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I’ve been wondering about how to eliminate mold — for good. How can I get rid of mold growth in my home?

Mold growth is an ever-present possibility in homes, and Eliminate Moldthough not all molds are dangerous, identifying which ones are harmful can be difficult. You should thus eliminate mold when you find it by addressing the root causes and then killing the dormant spores left behind.

Mold grows only when sufficient moisture encounters organic materials, so moisture control should always be the first step toward managing mold growth. Increase your home’s ventilation enough during winter to eradicate or greatly reduce window condensation that could trigger mold growth. Proper ventilation will also help curtail the moisture buildup in other places, too. A heat recovery ventilator (HRV) is the best way to boost ventilation and will also improve indoor air quality.

A bleach-and-water solution is a traditional means of killing mold, but this method isn’t always effective. The best way I’ve found to get rid of mold is to use a fungicide called Concrobium Mold Control, which is registered by the Environmental Protection Agency. This product contains sodium bicarbonate (baking soda), sodium carbonate (washing soda) and trisodium phosphate (TSP). It’s a transparent, odorless, non-sticky liquid that kills mold and mold spores as it dries. It also offers some residual mold control. Brush or spray it onto moldy surfaces. Professional mold-abatement workers employ fogging units to deliver this same product over large areas inside of buildings infested with mold. A companion product called Mold Stain Eraser uses oxygen-based bleaching to eliminate mold stains with little or no scrubbing

Photo courtesy Concrobium Mold Solutions: Concrobium Mold Control is registered by the Environmental Protection Agency, and is a fungicide that effectively eliminates household mold.

Contributing Editor Steve Maxwell has been helping people renovate, build and maintain their homes for more than two decades. “Canada’s Handiest Man” is an award-winning home improvement authority and woodworking expert. Contact him by visiting his website and the blog, Maxwell’s House. You also can follow him on Twitter, like him on Facebook and find him on . 


What is BPA and why is it bad for me? How can I avoid BPA and other chemicals in plastic?

You’ve heard correctly! Bisphenol A (BPA) is a synthetic chemical that has been widely used in plastic manufacturing since the 1950s. The compoundChemicals in Plastic is used to line metal cans of food, and to form many plastic containers and cash register receipts. As convenient as plastic packaging is, and as pervasive as it has become, you should still try to choose different packaging or otherwise limit your exposure to BPA because of the health risks.

As is so often the case with many modern chemicals, many plastics are deemed safe because they seem to have no ill effects after short-term exposure. Unfortunately, scientists have recently shown that plastics can off-gas or leach toxic compounds into the surrounding environment in relatively small but sometimes physiologically significant quantities. Bisphenols appear to be one (among many) of those compounds leached from plastic.

The most serious concern about BPA is that it disrupts the endocrine system. Endocrine disruptors are insidious, interfering with normal, often very fine-tuned and subtle interactions among our bodies’ natural hormones, hormone receptors, and the physiological processes they regulate. If fetuses, infants or children are exposed to persistent doses of an endocrine disruptor, they may experience developmental ramifications, such as abnormal growth patterns. In 2012, the Food and Drug Administration halted BPA use in baby bottles, sippy cups and plastic formula packaging. The FDA claimed to have made the decision based on market demand, not safety. Manufacturers insist only high levels of BPA will cause endocrine disruption. Independent scientists say any amount is too much. As a biochemist who has studied this issue, I say you should avoid all exposure to endocrine disruptors.

Are you safe if you choose packaging or products that are labeled “BPA-free”? Perhaps not. Many BPA-free products are indeed free of BPA. However, Bisphenol S is a common substitute, and that compound may be just as toxic. And bisphenols may only be the tip of the iceberg when it comes to unsafe chemicals in plastic. Phthalates — synthetic compounds that help make plastic flexible — are even more pervasive in plastics than bisphenols and have been linked to asthma, breast cancer, diabetes, obesity and more. Phthalates, or their chemical components, are commonly found in human urine. The Centers for Disease Control reports that phthalates are present in the bodies of most North Americans.

Because of the prevalence of plastic, taking complete control of your BPA consumption will be difficult, but reducing your exposure is entirely achievable. Eat fresh, local foods when you can — many grocery stores sell produce without plastic packaging around it, and you can then transport your fresh food in a reusable cloth bag. Buy food packaged in glass containers as often as possible, and use glass, porcelain or steel containers to store and reheat food. You can also drink from a BPA-free stainless steel bottle. These tactics will help lower the levels of bisphenols and phthalates in your body, in spite of their pervasiveness in our plastic-packed world.

Photo courtesy Rubbermaid: Many manufacturers now offer plastic products free of Bisphenol A (BPA).


