What it is: Lumber from sustainable sources; natural beauty and durability without the guilt. Choices in environmentally friendly flooring range from certified lumber harvested under Forest Stewardship Council (FSC) guidelines to recycled and engineered wood.
What makes it green: FSC certification, which tracks lumber to sustainably harvested sources.
Recycling: Repurposed wood comes from such sources as old barns, wine tanks, or trestles.
Technology: Engineered flooring maximizes supplies by bonding veneers on a plywood base.
Cost: $10 to $19 per square foot.
What it is: Bamboo and coconut palm, like wood, make warm-toned floors. Timber bamboo (a grass) produces a hard surface that ranges from light yellow to amber. Coconut palm is handsome and richly grained; it's slightly softer and varies in color.
What makes it green: They're fast growing and underutilized, reducing the demand for lumber. The densest, best-wearing bamboo product is made of bamboo strands molded together on overlapping layers. Be sure that glues are low-VOC (volatile organic compound) and that bamboo grew to maturity.
Cost: $6 to $8 per square foot.
What it is: Bark from cork oak trees makes warm, resilient, sound-absorbing flooring. Appropriate for most rooms, including bathrooms (where installed tiles are coated with polyurethane or silicone). Many patterns, natural browns, and applied colors. Compatible sealants are recommended.
What makes it green: Cork oak bark is sustainably harvested every 10 years, and the trees, native to the Mediterranean region, often live 100 years. The cork sheets used for flooring often are made from the salvaged by-products of wine cork manufacturing.
Cost: $6 to $8 per square foot (12- x 12-inch tiles) or $7 to $9 per square foot (1- x 3-foot snap-together planks).
What it is: Made of ceramic, glass, or stone, tile has unrivaled durability. It works in high-traffic areas such as entries, kitchens, and hallways. Manufacturers now offer more floor tiles with the look and color range of stone, ceramic tile, terra-cotta, or terrazzo, but with recycled content.
What makes it green: Recycled-content tile makes use of otherwise wasted by-products diverting glass, used tiles, granite dust, stone tailings, and unfired material from landfills and offsetting its high "embodied energy" cost (price of energy required to get a product from its source).
Cost: $4 to $24 per square foot.
What it is: Linseed oil, pigments, and pine rosin. Invented more than 150 years ago, linoleum remains one of the greenest products sold. It comes in many colors and patterns, doesn't require waxing, and can be cleaned with soap and water. Some have snap-together panels.
What makes it green: It's made of natural, renewable resources, no toxic or VOC-outgassing products are used in its production, and it inhibits bacterial growth. (Chemically sensitive people should be aware that it carries the distinct smell of linseed oil.) Click-together flooring doesn't require gluing.
Cost: $4 to $6 per square foot (tiles) or $30 to $40 per square yard (sheets).