What's the best affordable sustainable siding option? Any thoughts on roofing materials and gutters?

Asked by Wendy Jebens, Carrboro, NC

Over the next few years, we're probably going to have to replace our siding (we currently have Masonite), roof and gutters. For siding, is HardiePlank the best sustainable siding option that's affordable? (We can't afford sustainably forested wood siding.)


Any thoughts about roofing materials? I have heard about solar tiles, but don't know whether they are economically efficient and can handle high winds.


And finally, any suggestions for sustainable gutters?


Carl Seville

Answered by Carl Seville

Decatur, GA

SK Collaborative

February 22, 2007

Mineral-fiber or cement-based siding products like HardiePlank are inexpensive and very durable. 

  • They are considered sustainable because of their extremely long lifespan.
  • They require little maintenance and rarely need replacement.

HardiePlank is the brand name for mineral-fiber siding manufactured by the James Hardie company. These siding products are available in lap siding, sheets, shingles and trim designs. Similar products are available from other manufacturers. 

[ Check our green siding Q&A to see what homeowners and contractors are saying about the pros and cons of vinyl siding, fiber cement, etc.  ]  

Sustainable roofing

There are a wide variety of sustainable roofing products on the market to cover various needs. In hot climates, you should look for a reflective roof that reduces the amount of heat transmitted through the roof into the house. This can be a metal roof, asphalt shingles or tiles, to name a few options. Another consideration is the material content.

Some roofing materials are manufactured from recycled products such as rubber; others, such as asphalt and concrete tiles, are fully recyclable.

The most sustainable roof is one that uses the fewest natural resources to produce, and is manufactured locally (reducing the need for transportation and its associated pollution), energy efficient and long lasting. Consider your personal needs and how you can match them to as many of these criteria as possible (it is unlikely that you can meet them all).

You mentioned solar shingles, which generate electricity when the sun shines on them. This technology, called photovoltaic, is becoming more available but usually involves installing separate panels on top of the roof. If you are considering solar panels, it is important that you first reduce your home's electric load to a minimum through insulation, air sealing, HVAC upgrades, lighting and appliance improvements, and so on. There is not much point in investing a lot of money installing solar panels on a house that is otherwise inefficient.

When you consider roofing and siding materials, keep in mind that the primary goal of these products is to keep rain out of the house. Roof shingles help keep the house dry by shedding water.

  • Many people believe that the siding on a house is what keeps it dry, when in fact, the siding does not keep the rain out, rather the "drainage plane" behind the siding does that job.
  • This drainage plane consists of felt paper or housewrap installed shingle style, each layer overlapping the layer below to shed water.
  • Every window, door and hole in the drainage plane must be sealed with flexible flashing tape to shed water over the layer below. Only a properly installed drainage plane will effectively keep water out of the house, maintaining a safe, healthy and durable structure.

The Energy and Environmental Building Association publishes the Water Management Guide, an excellent resource that demonstrates how to keep water out of residential buildings. In addition, manufacturers such as Tyvek and Grace provide excellent instructions for installing their flashing products.

Sustainable gutters

Gutters are a subject of debate among building professionals. When installed properly and well maintained, gutters can be a great help in keeping water out of a structure. When installation is compromised and maintenance poor, however, gutters can become a detriment, directing water into rather than away from a structure.

When a building is on high ground with good drainage, it is often possible to eliminate gutters.

When gutters are required, select the most durable and recyclable material available, such as aluminum or copper, and make certain they are installed properly—the downspouts should terminate at least five feet from the foundation walls. Also consider including a rainwater collection system and using that water for irrigation.

Tagged In: fiber cement siding, roofing, siding

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