What's the least expensive way to replace the siding on a house? Vinyl, of course. And, according to the latest report from The Freedonia Group, a market tracker, vinyl siding easily leads residential cladding in market share, with 37% of the total siding market.

But in an increasingly green-conscious building industry, one factor that has counted against the product is how little of it comes from recycled material.

When recycled material is used, it's usually pre-consumer, i.e., “it came from the plant and never shipped to a retail store, or ever got touched or installed,” says Kevin Riley, owner of Riley Recovery Systems, a North Carolina company that collects industrial scrap, including vinyl, and processes it for recycling. Most vinyl siding tear-off — post-construction scrap — ends up in landfills.

CHALLENGES TO RECYCLING Riley will pay by the pound for post-construction vinyl — tear-off — but as yet he has few takers.

A siding contractor recently came to him with vinyl scrap from a condo re-siding project. In that case, the large amount of material made recycling worth it. (Riley pays 15 cents per pound, delivered.) Most installers, though, are unlikely to take the time or trouble to deliver vinyl tear-off to a recycling facility.

There are few such facilities — the Vinyl Institute lists 200 companies recycling scrap vinyl siding — and even if the recycling company paid, the load size is small and the delivery distances typically inconvenient. Which is why most vinyl siding tear-off ends up in landfills.

PUSHING THE ISSUE Siding suppliers say the problem is not technology but logistics. It's not that manufacturers can't work with tear-off, it's that the effort involved in cleaning and collecting that tear-off makes it far from cost-effective for contractors, especially those installing small jobs.

Manufacturers such as CertainTeed and PlyGem are including more recycled vinyl in their products, and three years ago CertainTeed began building a network of drop-off sites, at its distributors, for vinyl siding tear-off. Those locations will accept post-construction vinyl “to our specifications,” says siding products manager Brian Kirn.

Response has been slow, but that was true about asphalt shingles before they began to be recycled and some locales mandated recycling. Kirn says that he can envision a majority of contractors participating in vinyl siding recycling five years from now