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Exterior Maintenance

Sealing pressure-treated wood

You should always seal pressure-treated wood. Do it as soon as the lumber is dry.

This wood is treated to resist rot and insects, b ut it is not resistant to moisture and sun damage. By applying sealer, you can prevent the penetration of moisture and stop cracks, swelling, and splits. By using pigmented stain/sealer, you can also slow the sun damage that would turn the surface gray.

To determine when to apply the sealer or sealer/stain, place a few drops of water on the wood. If the water is quickly absorbed, the wood is dry and ready to be sealed. If the water beads up on the surface, the wood is still too wet to seal.

Often, pressure-treated wood is wet because it is processed quickly from the tree to the yard and is stored outside. It may take several dry months for the wood to dry out.

You can also consider using a sealer designed to be applied immediately to damp, newer wood. Select a quality sealer made for pressure-treated wood, and follow the specific instructions.

When sealing, be sure to use a high quality sealer, not a cheap stain. You will need to repeat the treatment every few years. Sealing is a must to prolong the life and appearance of the wood.

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Sealing a cedar deck

Before sealing a cedar deck, clean it. Choose a cleaner that matches the brand of finish you plan on using. You can also use Mex, Spic and Span, or Soilax. If there are dark gray mildew stains, add laundry bleach to the solution.

Pressure washing is a good option, but you need to be careful, because cedar is soft and can be damaged by strong spray. I firmly believe you also need to scrub the deck with a stiff brush for a good cleaning. Use a deck brush on the end of a 6-foot pole so your shoulders and legs can boost the scrubbing motion. Rinse well and allow the deck to dry for several days.

I recommend a stain and sealer combination specifically designed for the horizontal surfaces of a deck. Cedar or pressure-treated wood will discolor with age, and a finish with a slight tint can restore a pleasant natural-looking color. A finish with a color tint will also last longer because it more effectively reflects the sun’s ultraviolet rays.

You know it is time to refinish a deck when the wood looks worn, dirty, and lackluster. Another way to tell is to place a few drops of water on the finish. If the water beads up, you don’t need new finish. If the water flattens out and quickly soaks into the wood, it is time to refinish. You need to refinish every two years if you use a high-quality product.

I don’t recommend spraying on a sealer/stain. I believe you need to brush the finish into the pores and cracks of the wood. You can spread the finish with a sprayer, b ut you still need to brush it in.

Don’t use a regular brush. Buy a "rough surface brush." It looks like a thick scrub brush with paint bristles. You attach the brush to a broom handle. Working from a standing position, you scrub stain into the wood. You will find that the rough surface brush holds a tremendous quantity of finish. You can apply a uniform coat of finish very quickly.

Don’t apply a thick coat. The finish must soak into the wood. It should not dry as a thick surface coat that can peel and be damaged easily.

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Cleaning the cracks between deck boards

When you’re cleaning or preparing to refinish a wood deck, you may notice dirt and other debris stuck between the deck boards. You can easily remove this material with an old hand saw. You literally saw the dirt out of the groove and increase the spacing slightly as you saw. This will ruin the handsaw, so don’t use your good one.

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Patching rotted wood

Wood rot on windows, doors and frames can be a big problem. If you just pain t over the rotten wood, the surface looks poor and continues to deteriorate. For frames, trim, doors and windows that are expensive to replace or difficult to match, patch the wood with epoxy filler.

Several types of fillers are available. I like to compare them to Bondo, which many of us used for car body repair when we were kids. Bondo was an epoxy patch for metal that could make the surface look like new.

For wood repair, you need to remove most of the soft or "punky" wood. The remaining soft wood can be solidified with a liquid consolidant. Then you patch the surface with an epoxy patch. The patching material can be the consistency of stiff putty or almost a liquid, depending on the type of product and the mix.

All epoxy products consist of a two-part mix. You add hardener to a base product and mix thoroughly. The product cures through a chemical reaction. Setting time depends on the hardener used and the am bient temperature.