I want to buy a portable table saw for constructing outbuildings around my property, and for making furniture in my shop. What should I look for?

For a portable table saw that will suit your needs, Portable Table Sawyou have two main choices: a benchtop model or a contractor model. Benchtop saws have aluminum tops and are the lightest and most easily movable. The best models include folding support stands with wheels for easy portability and vacuum connection ports for effective dust control. The name “benchtop” is a little misleading, though, because these saws are typically operated on stands. Quality benchtop models cost about $500. Some cheaper table saws that look similar are available, but their capacity and power will disappoint any serious user.

Contractor table saws are heavier and don’t have folding stands, but they do offer a more stable, cast-iron working platform that’s typically larger than what you’ll find on a benchtop saw. Contractor table saw prices start at about $800.

So the core question is how important portability is for you. If you won’t be moving your saw often, a contractor model may serve you better. It’ll be larger and thus more stable, though few contractor saws can connect to a vacuum for sawdust control. If you really need the benefit of easy portability, then a benchtop saw is the way to go. There’s no significant power difference between benchtop and contractor models.

If you decide to go with a benchtop saw, consider building a stationary out-feed table in your shop. Build it so the saw will fit right into a cutout in the surface, and you’ll enjoy a large support area for cutting plywood and other materials safely, all without sacrificing your saw’s portability.

Photo courtesy Robert Bosch Tool Corporation: A folding stand and wheels make for an easy-to-move benchtop saw.

Contributing Editor Steve Maxwell has been helping people renovate, build and maintain their homes for more than two decades. “Canada’s Handiest Man” is an award-winning home improvement authority and woodworking expert. Contact him by visiting his website and the blog, Maxwell’s House. You also can follow him on Twitter, like him on Facebook and find him on . 


What’s the difference between a “passive solar” home and a home built to “Passive House” standards? Is one better than the other?

“Passive solar” is a design approach that was popularized inPassive House Standards the 1970s and in which heat from the sun is strategically captured to warm homes. Passive solar’s low-tech approach doesn’t abide by any established standard, but the design principles are consistent: Passive solar homes capitalize on solar heat that radiates through south-facing windows (north-facing windows if the home is in the Southern Hemisphere). As the sun warms the house, the heat is retained via insulation and by use of thermal mass — such as concrete, stones or tile — that stores and slowly releases it.

About 20 years after the popularization of passive solar homes, German physicist Wolfgang Feist founded the Passivhaus Institut (PHI), which formalized “Passivhaus,” a comprehensive energy-efficient building standard that was influenced by early passive solar designs, but which placed more importance on an airtight envelope, high-efficiency windows and conditioned air recovery. By 2010, the newly formed Passive House Institute U.S. (PHIUS) had carved out a place for the extremely efficient, very specific and highly demanding standard in the U.S. market. PHI and PHIUS are now working separately to advance Passive House standards in the United States.

The goal of the standard is to achieve a durable, comfortable home with overall energy savings of 60 to 70 percent compared with conventional new homes, including a 90 percent reduction in space-heating requirements. A home must follow the standard exactly to receive Passive House certification. With the dramatically reduced energy requirements, the need for conventional heating and cooling systems disappears. This frees up financial resources that can instead be used to make a home deeply efficient. Adding renewable energy systems becomes more affordable, because a smaller energy-generation system can now meet the much smaller energy demands of a certified Passive House.

The rigorous Passive House standard doesn’t render passive solar design entirely obsolete, however. Many homes built to the Passive House standard rely on passive solar design as one tactic among many to make the home super-efficient. But Passive House certification goes beyond passive solar details and ultimately offers superior performance. Thanks to modern building techniques and products, Passive House buildings allow for far more design innovation than passive solar homes, particularly for structures without ideal sun exposure. Regardless, buildings should incorporate passive solar techniques before active solar techniques, such as solar panels, enter the picture.

For more information, visit the websites for the Passivhaus Institut and the Passive House Institute US.

Photo by Rick Pharaoh Photography: Passive House-certified homes combine captured sunshine and high-tech design for increased comfort and deep efficiency.


I have heavy clay soil that becomes as hard as a brick when it dries, and my neighbors who also garden have asked me how to improve clay soil. What are the best methods for improving clay soil?

First, the good news: “Of the three major soil components — sand, silt and clay — clay has the highest nutrient content,” says Garn Wallace, president of Wallace Labs, a Improve Clay Soilsoil-testing firm in El Segundo, Calif. Clay soils retain minerals in forms that are readily available to plants and that aren’t water soluble, so rain and irrigation water are less likely to leach them away. The trouble is that clay lacks good porosity. Its fine-textured particles tend to clump tightly together. Air, water, roots and seedlings can have trouble moving through it, so crop yields may be lower. (Plus, clay is a pain to work in!)

