| |
We tend to remember demolition
projects in terms of large buildings, with implosions that draw
crowds of onlookers and television cameras and bring down the structures
in carefully controlled clouds of dust. Most demolition, however,
concerns small structures or only parts of structures. When the
old, cracked sidewalk of Main Street is broken up to enable the
pouring of a new one, that's demolition. When the concrete supports
of the Old Town bridge are replaced, that's also demolition. Hydraulic
hammers and breakers, attached to big excavators or scudding skid-steers,
announce demolition. For many demolition projects that excavation
and grading contractors come across, a single dump truck (even a
1-ton pickup) could handle the debris, and the demolition is not
the entire job but a prelude to new construction.
Before filling that truck,
consider what the demolition has provided. "Debris"
can be valuable; for some demolition companies, the value of what
they dismantle covers the cost of the job. One of the world's
leading demolition specialist companies is Brandenburg Industrial
Service Company, headquartered in Chicago, IL. "It makes sense
to recycle the products of demolition," asserts Bill Moore,
a vice president at Brandenburg. "To simply throw away the
unwanted materials is usually an unnecessary waste. The debris that
used to be considered useless can now extend its useful life by
providing basic materials for contractors, for new construction
at the same site or elsewhere." Brandenburg inspects a potential
demolition site and considers its salvage value before committing
to the work or making cost estimates for the client.
What
could you find in the debris? What can be recycled? Some states
have laws that require contractors to post a bond that will be returned
to them when they prove they have reused a certain percentage (as
high as 50% in some cases) of the debris from demolition and construction.
"Reused" might involve the contractor directly or it
might mean that materials from the site have been sent to an appropriate
place for recycling or acceptable disposal. Call and Haul is a company
(started in California but now expanding to Colorado, Texas, and
Washington) that will haul construction debris and household junk.
"Everybody from contractors to little old ladies has a need
for one or all of our services at one time or another for construction
or maintenance of a property," remarks Dean Rodatos, who has
had the company for four years. "We have our own grinders
for recycling concrete and wood. Our workers separate materials
at the job site. They know what is recyclable, sellable, and reusable,
so they save the site contractor time and money." Rodatos
explains that a material such as sheetrock (that most people break
down and perceive as nothing but waste) is used again for the manufacture
of garbage cans or park benches, and it can become a useful ingredient
of fertilizers.
 |
| Some
wood can be reused, but much of it can only be turned into chips. |
What
can you expect from a debris handling service such as Call and Haul?
It does all the loading and cleanup, calls half an hour in advance
to let the customer know they're on their way, and recycles between
40% and 60% of everything they pick up. The reservations line is
available 24 hours a day, and the company is insured and bonded.
If your demolition project is not an everyday occurrence, it seems
worthwhile investigating the local availability of such services.
According to many contractors
and haulers, the sorting and disposal of construction debris is
a business of its own, with expertise and equipment that are specific
to the task. CornerStone Material Recovery, operating from Richmond,
IL, hauls debris for building developers and demolition contractors.
"The builder should find a removal firm to handle his debris
responsibly," advises Steve Clements, vice president of the
company. (Don't underestimate that word responsibly,
we have learned from nationwide conversations.) "We recover
materials during collection but also handle debris removal. Some
materials recovered are of little or negative value. Even woodwaste
can be a problem to unload at a processor. Involving the builder
in sorting to various containers will cost him more in handling
fees, which will increase subcontractor prices to your bid. We have
been recycling debris for our clients for more than 10 years so
that they can stick to what they know best too: construction, demolition,
excavating, and grading."
Ask Some Questions
Before the Demolition Starts
 |
| Demolishing
and dismantling unwanted structures is only part of the job. |
If demolition or dismantling
is part of your project, and you are going to do it yourself, get
some answers before your workers move in. Are the structures (or
parts of structures) to be demolished occupied and used at the moment?
