How to Build and Retrofit a Sustainable Home

Building and Retrofitting a Sustainable Home

Whether you’re building from scratch or adding onto an existing home, there are a variety of green building materials and products on the market today to create your sustainable home vision. This guide, useful for homeowners, designers, contractors and builders alike, highlights important green building materials to consider and suggests credible, certified sustainable brands to help you build a truly sustainable home.

Eco-Friendly, Ethically-Sourced Building Materials

RECLAIMED LUMBER

Not only does reclaimed lumber give that rustic, farmhouse look and possess some unique history within its grain, but it also helps preserve our carbon-sequestering forests and rejects monoculture tree farms that do not support biodiversity or ecological health. Choosing reclaimed wood reduces the fossil fuel use and pollution that comes from clearing and processing trees into lumber.

There are several resources for finding reclaimed wood locally and online:

• For free or cheap lumber, try Craigslist, Facebook Marketplace, FreeCycle or 1001Pallets.
• Your local reclaimed lumber dealer or architectural salvage retailer is your best option as it supports the local economy, requires fewer miles to transport the lumber to your building site and it allows you to have a look at the lumber in person and know exactly the quality you’re getting. OldHouseOnline.com has a great directory for finding a salvage retailer in your state.
• A local demolition site, construction dumpster or farm – Be sure to contact the property owner to get permission before hauling away any materials.
• Home Depot, Lowes or other home improvement retailer – Keep in mind that the selection of reclaimed lumber will vary across stores and locations.
• Online distributors such as:
  • Longleaf Lumber, operating out of Berwick, ME and Cambridge, MA, manufactures reclaimed wood flooring, paneling, countertops, mantels, beams and lumber, all of which support LEED certification.
  • Vintage Timberworks of Temecula, CA, has over 27 years of experience manufacturing quality reclaimed wood products. These include solid timbers, custom box beams, fireplace mantels, vintage planks and boards, rustic flooring, exterior siding and decking, timber trusses and more. Vintage Timberworks sources wood primarily from the U.S. and Canada with some coming from Australia, New Zealand and Indonesia.
  • Plank and Mill offers reclaimed wood samples as well as tutorials useful to the novice DIY-er and veteran woodworker.
  • eBay or Etsy – Do your research to confirm that the seller is credible and is indeed selling reclaimed wood. Lumber can easily be finished to look worn and weathered.

Wherever you source your reclaimed lumber from, make sure you understand how the wood has been treated to guarantee that it will withstand the test of time and the elements, while also being free of harmful toxins.

RECYCLED STEEL

Recycling metal rather than using virgin ore helps preserve natural resources and saves energy. In fact, creating products from recycled steel utilizes 40% less water and reduces mining wastes by 97%.

• Cascade Steel Rolling Mills, acquired by Schnitzer Steel Industries Inc., a global leader in metals recycling, is a steel manufacturing facility that turns recycled metal into high quality finished steel products such as rebar, coiled rebar, merchant bar and wire rod. Cascade Steel’s electric arc furnace (EAF) is more energy efficient and environmentally-friendly than traditional blast furnaces. Serving customers primarily in the 10 western states and Canada, Cascade Steel is the only Western U.S. mill capable of obtaining all of its recycled metal from its affiliated recycling operations, minimizing transport emissions. Cascade Steel also commits to ethical sourcing and conflict-free metals, fully disclosing that their products are derived solely from recycled or scrap sources.
• Thomas provides an online directory for scrap metal suppliers across the U.S. and Canada, and allows users to input various parameters such as quality certifications, origin of manufacture, and company diversity (Ex. minority and women-owned suppliers). Note: You will need to create a Thomas account to access this directory.

RECYCLED PLASTIC

Recycled plastic used in construction offers a building material that has a lower carbon footprint and is stronger than brick, all while tackling our plastic waste problem (367 million metric tons produced globally in 2020). Note: Plastic loses its molecular integrity each time it is processed and recycled, meaning recycled plastic must be mixed with additives to regain durability and performance to be used as an effective building material.