You can actually make a wood or cardboard "form" and pour or shape the patch to almost any contour. Once the product is cured, you sand and file it to a precise shape, surface-finish as needed, then stain or paint.

Epoxy is great for repairing wood surfaces. When used properly, it can restore structural integrity.

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Cleaning and/or repainting metal siding

Metal siding on a home’s exterior eventually fades and discolors. Ultraviolet rays from the sun, airborne pollutants, rain, and other elements take their toll. The finish chalks, fades, and becomes porous, allowing dirt to penetrate the surface. In damp areas, mildew forms, discoloring the siding. Cleaning and/or repainting makes the surface look like new.

You may find that a thorough cleaning is all your siding needs. Clean the siding with detergent and laundry bleach. The detergent washes away dirt, grime and chalking, and the bleach removes dark mildew stains. For detergent, use either siding cleaner available in hardware stores, or a Spic and Span type cleaner. If your siding is mildewed, add bleach to the solution.

My aluminum siding wash formula combines:

  • 1 gallon of hot water
  • 2 cups Soilax
  • 1 cup Tide

Scrub the siding with a soft brush or sponge and rinse well. On many parts of the siding, you can use a diluted solution with more water.

This formula works great on aluminum and will also work well on vinyl siding. Or you can use any easy-to-rinse detergent like Spic and Span, 409, or Fantastic. Just soak the stains with the solution and then scrub with a soft brush or sponge. Rinse well.

To prevent staining, wash from the bottom up. Wet the siding with the hose, and apply cleaning solution liberally with a brush. I like to use a soft automotive brush on a 6-foot pole, applying cleaning solution with the brush from a pail. You might have to let the detergent solution sit on the siding for a few minutes, but don’t let it dry on the siding. Rinse areas as you wash. For larger jobs, apply the detergent with a garden sprayer and then scrub with a soft brush.

In areas with extensive mildew, try Jomax, a concentrated mold and mildew remover. Mix 1 pint of Jomax with 3 pints of laundry bleach and 2 gallons of water. Apply with a garden sprayer per the label instructions. After 5 minutes, rinse off the solution. For heavy stains, scrub lightly. I’ve tried this, and it works just great.

A few more tips from my recent experience. Jomax eliminates most scrubbing when removing mildew stains. To apply it, I attached a soft brush to a long handle that could be extended to almost 12 feet. Though a little harder to control, it eliminated using a ladder in many areas.

The soft, semicircular brush was designed for washing trucks. It was great and could be used at almost any angle. I also used a soft deck-cleaning brush on a 6-foot handle for much of the scrubbing.

Follow all safety precautions for any cleaners you use. Try to avoid working from a roof; it can be slippery, and you could lose your footing.

Cleaning may restore the siding’s natural color so that repainting is not necessary. If the surface is dull and faded, you might also apply a coat of Armorall or Penetrol to restore the gloss and color. Test in a small area first.

If repainting is in order, you have already prepared the surface with a good cleaning. Next, prime bare spots and corrosion with a solvent-based exterior primer. On aluminum siding, corrosion appears white and should be removed and primed. Sever ely chalked surfaces must be primed.

For a top coat, select paint specifically designed for metal siding, or top quality 100% acrylic paint. A quality paint product can last well over 10 years on metal siding.

If the siding on your house is in really bad shape–for instance, if the paint is peeling off-contact the manufacturer of the siding. You may need to check with the original builder or a siding installer to discover the brand and type of siding on your home. Many manufacturers will stand behind their products

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Removing stains from vinyl siding

Unfortunately, petroleum-based products like heating fuel oil can permanently stain vinyl siding. You can’t hurt the siding by trying to clean it, but you may dull the sheen with aggressive scrubbing and strong solvents.

According to the Vinyl Siding Institute, for fuel oil stains you can try Fantastic, Lysol, Murphy’s Oil Soap or Windex. Scrub the area, allow the cleaner to soak into the surface, and scrub some more. The institute also recommends Soft Scrub.

