Cleaning up after yourself

Proper dismantling is harder than building.

Our tutoring consultant commutes by bus, and one of the stops along the way is an old shopping mall.  It’s a sizable place, but it shut down shortly after he began his job, and was derelict for several years.  Recently a demolition company has stepped in to clear the site for new building.

The result at first looked something like the pictures in the news from war zones: walls gone, allowing a somehow indecent look at rooms inside; fittings dangling or piled on the ground.  Then the buildings themselves were dismantled, leaving several piles of concrete blocks, other piles of piping, great mounds of various materials sorted by type.  It’s somehow unsettling to see an overpass (leading from the nearby highway) reduced to rubble.  At the moment there are piles of gravel on the site; it appears that most of the building material has been hauled away.  We don’t know when building is scheduled to start.

It struck us that nowadays demolition is probably a harder job than building.  Taking things apart carefully, so that hazardous materials can be safely disposed of, must be harder than putting them together.  And there are many materials now known to be hazardous that were just normal ingredients in life decades ago.  Indeed, there is now a major industry dealing with remediation of old industrial sites and toxic waste dumps.

As the history of building goes, this is a relatively new thing.  Up until the environmental movement of the second half of the last century, useful parts of a demolished building were kept and anything else just thrown away.  Sites that became derelict eventually became mounds of earth, to be dug into by later archaeologists.  To be sure, there were fewer hazardous materials before the flowering of Chemistry in the nineteenth century.  But not none: Medieval cathedral roofs were covered with lead as waterproofing, and arsenic and mercury found their uses.

So it makes sense to us nowadays to consider the end of a building when planning for its start.  We’re not sure what regulations or practices may already be in place.  Neither do we know what form such considerations would take, beyond a careful identification of all substances used.  Planning on buildings to last only a specified period of years, and making them easy to dismantle then, might be a good idea from a strictly economic/engineering point of view.  It could be easier than renovating them when technology changes, or when other conditions change (the need for better insulation and more powerful air conditioning, for example).

Of course it’s hard to think of demolishing something you’ve put your heart and expertise into building.  And making a building easier to take down might possibly make it less sturdy during its life.  Certainly it’s difficult to say just how long many buildings might last; some hang on for centuries, even if that wasn’t intended from the start.

In what may be a comment on priorities, although the shopping mall is gone, the three-story parking garage has been retained.