composites can be deep cleaned with deck cleaner containing phosphoric, oxalic, or hydrochloric acid, or sodium hypochlorite, and a stiff-bristle brush or broom. Consult the composite manufacturer. It's important not to pressure wash this type of material, notes Perry. "Do not use a pressure washer on a composite deck, as it can damage the decking," she says.
Patio stone can be divided into two categories. Siliceous stone (granite, slate, sandstone, brownstone, and bluestone) is hard and durable. Calcareous stone (marble, travertine, and limestone) is more delicate and porous, so it is susceptible to stains. To tell which kind you have, put a drop of white vinegar in an inconspicuous spot. If it fizzes, the stone is calcareous. Use a pH-neutral stone cleaner, and scrub with a soft-bristle brush or broom. Avoid household detergents, which tend to be too acidic or too alkaline. Repeated use of them can erode calcareous stone and dull the polish on siliceous stone.
To remove stains, use a stone poultice. Read the label to be certain you're choosing the right stain remover for your needs. When cleaning siliceous stone, you can boost the power of a stone poultice by adding a little all-purpose household cleaner, as long as it doesn't contain chlorine bleach. To remove moss and organic matter from siliceous stone, use a stone cleaner that has phosphoric acid. For calcareous stone, choose a nonacidic algae remover.
Weathering and the sun will fade most stains over time, but they fade the luster of surfaces, too. A stone enhancer will bring a more saturated look to the stone, particularly to slate and tumbled marble. If you opt for an enhancer, choose one with a built-in sealer to add stain resistance. Calcareous stone surfaces in high-traffic areas will benefit from sealing to aid stain resistance. As always, read labels to be sure the sealer is designed to protect against the stains you're likely to encounter. Reapply it every three to five years.