What effect could demolition have on adjacent structures? That is
especially important in residential or commercial, urban projects.
Are there any portions that should be retained? Is there a book
value of the structures to be written off? What is the value of
the vacant space provided by the proposed removal work? Is there
an alternative to removal of the structure? There are other questions,
obvious ones, concerning the equipment to be used, obstacles to
be avoided, local regulations concerning noise levels and environmental
issues, the safety of workers and bystanders, and the best method
of disposal of the debris. Do your workers know how to handle the
demolition? It is probably not simply a matter of swinging a sledgehammer
or ramming a hydraulic breaker into old concrete.
F.M. Frattalone Excavating
& Grading Inc. in St. Paul, MN, has found an increasing number
of demolition projects over recent years. Its ability to do that
work well has depended on its available equipment, which includes
cranes with 250-ft. booms, hammers, crunchers, shears, and clams
of all shapes and sizes. What happens to the debris? "In this
day and age you must recycle as much as possible," maintains
Tony Frattalone, president. "It can get you a project by how
much you say you can recycle. We recycle concrete, bituminous, copper,
aluminum, steel, and rubber at our demo sites. We also run a crushing
spread that we make [by recycling] number-5 and -6 gravel with concrete
and bituminous. Site debris like wood, roofing, and insulation normally
goes to a sanitary landfill. In the state of Minnesota, some people
feel we are behind the more southerly states when it comes to reusing
or recycling materials, but we are getting there." Among demolition
projects handled successfully by this grading and excavation company
(with good foresight and planning, it seems) have been a grain elevator,
mill ruins, an out-of-date museum, the Coffman Student Union at
the University of Minnesota, and the retailer Montgomery Ward in
St. Paul.
If your excavation or
demolition involves asphalt, you can be virtually certain that it
has value as today's road construction programs continue.
In fact, most of what is demolished from old roads and streets can
be used for new ones. "We think asphalt is 100% recyclable,"
comments Jerry Barr for B&B Paving, based in Bismarck, ND, and
working all over the western states. "We don't have
the recycling machinery ourselves. We pick it up and take it to
our asphalt producer, who uses it all - as far as I know - for
new mixtures in new roads." Concrete, too, often becomes part
of a new road once it has done its job on an old one. There are
efficient portable crushing systems available from several manufacturers,
but their purchase seems to be justified only when they are likely
to be in use for most of the year.
At earthmoving or road
construction sites, a portable crusher set up nearby could be cost-effective;
it might not be for the renovation of a single house or similar
small project. Grasan produces a concrete/asphalt recycling plant
that can handle 600 tons per hour. The rubble-crushing system includes
an impact crusher plant, conveyors, an electromagnetic separator,
and a screen plant. The manufacturer advises that, for construction-and-demolition
debris, the user might need picking stations to separate plaster,
drywall, electrical wire, and other materials. Plants such as this
can manage your debris well. As mentioned, their use will depend
on your volume of debris. One contractor suggests that a group of
contractors in the same community might join together and purchase
a concrete/asphalt recycling system to be used by all of them.
Construction debris can
be dangerous; at most sites it consists of broken, sharp, oddly
shaped pieces. "Safety pays," stresses Raymond Passeno,
vice president of Bierlein based in Midland, MI. Bierlein has been
providing demolition, dismantling, environmental services, and asset
recovery since 1957. Earthwork (sometimes on a massive scale), site
preparation, and development also have been part of its business.
"When Bierlein removes a structure from a site or dismantles
the interior of a facility, the service is performed quickly, safely,
and with minimum business interruption," notes Passeno. "Safety
is a companywide commitment for us. We have an exclusive in-house
safety and training staff. From standard written to site-specific
prejob training and onsite controls, Bierlein believes in and practices
safety." This specialist's safety programs apply to
both equipment and personnel. The equipment must adhere to strict,
computer-monitored maintenance schedules and equipment replacement
policies.