• Tangent Materials manufactures HDPE-based lumber, sheets and boards for residential, commercial and structural applications. Made primarily from recycled milk jugs and laundry detergent bottles, Tangent Materials products are GreenCircle “Closed Loop Product” certified and help to reduce landfill waste and preserve forests and the wildlife that depend on them. And unlike wood and PVC, Tangent Materials structural lumber doesn’t need to be chemically treated, avoiding the release of harmful pollutants into the air, water and ground. You can find Tangent Materials green product certifications on their website.
• Arqlite, a member of the U.S. Green Building Council (USGBC), turns plastic waste (traditional #1 – #6 plastics along with the mysterious #7) into Smart Gravel, a mineral stone alternative that can be used as an aggregate in concrete, a substrate for hydroponics and as drainage and decoration for landscaping and gardening. Smart Gravel is three times lighter than mineral stone, has ten times better thermal and acoustic insulation properties, is long-lasting and proven to not break down into toxic leachate or microplastic particles. Arqlite provides their leachate and toxicology reports online.

BIO-BASED AND RECYCLED INSULATION

Insulation is one of the most important factors that play into your home’s energy efficiency. Proper insulation regulates indoor temperature more effectively, minimizing drastic fluctuations thus helping you conserve energy and lower your heating and cooling bills.

• Greenfiber®, manufactured in the U.S., is made from post-consumer paper fiber and free from toxic substances such as formaldehyde and asbestos. Greenfiber® uses 13 times less energy to manufacture than fiberglass insulation and cellulose-based insulation has been proven to reduce heating and cooling bills by up to 25% and sound power by up to 60%.
• Icynene is a foam insulation that sprays into building cavities and expands as a solid, spongy mass, effectively sealing off cracks and crevices. Some icynene products are partially made from castor oil (from the drought-resistant castor oil plant, Ricinus communis) while other products are starting to include recycled PET content. While icynene is an eco-friendly insulation alternative that adds to the energy efficiency and structural integrity of a home, it is far more expensive than fiberglass and is so airtight that it can impede on proper ventilation.

ENERGY STAR offers a helpful guide for choosing the most appropriate insulation type depending on your project and skill level, as well as a list of ENERGY STAR certified insulation products.

HEMP

Hemp (a variety of Cannabis sativa L. and the non-psychoactive relative to marijuana) is a versatile crop grown specifically for industrial and medicinal uses. For centuries, dating as far back as 8000 BC, hemp has been used in human civilizations to make paper, food, oils, rope, clothes and other textiles. Compared to trees, hemp grows roughly 50 times faster and requires less area to grow. Its biodegradability, durability and high capacity for storing carbon makes hemp a promising green building material.

Made from mixing water and natural lime with hemp hurd (the inner woody core of the hemp stalk), hemp bricks or “hempcrete” are as hard as stone and can be used as non-load bearing infill for walls. Hemp hurd can also be used to manufacture panels and fiberboard to be used as interior and exterior insulation and flooring. Hemp building materials are durable and long-lasting, fire, pest and mold resistant, and possess efficient acoustic and insulative properties.

• The U.S. Hemp Building Association (USHBA) offers an online Hemp Structures Map to showcase real-life building projects around the country that have utilized hemp in their construction as well as a Supply Chain Map to help people find hemp suppliers. USHBA offers webinars and runs a members forum for anyone seeking guidance on building projects and hemp-related curiosities.
• Hempitecture offers USDA certified biobased products including HempWool for thermal insulation (along with Vapor+Air controlling membranes that support optimal HempWool performance), Natural Fiber AcoustiBatts for acoustic insulation, and hempcrete blocks for non-load bearing construction.
• Americhanvre, a member of the U.S. Hemp Building Associatoin and the National Hemp Association, is a full service hemp building material installer whose services include project consulting (over the phone or virtual), supply chain and delivery logistics, installation for new builds and retrofits, and project management for an organized and efficient building process.