If those cleaners fail to remove the stain, try a solvent–mineral sprits, naphtha, or auto tar remover. Use a soft cloth to apply the solvent. Avoid tarnishing the area by using too much pressure. After removing the stain, rinse with water.

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Discouraging woodpeckers from pecking cedar siding

Homeowners in rural areas sometimes find that woodpeckers go after their cedar siding–even pecking all the way through to the insulation. Why do they do this, and how can you discourage the habit?

Law in many areas protects woodpeckers. They are great at reducing the bug population. They peck at wood to find bugs, and they bore holes to attract more bug "residents." They also peck loudly to define their territory.

I have heard of two methods that can deter woodpeckers from making swiss cheese of your siding.

Try scaring them away with something that moves or makes noise, such as a wind sock, or aluminum pie tins hung from fishing lines. Strips of thin black plastic, 3 inches wide and 3 feet long, may also work.

Distract the woodpecker from the problem area by fastening a block of suet (in a wire basket) to the siding. The woodpeckers love it, and they stop bothering the siding.

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Renew rusty wrought iron railings

Wrought iron railings can rust after years of exposure to harsh weather. You must get rid of the rust before repainting. Try a product like Rust- Oleum Rust Reformer.

First, you will need to remove flaking paint and rust, but not all the way down to bare metal. A wire brush or abrasive pad works well, or try a round wire brush attached to a drill.

After removing surface rust, clean the surface with detergent and water to remove oil, grease and dirt. Let dry completely. Apply the milky white Reformer with a brush or pad. The product will dry to a black finish in about 15 minutes.

For a finish coat, wait four hours, then apply an oil-based enamel. Some products, including Rust Reformer, suggest applying several coats of reformer for a final flat black finish.

This type of product eliminates the need to remove rust down to bare metal. I also believe an oil-based finish coat will work better than latex on exterior metal.

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When exterior varnish peels…

Ultraviolet (UV) rays from the sun deteriorate the cellular structure of the wood, turning it gray. This can happen right through clear finishes, and it is the reason exterior varnishes fail. Treatment with a pigmented stain or a UV protection product can solve the problem. Eventually, all untreated wood left in the sun will turn gray.

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Broken chimney cap

After years of harsh weather, the mortar around the tile of a chimney top (the mortar wash cap) begins to crack. You should caulk the cracks to keep water out of the masonry and prevent extensive damage from freeze/thaw cycles over the winter. When water is trapped inside masonry, freezing literally breaks the chimney apart.

If the cracks are small, they can be sealed with a silicon or masonry caulk. The best caulk to use is a urethane or one-part epoxy.

Clean the cracks with a brush or air spray and fill the cracks with caulk. The caulk is a temporary fix that’s only appropriate if the cracks are small. You should recheck the chimney cap each year.

A more long-lasting fix is to remove the mortar wash cap and replace it with poured concrete. The concrete cap should be 4 inches thick and reinforced with steel bars and mesh. The edge of the cap should extend at least 2 inches beyond the sides of the brick. Ideally, a small groove will be cast under the edge of the cap to channel water away from the brick.

The concrete mix should be specially formulated to withstand weather extremes and moisture. The cap s hould have expansion joint material around the chimney flues. After the cap is cured, these joints should be sealed with caulk.

Pre-cast caps are also available in various sizes.

Most major chimney repairs are best left to professional masons or certified chimney sweeps.

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Quick patch for rain gutters

For quick repair of small holes in the rain gutters, try gutter repair or flashing tape. It’s available in most hardware stores and is manufactured by several companies. This thick aluminum foil tape uses a mastic type adhesive that’s almost like thick tar. The tape comes in short rolls either 2 or 3 inches wide and costs just a few dollars.

To repair the gutter, clean away debris with a wire brush. Wash the area. Once it’s dry, apply the tape, rubbing it well into the hole. The aluminum facing on the back side allows you to rub the tape securely onto the gutter. The foil also protects the patch from sunlight. The adhesive of the tape is thick enough to fill small holes and seams. This repair can easily last several years.

