Episode Two: Foundation

"We're building a beautiful straw-bale home here in Santa Barbara, California, that the three little pigs would envy. Today we're going to talk about straw-bale building before preparing and pouring the foundation. We're going to visit with experts to find the best choices for our floors and discover other healthy, cost-effective building materials. Whether you're looking to build from the ground up or simply looking to green up, it's all right here."

— Building Green Host, Kevin Contreras

First, an Introduction to Straw Bale Building

Straw can be made out of rice, wheat, barley or flax. Kevin decides to go with rice straw because of its high silica content, which makes it extremely resistant to both fire and rot. It’s also highly insulating: A bale by itself has an R rating of 45, more than twice as insulating as the minimum R- value for California building codes. Even Building code officials and insurance companies are beginning to look favorably on straw bale construction for its tremendous energy efficiency and fire resistance. And it’s affordable–Kevin is able to purchase enough straw to build a 4,000 square foot house for less than $3,000.

For a glimpse of straw bale history, take a tour with Kevin of the Burritt Museum, housed in a straw bale mansion in Huntsville, Alabama, that has been standing tall since 1938.

The Pros and Cons of Steel Frame Construction

Santa Barbara is earthquake country, which means Kevin needs to build a post and beam structure to support the bales. The pre-cut steel beams are made of 66% recycled material, are straight, termite-free, and have half the weight and twice the strength as wood. On the down side, steel isn’t always the greenest choice in terms of embodied energy.

Even Concrete can be Green

Concrete actually has a lot to recommend it, according to green architect Eric Corey Freed, “It’s an all-natural material: cement, sand, water, stone. It’s made with local materials; it can be built on site; it’s incredibly durable; lasts a long time.” On the down side, concrete uses cement, and the production of cement creates an immense amount of carbon dioxide, a greenhouse gas. The solution to greener concrete is to replace as much cement as possible with fly ash, itself a waste product. As an added bonus, high fly ash content produces a better, more finishable concrete.

Kevin then visits Tom Nelson of Team Transit Mix, his concrete supplier, to find out even more about fly ash used to be a waste product, captured from coal-burning plants and dumped in the desert. It has gone from a waste product to a product that makes concrete more efficient.

Kevin then visits Team Transit Mix’s state-of-the-art concrete recycling center (one of about a dozen across the country) where they recycle leftover concrete to create retaining wall blocks.

Flooring and Health

Before pouring the concrete footings and foundation slab, it’s important to decide what type of flooring will be used on the first floor of the house. Building Green’s health expert, Alyssa Alvord, points out to Kevin that floors “influence indoor air quality dramatically.” Concrete, bamboo, natural wood and cork are all good natural flooring alternatives.

Conventional carpet, which traps allergens and can off gas, is perhaps the worst culprit. The good news is that it can be recycled, and green alternatives are springing up everywhere–just look for the Carpet and Rug Institute’s Green Label. Kevin visits with Ray Anderson, CEO of Interface Flooring, who has been called the greenest CEO in the country, and claims that since going green, his company’s profits are up, costs are down, and the quality of the product has improved.

Easy Green Step

Kevin visits Dennis Allen, who is remodeling an old house to make it greener, to get his advice on how we can make the best floor choices, and talk to him about what people can do right now. Dennis explains that, if you pull up and remove your carpet or vinyl flooring, you can turn your concrete slab into a beautiful finished floor. You can put natural organic stains with organic dyes in the concrete to give it a whole new life.

Then, you can recycle your carpet. Recently, Kevin discovered CARE, the Carpet America Recovery Effort. CARE estimates that 5 billion pounds of carpet were sent to U.S. landfills in 2003. The good news is that carpet recycling facilities are cropping up around the country.

Recycled carpet can be made into composite lumber, both decking and sheets, tile backer board, roofing shingles, railroad ties, automotive parts, carpet cushions, and even stepping stones.

Green Flooring Options

Kevin visits Ellen Strickland at Living Green to discuss green flooring alternatives. Ellen recommends a number of possibilities including: natural linoleum, floor tiles in linoleum, natural wood floors sourced from reclaimed or FSC-certified wood, bamboo, palm wood, precast concrete pavers, concrete slab tiles, natural carpet, and area rugs.

Xtreme Green: Earthen Floors

Still looking for the perfect green flooring solution, Kevin takes a break from foundation work to go on an xtreme green field trip. He visits Santa Barbara City College green building student, Leif Forest Skogberg and learns how to make a beautiful, durable earthen floor with the finish of a burnished clay pot, using a mixture of clay mud, straw and manure and finished to a warm, rich patina with a coating of beeswax and linseed oil. The result is a non-toxic floor and an extremely efficient use of resources.

Radiant Floor Heating

Kevin ultimately decides to go with concrete flooring on the ground floor of his house, applying a finish directly to the concrete slab. But to make sure it’s a cozy concrete floor, the first step is to install a radiant heating system in which solar heated water flows through pipes embedded in the flooring to provide energy efficient heat without the allergens associated with forced air systems.

Next week on Building Green: framing and roofing.