Techniques to Suit
the Application
 |
| Experts
say that today most construction debris can have a practical
use. |
 |
| Careful
preparation before inside demolition will make the job easier
and more profitable. |
 |
| Attachments
available for excavators make demolition a precise application.
|
Demolition
today, then, is not like yesterday's variety. One contractor we
spoke to was surprised at the usefulness of skid-steer loaders in
demolition. "Skid-steer loaders? How can little machines like that
help you make a profitable demolition?" He had never heard of "top
down" demolition. For many structures requiring renovation, such
as old bank buildings, hotels, schools, and public offices, the
demolition starts on the top floor and works its way down. Skid-steer
loaders, with their compact size and good maneuverability, work
on the interior before the shell is attacked by larger machines
and attachments. The skid-steers help dismantle furnishings and
objects such as partitions and screens, timber, floors, and non-load-bearing
walls. Among the more than 135 million tons of building-related
construction debris in North America each year, there also will
be doors, windows, and plumbing fixtures in addition to the gypsum,
bricks, metals, and plastics you'd expect. If you include demolition
in roads and streets, you'll find plenty of concrete and asphalt
that can be reused. It's just not the same as when a big ball smashed
through the outside wall and destroyed everything in its path. Today's
demolition emphasizes precision in the dismantling and recycling
of useful materials; the contractors save anything that can give
them added value from the job. When the job is renovation, the owner
might appreciate your contracting to remove and dispose of everything
unwanted, including office furniture, computers (ancient to the
owner but possibly useful to somebody less demanding), lighting
fixtures, and flooring.
"The vast majority
of demolition projects result in recycling," observes Brent
Blanchard, operations manager at Protec Documentation Services.
Headquartered in Rancocas, NJ, Protec has been a consultant in this
sector worldwide for 30 years. "Economics drive the decisions
made by contractors about recycling. We have found that most demolition
projects, big and small, include three types of debris. There are
those that are put back into the new structure because of their
historical importance or intrinsic value; that might include brass
lamps or teak furniture, something of the past we like to preserve.
The second group comprises the recyclable debris, like cement, rebar,
aluminum and glass. The third group consists of debris with no value.
That could include clothing abandoned at the site, wood unsuitable
for reuse, things like that. That type of debris goes to the landfill."
Blanchard mentions three reasons for recycling usable debris that
should ring a bell with most contractors: It keeps down the costs,
it boosts up the profits, and it preserves a good reputation for
the contractor. The latter can be most important when it comes to
permitting and being awarded public contracts.
Getting Local Help
Your local landfill operator
can be a big help. Regulations vary from community to community,
and you should be aware of debris that you cannot dispose of at
your local landfill. This might be especially important for small
contractors whose jobs seldom involve more than a truckload of debris.
The landfill will expect you to sort your debris, and in most places
it will pay you to do so. We spoke to Sheri Shoopman, who manages
a landfill in rural Montana that serves several local towns, each
with a population of less than 5,000. "We do not charge customers
for unloading inert brick, dirt, and rebar-free concrete," she points
out. "Contractors bring that separately. Why would they mix it with
the other debris when they don't have to pay for it?" At that landfill,
household solid waste and construction debris other than concrete - things
such as wood and old kitchen cabinets cost the contractor 2 cents/lb.
Asphalt is $3/ton. They try to put the asphalt tiles in with the
crushed concrete to make roads for the landfill itself. A crusher
comes to the landfill once a year to handle and recycle the concrete.
"Actually the crusher has a magnet on it that can pick out the metal,
so we're not always strict about rebar," comments Shoopman. "The
crushed concrete is then used for building roads." At the landfill
for a larger community, there might be a crusher on-site permanently,
and the demand for road materials seems to remain steady in most
parts of the country.
There are some wastes
that are not accepted at every landfill, and you should find out
about your local conditions for that. Among the common wastes not
accepted are material containing polychlorinated biphenyls, dredge
soils, incinerator waste, contaminated soil, asbestos, fly ash,
and any wastes that are "listed" or "hazardous."