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Tightening loose rain gutters

Most gutter manufactures provide several methods to hang gutters. During home construction, the quick and cheap method of hanging rain gutters involves nailing them to the fascia board with large spikes. Unfortunately, these large nails often become loose. You can replace them with large screw/nails called Gutter Screws from Fasten Master.

You could also replace the nails with a metal bar or strap hanger suited to a remodeling application. The hanger still fastens to the fascia, but several smaller nails are used. The strap stretches over the gutter, securing the outer edge.

To check the specific installation techniques for your gutters, contact the manufacturer or a local distributor or retail outlet.

Another option–one that’s appropriate in new construction or when replacing the roof–is to fasten a strap hanger to the roof sheathing under the shingles.

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Why roof shingles get black streaks

If your home has light-colored shingles, you may see bla ck streaks on them, especially on the north side. The problem is caused by mildew or fungus growth. There is less sunlight on the north side, so the roof stays damp. Mildew loves a damp surface.

The best way to prevent this algae growth is to provide sunlight and natural ventilation to dry the roof. Obviously, this is not always possible. At least keep all tree branches and leaves about 4 feet away from the roof.

Short of replacing the roof, there is no good quick fix. You could try killing the mildew with laundry bleach. Spray or brush a strong bleach solution on the roof and wait until the areas are lighter. Then rinse well. You could also use a mildew wash that is sold in paint stores for washing painted wood siding.

Several cautions about using bleach: protect yourself, the gutters, and plant materials. Spilled bleach solution can kill grass and bushes. Use eye and skin protection. Do NOT walk on the roof while cleaning. It will be slippery and dangerous. Work from a ladder or use other special equipment. Flush the gutters and metal flashing well to prevent damage. I suggest you hire a professional roofer for the cleaning.

You can also purchase a product called Shingle Shield, which consists of zinc strips that are placed under the shingles near the peak of the roof. The zinc reacts with rainwater to produce a chemical that prevents the growth of fungus and mildew. Again, c onsult a professional roofer. Although the product inhibits the growth of new algae, it may not remove existing algae.

If you ever plan to replace the roof or build a new house, keep in mind that several shingle manufacturers offer shingles with a built-in mildew-resistant chemical.

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Cleaning dirt and stains from a concrete driveway

The quickest and easiest way to clean a concrete driveway is with a high pressure water washer. Rent a heavy duty model with a wide sweeping tip, and blast away. You will be amazed at how quickly dirt and grime are removed. You’ll also want to use the washer on your patio furniture, fence, car, and maybe even the house. However, use caution when cleaning wood or aluminum siding. The strong spray may damage wood and caulk, and it can drive water behind the siding.

You can rent a high-capacity unit from any tool rental store for about $60 per day.

The pressure washer will not remove all mildew, rust, oil, or paint stains on the driveway. You must treat them before or after the big blast.


If dark stains remain on the concrete after pressure washing, test a small are a by dampening the stain with fresh laundry bleach. If the bleach lightens the stain within a few minutes, the stains are mildew and can be removed by bleaching.

If you bleach the surface, use a product called Jomax with a laundry bleach and water solution. Jomax is a mildewcide and detergent that activates the bleach, creating a much more effective cleaning solution. You will need to use eye and skin protection and protect plants in the area. Follow label instructions, and use the cleaning solution within 2 hours after you prepare it. Spray plants in the area with water before and after the application to avoid damage. You can also protect plants by covering them with plastic.

Apply the solution with a garden sprayer or mop it onto the surface. Heavy mildew may require some scrubbing. After 5 minutes, rinse well.

Oil stains

You can use a commercial cleaner, a strong detergent, or dry Portland cement to remove oil stains from concrete.