Increasing your soil’s organic matter is the first and most important step toward improving heavy clay soil. Organic matter invites in more porosity-improving earthworms. Work in compost, grass clippings, shredded leaves or other organic materials. Plant and turn under cover crops, and safeguard your soil’s surface with an organic mulch to prevent crusting. Sand or peat moss can also improve soil texture, but they lack many of the other benefits of organic matter, such as beneficial microbial activity and nutrients for your plants to uptake. Plus, you’ll need a lot of sand to make a real difference (1 part sand to every 2 parts clay soil).

Photo by Dreamstime/Ian Nixon: Don’t be foiled by your heavy clay soil: Add organic matter to soften up your tough terrain.

Vicki Mattern is a contributing editor for MOTHER EARTH NEWS magazine, book editor and freelance magazine writer. She has edited or co-authored seven books on gardening, and lives and works from her home in northwestern Montana. You can find Vicki on .


I’ve heard there’s a link between catching colds and flying. Am I more likely to get sick if I travel on a plane?

Yes! According to a 2004 study Catching Colds and Flying on Planespublished in the Journal of Environmental Health Research, plane travelers are up to 113 times more likely to catch a virus than their ground-bound counterparts.

Why is this? The study put forth a series of potential culprits: fatigue, low outside air replacement, dry cabin air, and proximity of people to one another in a small space. While all of these may play a part, the researchers found that an airplane cabin’s low humidity — which weakens humans’ defenses against infection — is likely the greatest factor in passengers’ heightened susceptibility to infection.

Use these preventive tactics to keep from catching a cold the next time you catch a flight: Get plenty of sleep before your trip, stay well-hydrated, wash your hands often, and avoid touching your face or mouth. Boost your immunity pre-flight by supplementing your diet with medicinal herbs, such as astragalus, garlic, ginger and ginseng, and medicinal mushrooms, such as maitake, reishi and shiitake.

For even more helpful information on staving off infection, check out our comprehensive article 19 Ways to Prevent and Treat Colds and Flu.

Photo by Fotolia/Subbotina Anna: Preventive tactics such as getting plenty of sleep and staying hydrated can help prevent sickness when flying.


Can you recommend some tomato varieties that will continue to produce fruit when temperatures are high?

Faced with long bouts of daytime temperatures higheHeat-Tolerant Tomato Varietiesr than 85 degrees Fahrenheit and nights above 72 degrees, tomatoes may fail to set fruit. The plants may look dark green and vigorous — evidence that all other growing conditions are favorable — but have blossoms that dry up and fall off.

If the heat spell lasts no more than a week, the tomato plants will quickly recover. During long stretches of warm nighttime temperatures, however, the plants will stop setting, causing a subsequent gap in tomato production.

In recent years, a flood of new varieties has been bred for greater heat tolerance. Known as “heat-set” tomatoes, or “hot-set” tomatoes, some commonly grown hybrids are ‘BHN 216,’ ‘Florasette,’ ‘Florida 91,’ ‘Heatwave II,’ ‘Solar Fire,’ ‘Summer Set,’ ‘Sunchaser,’ ‘Sun Leaper,’ ‘Sunmaster,’ ‘Sun Pride’ and ‘Talladega.’ According to the Alabama Cooperative Extension System, many heat-set varieties also perform well in cool, rainy weather.

Some heirloom tomato varieties are heat-tolerant as well, and these include ‘Arkansas Traveler,’ ‘Eva Purple Ball,’ ‘Hazelfield Farm,’ ‘Homestead 24,’ ‘Illinois Beauty,’ ‘Neptune,’ ‘Ozark Pink’ and ‘Tropic.’ Additionally, some “cold-set” varieties, such as ‘Stupice,’ are all-weather standouts because they’re able to function in hot weather, too. A handful of cherry tomato varieties, such as ‘Lollipop’ and ‘Yellow Pear,’ also do well in prolonged stints of heat.

Tomato growers in the South often choose heat-tolerant tomato varieties for summer and fall production — a strategy growers farther north may want to emulate now that climate change is causing hotter summers in most regions. When growing tomatoes in hot temperatures, you can boost your success rate by planting deeper (where the soil temperatures are lower), providing afternoon shade, watering in the morning and using thick organic mulch to keep soil cool.

Learn more about heat-tolerant tomato varieties in the Alabama extension publication Blossom Drop in Tomatoes and the Louisiana extension publication Performance of Hot-Set Tomato Varieties in Louisiana. To find sources for some of the heat-set tomato varieties mentioned here, use our Seed and Plant Finder.

Photo by Tomato Growers Supply Company: 'Stupice' tomatoes thrive in cold weather and can also handle heat.

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