Six three- and four-way switches will be installed here once the house is complete. The wiring looks complex, but it is not.

Q: Tim, I need you to mediate a dispute between my husband and me. We’re building a new home, and there are quite a few places where two or more switches can be used to control lights. I like the convenience but my husband has had nothing but problems trying to troubleshoot these three- and four-way switches. He wants nothing to do with these “wretched switches,” as he refers to them. Your vote will decide the issue. (I have to add that pecan pie and moist pumpkin bread are two of the favorite things I like to bake.) — Veronica B., Lakeland, Fla.

A: There is no need to bribe me with desserts, as I am a huge fan of three- and four-way switches. I wish I could meet the engineer who many years ago figured out how to make these magnificent switches that allow you to control a light, or group of lights, from multiple locations.

The most common uses for these switches are at the top and bottom of staircases or at the ends of a long hallway. When you use one in a finished home, you might think it is magic that is making it all work. In reality, you just need special switches that are readily available. You also need to have a special cable with one extra wire that runs between the two switches.

The simplest setup is to have just two three-way switches control one light. A three-way switch has three screws on it, plus the green grounding screw. A standard single-pole switch only has two screws on it, plus the green grounding screw.

That extra screw on a three-way switch confounds almost all homeowners and apprentice electricians, judging from the emails I get every week asking for help. There are a few ways to connect two three-way switches together, but I prefer the method where you use a cable that has an extra red wire in it. It is called three wire with a ground.

The real fun and magic of these switches is when you have a situation where you want to control some lights or an appliance from three or more points. My daughter is building a new home right now, and she’s got at least five sets of lights in her home that are controlled by four switches.

To achieve this higher level of electrical wizardry, you install four-way switches in between the two three-way switches in the circuit. A four-way switch has four screws on it, plus the green grounding screw.

To make the wiring work flawlessly, so your husband becomes a lover of these switches, you install the same special three-wire cable in between all the three- and four-way switches in the circuit. That lovely red wire along with the black wire in the cable will do all the heavy lifting, and your husband will think all the switches in your new home were sprinkled with pixie dust.

I have three helpful videos at AsktheBuilder.com showing you how fast and easy it is to wire up and troubleshoot three- and four-way switches. Collectively these videos have been watched by over 2 million people, saving them hundreds of thousands of dollars on electrician and divorce attorney fees!

Q: What is the best deck cleaner for both wood and composite decks? There’s lots of conflicting information out there on the Internet. Many people say to mix chlorine bleach with water in a 50/50 solution. Others say to blast away using a pressure washer. — Lori S., Portland, Ore.

A: I have tried all the methods mentioned and discovered, quite by accident, the best way to clean a wood deck.

I have always known chlorine bleach is the worst thing to use outdoors to clean decks, patios and sidewalks. A neighbor in Cincinnati using chlorine bleach killed a magnificent maple tree that provided luxurious shade on her rear patio. Each spring she would dump three gallons of pure bleach on the patio and scrub away to rid it of algae. I told her it was a mistake, and she ignored me. The tree got sicker and sicker and eventually had to be cut down.

Other friends of mine and many contractors feel pressure washers are the answer. Yes, they are magnificent tools and blast away mildew, dirt and sun-damaged sealers. But the high-pressure stream also erodes the soft, light-colored spring wood between the darker bands of summer wood in the decking. Soon, your deck looks and feels like a 50-year-old fishing pier.

Twenty-five years ago I was doing research for how to seal a wood deck. I interviewed a manufacturer and casually asked about using chlorine bleach as a cleaner. He responded: “Oh, that’s the worst thing to use. You want to use oxygen bleach. Call this chemist and he’ll tell you all about it."

I made the call, and it changed my entire opinion about how to clean anything that is water washable, including wood and composite decking.

Oxygen bleach is readily available. There are quite a few brands. I would recommend one that is certified organic. Oxygen bleach is not toxic to vegetation. It does not bleach the color of wood as chlorine does. There is no foul odor when you use oxygen bleach.

Oxygen bleach comes as a powder you mix with water. Use warm or hot water and stir until all the powder dissolves. Work in the shade and apply the solution to dry decking so it soaks into the wood to deep clean it. Apply the solution liberally and allow the oxygen bubbles to work for at least 15 minutes before lightly scrubbing the decking with a medium scrub brush. Rinse well with clear water, let dry and you will be amazed at how clean your wood is!

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