Commercial cleaners labeled for use as driveway or cement cleaners are available at most hardware or automotive stores. These are usually solvent-based and require you to scrub the solvent into the oil stain. UGL Dryloc Concrete Cleaner and Degreaser works well. Follow the directions on the product you buy. You may wish to use a product that can be washed off with water.

Most strong detergents will remove oil stains. Try liquid dishwashing detergent, slightly diluted with water. Other detergent cleaners that work well include Spic and Span, Soilax, and Mex. A strong detergent such as TSP can also remove most oil stains if applied with a stiff scrub brush. Scrub the spot several times and rinse well with water. Letting the detergent solution soak in for several hours also aids in stain removal.

Finally, you could try pouring a little dry Portland cement or hydraulic cement on the oil stain. Rub it in with a broom, a brush, or even your shoe and let it stand overnight. The cement will draw the oil out of the concrete. Sweep up the residue and repeat if any stain is still visible. If a stain remains, dampen the powder af ter sweeping, and the cement will bond with the surface to freshen the appearance.

Cement’s fine powder can damage eyes and skin. Take safety precautions. The cleaners described above also use strong chemicals, so follow precautions on the label. Let the cleaners do the work, and try several applications if the stain remains.

Rust stains

Try Whink brand Rust and Iron Stain Remove r. You will find it in hardware and grocery stores. This is a powder that comes in a white container with red and blue lettering, not the Whink liquid in the brown bottle. Dampen the stained area with clean water. Dissolve 1 cup of Whink cleaner in a plastic pail with 1 gallon of cold water. Apply cleaner to the surface with a soft brush. Scrub until the stain disappears. Then rinse thoroughly.

You can also bleach rust stains with oxalic acid or a cleaner such as Zud that contains oxalic acid. Wet the stained area and sprinkle with Zud to make a slurry. Cover the area with plastic to keep it moist. Check and scrub it periodically until the stain is gone.

If the rust stain is persistent, try oxalic acid, a more powerful oxidizer and stain bleach. It is available in drugstores and hardware stores and is often sold as wood bleach. Wear protective clothing and eye protection when working with this strong chemical. Use 3 pound of the acid powder per quart of water. Mix the powder in the water and soak the area with the mixture, then let it stand for several hours, scrubbing periodically. For stubborn stains, apply more solution and let it stand longer.


If paint splatters have dried on concrete, a high pressure water washer is your best be t for a first try at removing them. If the paint proves to be too stubborn, you can still use the washer to clean many other things outdoors.

Paint stripper will also remove these stains. I prefer a paint stripper that cleans up with soap and water. Follow the specific instructions for the stripper you purchase, and observe all safety precautions. Remember to allow time for the chemicals to soak in and work. You can use a scrub brush and hose to clean up after using water-washable stripper.

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Sealing concrete

Frigid weather and snow-melting chemicals can easily damage concrete surfaces, allowing moisture to penetrate. The freeze/thaw cycle of moisture in the concrete creates pressure which makes the surface scale and spall (break into chips or fragments).

I recommend using a clear sealer on concrete driveways. This protects the porous surface and keeps stains from penetrating. Sealer also helps prevent salt damage.

Several manufacturers, including DAP, Thoro, Thompsons, and UGL, produce concrete sealers. These are available at most hardware and building supply centers. You can spray, brush, or roll them on after you have thoroughly cleaned your driveway and allowed it to dry.

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Sealing the gap between driveway and garage

Often there’s a gap between a concrete driveway and the garage slab. Filling the gap to keep water out is worth the effort. You can do this with backer rod and filler material.

First, clean the void, blowing away all dust and dirt.

Because of the depth of the opening, you need to support the filler you’ll put into it. Use a caulk backer rod for this. It’s a stiff, closed-cell synthetic material that looks like stiff Styrofoam insulation in a rope form. Buy a size that is slightly wider than the opening so friction can hold it in place.

Force the backer rod into the opening with a putty knife until it’s about 1 inch below the concrete surface.

