These days, it's a no-brainer to choose green building materials.

With so many top-quality options available, you can make a new home energy-efficient and healthy from the ground up, cutting back on the amount of resources consumed for decades to come and all but eliminating health-zapping chemicals.

Eco-friendly insulation, flooring, roofing, countertops and finishes all come in a wide variety of materials for all tastes and budgets.

What exactly makes a building material green? Global Green USA says that any so-called sustainable building product should fit into at least one of these five basic green building categories: saving energy, conserving water, contributing to a healthy indoor environment, protecting natural resources or reducing a building's impact on the community.

Here are a few green building materials you can consider for your next project:

Insulation

There's a reason why blue jeans are such a classic fashion staple — they're soft, comfortable, cozy and warm. So why not dress a house in denim, too? Companies like UltraTouch offer rolls of denim insulation made with high quality natural fibers that aren't just mold-resistant, free of harmful volatile organic compounds (VOCs) and easy to work with — they're made from 90 percent post-consumer material i.e., last season's castoff jeans.

Not that fungus in the walls is always a bad thing. The latest and greatest natural insulation material is made from mycelium, little white root-like mushroom fibers that form underground. This super-green building material is nontoxic, fireproof, mold-resistant and stronger than concrete. Most importantly, it traps more heat than fiberglass insulation.

Flooring

You want flooring to be both durable and beautiful, and both requirements can easily be met with green building materials like bamboo, cork, sisal, recycled carpet and reclaimed wood. Look for nontoxic natural stains in hard-wearing, renewable FSC-certified bamboo flooring like that sold by EcoTimber. Resilient cork flooring is sustainably manufactured by periodically peeling off the outer layer of bark from farmed cork oaks, while strong and versatile sisal carpets resist deterioration and provide great natural sound insulation.

Recycled and reclaimed materials might be even greener. FLOR's modular carpet tiles are made from 85 percent recycled fibers, and reclaimed wood floors can give a home a warm and welcoming look.

Roofing

Metal roofing makes rainwater collection easy, and though its manufacturing is energy-intensive, the trade-off is its longevity. Light colors are even better, reflecting sunlight and reducing warm-weather cooling costs.

Stump-sawn cedar shingles like those from True North Cedar are naturally insect- and rot-resistant, and you can get a similar look with even greater benefits from recycled rubber tiles.

Of course, no eco-friendly roofing discussion is complete without a mention of living green roofs, which feature grasses or ground cover planted on top of waterproof membranes.

Countertops

It's hard to get much prettier than the sparkling bits of recycled glass in IceStone or Vetrazzo countertops, but surprisingly, recycled paper is a contender.

PaperStone is made from 100 percent post-consumer recycled cardboard embedded in durable resin. Reclaimed wood from wine barrels or barns brings lots of character into the kitchen, and recycled aluminum countertops add a bit of shine.

Finishes

Like icing on a cake, finishes such as paint, stain and varnish top off the beauty of a home but they can also be the source of indoor air contamination. Look for products with low or no VOCs to preserve air quality. Benjamin Moore's Natura line of paints received high marks in a recent evaluation by Consumer Reports. Milk paint is a natural and old-fashioned alternative, and water-resistant beeswax or hemp finishes keep wood looking its best.

Do you have experience with other green building materials? Tell us about them in the comments below.

See also:

Eco-friendly building products

Sustainable building materials

Sustainable building: Four examples