If anyone is on the verge of a renovation project or contemplating demolition of a residence, I urge you to consider practicing deconstruction.

"Deconstruction is the dismantling of a building in such a manner that its component parts can be (in the best scenario) reused. A process of carefully taking apart components of a building, possibly with some damage, with the intention of either reusing some of the components after refurbishment or reconditioning, or recycling the materials. It may be undertaken during refurbishment, when adapting a building for new use, or at the end of its life." 

This process diverts incredible amounts of waste from the landfill. Data on building and site related construction and demolition activities is not incredibly recent, the latest available is 1996, but in that year 136 million tons of debris was created from construction and demolition activities. Forty three percent of that waste was from the residential sector, 58.5 million tons of waste. From this data it was shown that 20-30% of the debris was recycled, with the rest going to construction & demolition landfills of municipal solid waste landfills. Deconstruction, on average, is able to recover 75%-95% of the site and building if local markets are available.

Deconstruction contractors are available and there is information out there to help anyone at any skill level get involved in deconstruction. This process uses all three R's: reduces landfill waste, REUSES much of the material in its existing form (lowest energy required, no processing involved, mostly just transport) and when materials are not reusable, they are recycled.

I'm curious to hear people's experiences with deconstruction: successes/issues or if you're looking for resources. Most cities at least have a Habitat for Humanity ReStore, with people who are able to come to your site and inspect what you have and let you know if they will be able to sell it. A common thing is cabinets: no matter how much grief they have given you or how badly you want your renovation to start, please, PLEASE don't take a sledgehammer to them. They can be reused! and of great assistance to someone else. Keep that in mind in your all your projects!

This is a good message. I am just about to take down my house. Demolition would be $8000 and done in a week. Deconstruction will be more like $12,000 and will take a month. The costs are only minimally offset by reduction in tipping fees and income from salvage. It just seems like the right thing to do though, to make sure as many of the materials as possible can be reused in some capacity.

It won't be done in a large scale unless it is cost competitive and easier to do. I recall a pretty significant upcharge for deconstruction by a reuse center. If one did much of the deconstruction himself, who would want old siding, shingles, old inefficient windows, maybe some decent wood framing, and concrete block?(probably have to be ground up)?

A lot of research is being done into the cost differential between deconstruction and demolition. So far it seems to depend on the building and the types of material that are able to be recovered that determines a positive cost-benefit ratio. Right now, becuase deconstruction of reuse of secondhand materials is not a very large or widespread industry and the people trained to do it are small in number it is going to be more costly. But the avenues for reuse are there. Old aluminum siding is reclyclable, shingles are being ground up to be used in hot mix asphalt applications (depending on their composition, some contain asbestos), and concrete block often gets downcycled to be reused in concrete mix. Habitat ReStores take things like framing and old windows, but I know they are one of the harder things to sell, because like you said they are innefficient. Some uses are in outbuildings or greenhouses, I've also seen art studios use old windows for interesting projects.

These avenues are available and why it is more convenient to use a deconstruction contractor or company, because they already have the connections in place to get the materials to the retail market. Doing a job like that yourself requires a lot more creative thinking and ambition to get the materials to where they will be used. These are important issues, and limitations, to deconstruction currently, I agree. But these issues will be abated as the industry grows. Locally your city government could help this industry out by raising disposal fees and there are other policy changes that are being undertaken currently.

The main product that I've seen reused (not recycled) in deconstruction out here in California and close to Mexico is the lumber.  I think this has been due to the fact that Mexico doesn't have a large lumber industry apparently and the workers that were used to take apart the buildings were from Mexico (and thus paid less) so the company doing the deconstruction could take apart the building, salvage the lumber, load it up and truck it across the border and resell it at the lumber yard while making a profit. 

In California there is a big push to recycle more and more material and here in San Diego City, where we're running out of dump space, there is now a mandate to recycle more and more construction debris or pay a larger and larger fine for not doing so.  From what I've seen what is done is the concrete goes in one area and the wood in another.  I haven't seen gypsum board being recycled yet (and with the Chinese drywall scare it's likely it won't be happening soon) and I haven't seen asphalt shingles being saved either although for commercial projects that might be different.  The concrete is easy to recycle and the wood is ground up at the dump and composted so I'm guessing all the metal has to be removed from it, but maybe they use magnets at the dump to pull out the ferrous metals.  Glass can be recycled also, of course, but there's not much glass in a construction project and I have yet to see a special area for recycling of it.

As was pointed out earlier in the thread a lot of the materials in an old house are, well, old and not too desirable to use in new construction especially with the increased energy efficiency requirements.

Deconstruction is a fantastic practice when the materials are worth salvaging. The cost differential must incorporate two factors that have not been mentioned so far. The first factor would obviously be the value of the products that are being salvaged. The second cost to factor is the cost savings associated with not dumping the waste in landfills.

Our company has one of the only EPS melting / recycling machines in Canada. We constantly have contractors and builders bringing us scrap EPS from construction sites. Although the business of melting EPS into a raw plastic that can be reused to manufacture other plastic materials is not profitable, the cost savings of not bringing the scrap EPS to the land fill does save the contractors a significant amount of money. In this situation, it is cost effective to recycle the EPS as opposed to dumping it. The offset waste disposal costs would also apply when a site is deconstructed as opposed to being demolished.

Even if the cost of deconstruction is slightly higher than the cost of demolition, the environmental impact of reusing vs. dumping is more valuable than anything.