The backer rod supports the filler as it cures and allows for expansion and contraction. It also provides a surface that does not adhere to the filler. If filler or caulk is attached on three sides, it can’t expand and contract properly, and it will tear away from one side.

Once you’ve installed the backer rod, add special concrete filler or urethane-type caulk. You may need to visit a ceme nt or concrete supplier to find this product. One type is provided in a sausage-like skin that you squeeze, applying the product like decorative cake frosting. The product will fill the void and is self-leveling. These special fillers/sealers will adhere well to the concrete, expanding and contracting with the movement of the concrete.

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Repairing broken concrete surfaces

Small cracks in a concrete driveway or sidewalk are normal and don’t need repair. Driveways and sidewalks have control joints set into the surface to limit the extent of cracking, though the joints don’t always prevent small cracks.

When concrete sidewalks or steps are badly damaged, there is no easy fix. You can try special cement patching compounds, but most won’t stand up to severe weather and will flake off in a short time.

Consider replacing the steps if they are not too large or expensive. Often when concrete steps are damaged or broken, the adjacent sidewalk also needs repair. This makes replacement a good option.

If the steps and walks are in basically good condition, you could patch the concrete with epoxy patching material. Abitron is a leader in epoxy patching for wood and cement. The company offers special products for various applications and provides good instructions.

In general, epoxy will bond well to damaged surfaces and can be cast into a mold to copy an existing shape. First you’ll need to clean the surface and remove all loose material. Sandblasting or acid etching may be necessary to prepare the concrete surface.

Uneven surface / heaving

If a driveway or sidewalk is heaving and displaced at the cracks, this indicates a problem with moisture and/or the fill underneath the concrete. Try grading the soil to channel surface moisture away from the concrete. The only proper fix for serious heaving is to replace the drive and ensure proper fill and grading upon replacement.

A crack near your home that allows lots of water to leak under the slab or into the basement should be filled with special flexible filler. Visit a concrete supplier and ask for professional-grade filler made of epoxy or polyurethane like that used on sidewalks at shopping malls. This filler comes in a caulk tube that’s like an applicator for cake frosting. It’s important to use such a filler because it remai ns flexible as the concrete slabs move due to changes in temperature and moisture. A solid, cement-based filler would re-crack.

In any crack deeper than 1 inch, the filler will need support from a backer rod–a flexible foam rope that you stuff into the crack. The backer rod is wider than the crack so it will stay in place once it’s stuffed in. Above the backer rod, leave space for the filler. This space should be rectangular, and about twice as wide as it is deep.

To make the repair, first clean the crack with water or high-pressure air. Allow to dry. Force the backer rod into the crack, then flow filler material on top of it. The filler will bond well with the concrete. Filler material should only touch two sides of the crack (the backer rod supports the lower edge) so the material can stay flexible, moving without tearing as the slabs expand and contract.

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Mudjacking to level exterior concrete

If your landscaping or driveway has a large area of concrete that has settled unevenly, such as a large patio that now pitches toward the house and threatens the basement with leaking rainwater, the area may be a candidate for mudjacking.

Mudjacking–concrete leveling or concrete raising–is a process utilizing hydraulic pressure to raise and level concrete s labs. A hole about 2 inches in diameter is drilled through the slab. A machine pumps a mixture of water, ground stone and perhaps some Portland cement into the hole. This stiff "mud" mixture lifts the slab.

A proper mudjacking job involves drilling several holes and filling most of the void under the slab. The mud will harden slightly because of the cement, but most of the support is provided by the ground stone.

If the slab is in good condition with few cracks and a sturdy surface, mudjacking is an excellent alternative to replacing the slab. Done properly, the repair will last for several years. The cost is usually a fraction of concrete replacement.

Check contractors’ references. Find someone who has several years of experience. Check on warranties. A good contractor will provide at least a 1- year warranty. The mudjacking process is somewhat of an art since you can’t see where that mud is going under the slab. Problems can reoccur within the first year, and a warranty ensuring free repairs is important.

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