ROOFING

The roof above your head can do a lot of good for the Earth below your feet. From reducing landfill waste to minimizing heat island effects and energy costs, an eco-friendly roof can play a critical role in your sustainable home.

• Enviroshake manufactures composite roofing tiles that are 100% recyclable at end-of-life and made from 95% recycled content including post-industrial plastics, natural fibers and elastomers. Environshake products install with less waste than conventional shingles, imitate the look of natural cedar and slate, and are mold, pest and weather resistant.
• Brava, another synthetic shingle manufacturer, also uses recycled content in their products.
• The Cool Roof Rating Council (CRRC), a 501(c)(3) nonprofit organization, develops and implements credible methods for rating the radiative properties of roofing and exterior wall products. The CRRC offers a rated roof product directory that allows users to input specifications such as thermal emittance and solar reflectance.

ENERGY EFFICIENT WINDOWS

When it comes to energy efficient windows, installation and construction are key. Properly installed double or triple-pane windows offer the greatest insulation and temperature control, lowering your energy use and utility bills. Windows with a low-emissivity (low-E) coating have higher efficiency ratings as they minimize the amount of infrared and UV rays passing through while still maintaining optimal natural light and consistent indoor temperature.

• Pella Windows & Doors offers ENERGY STAR certified windows and doors that excel in energy efficiency and climate control as well as hurricane impact resistance. Pella products include wood, fiberglass and vinyl framed multi-pane windows with a low-E coating and the use of Argon in between panes to boost insulation.
• The National Fenestration Rating Council (NFRC) provides an ENERGY STAR product and manufacturer search for energy efficient windows, doors and skylights. A product’s NFRC label highlights various energy performance ratings such as air leakage and visible transmittance, allowing consumers to easily compare energy efficient products.

Sustainable Interior Design

Incorporating sustainable, non-toxic materials into your interior design supports safe indoor air quality and occupant health. Here are some brands to consider when putting together your interior space.

INTERIOR PAINT

• Smog Armor’s Breathe paint is a non-toxic, zero-VOC (Volatile Organic Compounds) water-based paint enhanced with an absorptive mineral that attracts airborne chemicals, VOCs and carbon dioxide. Smog Armor products are lab tested and proven to reduce indoor air pollution by up to 95.1% in one hour.
• Real Milk Paint is a bio-based zero-VOC paint made from 100% all natural ingredients including casein (a protein found in milk), lime, earth pigments and a plant-based filler, meaning Real Milk Paint is both non-toxic and biodegradable. In fact, the Real Milk Paint states their products can be disposed of safely in your garden and compost.
• Benjamin Moore Eco Spec paint, made from 100% fast-drying acrylic, offers zero VOCs and emissions, is Green Seal certified and certified asthma and allergy friendly.

CARPETING AND FLOORING

• Forbo offers flooring products partially made from recycled materials, with some individual products consisting of as much as 89% recycled content. All Forbo products are made from safe and 100% traceable raw materials and from 2004-2021, Forbo reduced the average carbon emission per square meter of product by 70%. Forbo has over 10 years of annual sustainability reporting in adherence with Global Reporting Initiative (GRI) guidelines, as well as Environmental Product Declarations (EPDs) for 47 flooring ranges. Forbo provides their annual sustainability reports and publications on their website.
• FLOR eco-friendly area rugs and carpet tiles are manufactured from 100% renewable energy and made from recycled-content fibers such as ECONYL®, derived from fishing nets and textile scraps. FLOR has created carpet backings that are carbon neutral, with some newer versions being carbon negative, and the company continues to use and explore raw materials that use plant-derived carbon or sequester carbon. FLOR offers a Return & Recycle program for customers to send back their FLOR rug once it has reached end-of-life; FLOR then recycles these old carpet tiles into new ones (FLOR recycled over 74,000 carpet tiles in 2021).