You could have some of those. There are also characteristic
wastes, which means they are ignitable, corrosive, reactive, or
designated as toxic by the Toxic Characteristic Leachate
Procedure. If your debris contains anything resembling that, the
landfill probably will refuse it. You also should have been told
by your client that your debris would contain them because the danger
from, say, ignitable wastes is not only to the landfill but to your
workers. As in so many aspects of construction, do your homework
before you start.
"We
find that materials damaged by fire and smoke are seldom recyclable,"
warns Paul Young, project manager at Big Sky Disaster Restoration
in Billings. "The houses we renovate are not strictly demolished,
not by us anyway. We are asked to restore properties that have been
damaged by external forces, usually fires." Young makes a
good point; there is a difference between planned demolition and
unplanned destruction. Most of our readers will encounter the planned
variety, so they have a choice about how to dispose of or reuse,
windows, doors, cabinets, and carpets. Prices for metals, plastic,
paper, and glass have not changed much in the last year, with some
types going up a little in value and others coming down. One caution
we have received more than once is that all plastic is not the same.
There are different plastics and different needs for each type;
you'll have to get help from a local expert if you find much
plastic in your debris.
"We can't
recycle much of the wood we recover," comments Marsha Mitchell,
who works mostly on excavation and trenching but has occasional
demolition work because she and her husband Keith own a large excavator
whose boom can reach the roof of the average old house. Most of
the structures they have demolished are old (as much as 70 or 100
years), often derelict, houses that nobody wants to buy because
they are either in bad condition or inaccessible - in the middle
of a few thousand acres of land no longer irrigated or farmed. "Old
wood and new wood have different dimensions too. Two-by-fours aren't
always two by four," she relates. "We have few contractors
who want to use the old stuff. They say it gives them too many problems."
Safe Removal of Debris
From High Places
 |
| Equipment,
such as this concrete/asphalt recycling system, can be set up
at demolition sites if the quantities of debris justify it. |
Earlier we mentioned
top-down demolition. One of the important tasks in many demolition
or renovation projects is getting the waste materials "from up there
to down here" without endangering people in the street or anybody
below. Telescopic handlers and some aerial work platforms can serve
to bring debris down to the ground, but there is always the risk
of dropping some of the load too soon, which is when accidents happen.
Among the most popular vehicles for debris removal from high places
are chutes. They contain the falling debris and enable contractors
to follow local or federal guidelines for safe work. Don't ever
drop anything more than 20 ft. to the ground.
A basic chute system
(such as those made by Superchute) includes straight lengths of
steel tube or plastic about 4 ft. long and sections with openings
that can be positioned at various heights to accommodate such apertures
as the windows of an apartment building. At the top of the chute
there is a funnel-like section that acts as a hopper. "Our
chutes have diameters of 18 to 36 inches," explains Brian
Alton at Superchute. "The system can range from just a single
story to about 200 feet in height. Some chutes available are welded
tubes that can take up a lot of room during transportation, but
we have units that can fold as flat as a sheet of plywood and lie
on the bed of a pickup - about 20 of them at a time."
Alton recommends that contractors rent chutes for specific projects
rather than try to make their own systems. The time required for
an acceptable design and the cost of materials can make the homemade
versions more expensive, especially if they are seldom used. Hoists
for setting up the chute system are available for rent too.
We are going to create
debris when we break, dismantle, or demolish anything. To make the
project more profitable, legal, and environmentally acceptable (as
well as enhancing the good name of our business for future contracts),
we should decide what is going to happen to the debris. Whatever
the solution, it is feasible today. Whether we do it ourselves or
have another contractor manage disposal for us, it should be a positive
rather than negative aspect of the job.
Paul Hull writes on
construction and environmental topics for several international
magazines.
GEC - January/February 2003
|
|
