Glass in energy-efficient windows can prevent 80% of sunlight from entering a home.

But units with vinyl frames are made with a toxic material. Choose frames made with aluminum, wood, or fiberglass as better options.

While these tubes do save energy compared to skylights, both tubes and skylights eliminate roof insulation, which increases heating and cooling costs.

If a fireplace is indoors, it should be sealed and have adequate combustion and ventilation air. However, no type of indoor combustion of ANY fuel (including ethanol replacement for wood and even candles) is completely safe, as they will release toxic particulates and gases.

Residential LEDs (light emitting diodes) have increased in quality and decreased in cost since the first ones were marketed in about 2009. Look for products that have good color quality (a Color Rendering Index of 90 or above). And if you use LEDs in enclosed fixtures (with little exposure to air) or in dimmers, make sure the product is rated for these uses. Otherwise, they may not last very long.

In the vast majority of cases, ceiling insulation and weatherization are more effective than solar attic fans.

Hazardous chemicals in paint include Volatile Organic Compounds, biocides, antifreeze, and alkylphenol ethoxylates (surfactants that are acutely toxic endocrine disruptors that bioaccunulate in the food chain).

Some ingredients in caulking can be extremely toxic. They include solvents, phthalate plasticizers, and isocyantes.

Though every product is different and Safety Data Sheets should be reviewed, plant- and acrylic-based caulks are the safest classes of products. Polyurethane is the most toxic class of caulk.

Carpet and vinyl can contain toxic petrochemicals, Teflon stain resisters, coal ash filler, flame retardants, and antimicrobials. Together they make up more than 2/3 of flooring sold in the U.S. Carpet is also difficult to clean, and sometimes uses toxic solvents to do so.

The best flooring for the environment and indoor air quality is usually smooth (non-fibrous), and made from non-toxic plant or ceramic materials such as wood, natural linoleum, cork, tile, or stone.

Actually, the safest floor mount is the one without chemicals. Nails, carpet tacks, and "Floating floors" that use shoe moulding to hold the floor in place are environmentally preferable to chemical adhesives. Peel-and-stick strips are also a good choice since most of their toxic offgassing takes place when they are manufactured.

If using chemicals, plant- and acrylic-based adhesives are the safest class. Polyurethane and epoxy are the more dangerous classes.

Composite, non-structural, wood is used in the manufacture of cabinets, countertops, doors, floor underlayment, flooring, furniture, moldings, and shelving. These products can emit formaldehyde.

Products with fewer emissions are either made of solid wood (as opposed to fiberboard or particle board) or are manufactured with no added formaldehyde and employ soybean oil-based resins.

• If you choose stone, granite and quartzite are extremely hard and durable. But avoid using toxic Teflon-based sealants.

• If you choose tile, avoid products that might have lead-based pigments the glazing.

• If you choose laminate, it is best to buy it premanufactured, because onsite installation can increase VOC emissions found in the adhesives.

• Avoid counter materials treated with antimicrobial chemicals, which generally more harmful than beneficial to health and the environment.

• And poor quality products (that are not easily repairable) of any kind need replacement or refurbishment; such construction creates a different kind of indoor air quality problem.

Gypsum wallboard can often contain "recycled gypsum" from coal ash, with toxic minerals and heavy metals such as arsenic, cadmium, lead, and mercury. These toxins can be exposed to workers installing the product, and can get into house dust until installation clean-up occurs. When building or remodeling, use as little recycled gypsum as possible.

Insulation can affect the indoor or outdoor environment even if it is wall-off in the building's shell. Though formaldehyde has been removed from many fiberglass and rockwool products, some fiberglass ductboard and rockwool batt products still may contain this chemical, which can offgas Volatile Organic Compounds (VOCs) into a home. Make sure to consult the Safety Data Sheets. Spray foam insulation that is not properly installed can also offgas VOCs into a home, including formaldehyde and asthmagens.

Foam board insulation can contain toxic fire retardants and pesticides that can leach into the outdoor environment.