FURNITURE AND HOME DECOR

• Coldharbour Tiles, based out of Europe, creates luxury decorative wall tiles made from recycled fishing nets. Coldharbour tiles have a lower carbon footprint compared to traditional ceramic tiles produced from a GHG-intensive glazing process.
• Sabai, family-owned and operated in High Point, North Carolina, builds luxury, custom furniture made from natural, recycled and upcycled fabrics, FSC-certified wood and CentiPUR-US®-certified foam. 90% of materials are sourced within 100 miles of production. Sabai also encourages “Repair, Don’t Replace” by selling individual components to give old furniture new life. Sabai offers their Revive program that allows customers to trade in and buy second-hand, newly refurbished sofas for up to 30% off the original price.
• Another stand out eco-furniture brand, Medley, manufactures a variety of furniture pieces from the bedroom to the office. Their products are only built with certified sustainable materials such as:
  • FSC-certified low-VOC plywood, bamboo and domestically-sourced Alder, Walnut and Maple hardwood
  • CentiPUR-US®-certified foam and organic natural dunlop latex (derived from the sap of rubber trees)
  • OEKO-TEX® Standard 100 wool
  • Natural fibers such as cotton and jute
  • Greenguard Gold-certified or OEKO-certified synthetic fibers
  • USDA-certified 100% bio-based polishes

Needless to say, Medley goes above and beyond to ensure every inch of their products is made with the best quality, eco-friendly materials. Medley furniture is made-to-order in Los Angeles, California.

• Remember: Before you buy new, try finding gently used furniture in your community. FreeCycle, Craigslist, Facebook Marketplace, GoodWill and your local thrift store are all great places to hunt for used furniture.

LIVING WALLS

• LiveWall, a BBB accredited business, designs and installs interior and exterior green walls as well as pre-assembled mobile green walls that serve as easy-to-move-around room dividers. Incorporating plants into your living spaces can help filter irritating airborne particles, absorb CO2 and create a natural cooling effect (saving HVAC costs), support mental health and productivity, and support surrounding biodiversity.
• Ginkgo Sustainability is another credible manufacturer and installer of living walls as well as living roofs.

Additional Resources

As you pursue your sustainable home project, two online resources that are a must-save on your browser are:

• Green Building Supply, a directory for finding sustainable, non-toxic building materials and home products. Users have access to product reviews, Material Safety Data Sheets, Q&A, maintenance and installation guidelines, and instructional videos. The products included on Green Building Supply meet one or more of the following criteria:
  • Safe and non-toxic
  • Renewable, recycled or upcycled
  • Energy efficient and ENERGY STAR compliant
  • Meet or exceed US or European environmental standards
  • Good reputation in the industry
  • Personally tested by Green Building Supply
• Rate It Green, another green building directory, allows users to find sustainable products and services across a vast range of categories. Rate It Green also serves to connect people to green builders and green building organizations, as well as act as a network for exchanging green building information and experiences. The Rate It Green Community organizes groups by location, certifications and labels, affiliated industry organizations and government agencies, among other specifications.

Summary

Advancements in material science and the emergence of green building alternatives are minimizing the environmental impact of residential construction and improving the way we live. Now, it’s possible to build a sustainable home from a diversity of materials and sources. Here are some key green building materials to consider when constructing or retrofitting a sustainable home:

• Reclaimed lumber
• Recycled steel
• Recycled plastic
• Bio-based and recycled insulation
• Hemp bricks, panels and insulation
• Energy efficient windows and doors
• Recycled-plastic roofing shingles
• Zero-VOC paints
• Recycled-content carpeting and flooring
• Ethical and green certified furniture
• Living walls and roofs

To learn why green homes matter to today’s homeowners and the benefits that a sustainable home offers, read our article, Green Realtor® Guide: Marketing Eco-Friendly Homes and Sustainability.