Mechanizing The Dirty Job Of
Tear-Off Removal
Can Generate Great Profits

How you can reduce this huge direct labor expense.

Written by John Cleasby and Karen Cleasby
Published July/August 1998 in Western Roofing Magazine

Cutting up an old built up roof and removing it’s contents is an extremely labor intensive, time consuming and most often a very expensive process. Mr. Blue advises, "…always keep the material moving and never lay it down until it hits the dumpster." "Avoid handling the same material more than once." " This costs you time and money." The proper roofing equipment used in conjunction with an organized plan of attack will insure that the debris moves continuously to its final destination - the dump trailer.

The first step in an organized plan of attack is to remove any gravel present on the roof. The traditional method for gravel removal has been to use lots of men, lots of gravel brooms (push brooms) and many man hours. In Mr. Blues words, "…get mechanized." One man walking behind a motorized power broom could complete the same job in half the time. A definite cost savings opportunity exists here.

Power brooms range in cost from $750.00 for a simple hand held unit, $3,000.00 for a walk behind on up to $6,000.00 for the tractors with power broom attachments. Most brooms are equipped with a pull start, 5 h.p. engine that runs on gasoline fuel. For smaller commercial jobs and some residential work, a hand held power broom may be ideal. It is small enough to get into those hard to reach areas and is light enough to get to the roof top without the use of a crane or other special hoisting equipment. It can also be used on flat residential roof tops whereas the walk behind power broom or the tractor with power broom attachment are designed to be used primarily on commercial roofs. Contractors that do a lot of gravel removal may prefer a unit in which its sole purpose is to function as a power broom. These units are simpler to operate since there are no removable attachments to contend with, and the cost is generally half that of a tractor with attachments. For large commercial roofing, a tractor with a power broom attachment may be the best bet. It offers more versatility including a roof remover attachment and a dozer blade that is used to remove gravel and tear-off debris. There are several other attachments available that are not directly related to the tear-off process but may be applicable in other realms of roofing.

The second step in this systematic approach to tear-off removal is to cut the roof up into pieces that will fit down a 30" diameter trash chute. Powered roof saws are the norm for cutting a built up roof into manageable sections. Using a roof saw, cut the built-up roof into a checker board design for ease of removal. It is amazing how fast it lifts off the roof deck when cut in this fashion. The advantage of this pattern becomes apparent when walking behind a powered roof remover. The checker board cuts just roll right up.

There are several things to consider when purchasing a roof saw. First and foremost, make sure that the saw is equipped with a remote air intake. Engines require clean air to run smoothly; without it, engines may heat up and brake down. A remote air intake is designed specifically to provide a constant supply of clean air to the engine to keep it running smoothly. We personally have never witnessed a roofing job with no dirt. Hence, our strong recommendation for the use of a roof saw with a remote air intake. Engines are a big consideration as well. All roof saws offer engine upgrades. We suggest going with the maximum horse power you can afford. The reasoning behind this is simple, the higher the horse power the less it has to work to cut through the layers of roofing material. The less the engine has to work, the longer it will last providing it is maintained according to the manufacturers recommendations.

A roof saws cutting blades are worth discussing since there are a few options available. All roof saw blades are made with carbide inserts and are of the same basic quality. What you need to consider here is expense and quality of the cut. The standard carbide blade is the least expensive and the most popular. The Posa Trac variety are considerably more money but give a much smoother cut. There is a Posa Trac I blade that is actually two blades. It has a straight blade and an off set blade that work together to make a smoother cut. The Posa Trac II blade is slightly different in that it is one solid piece with four replaceable tips. The advantage here is that you need only replace the tips instead of the blade. The tips are half the cost of a standard carbide blade. Jeff Wilks of Chambers Master Tool believes that "the expense of replacing the tips could be far less than replacing a whole blade over the long run." According to Mr. Wilks there is no average life of a blade due to the fact that "from one job to the next, the environment changes." There are so many outside variables that affect the life of a blade including the composition of the roof, how often the blade is used and whether or not it is being handled correctly.

Most roof saws have an adjustable lever at the handle for depth control. This allows the user full control of the blade and how deep it will cut. Since all roofs are different, it is not possible to standardize how deep a blade will cut. Hence, the benefit of a depth control lever. This brings us to another critical point. Since roofs are not completely level be very careful when using a double bladed roof saw. Both blades are set evenly and will cut at the same depth. The potential problem exists that one blade may accidentally cut into the roof deck. This is due in part to the fact that pockets and other uneven points are a given with all roofs. In other words, no roof is ever completely level. Therefore, if the blades are set to cut at one depth and the user hits a point that sits higher under one blade than the other, then one blade may penetrate the roof deck while the other cuts the membranes just right.

After the roof is cut in a checker board design, proceed with a powered roof remover. "A powered roof remover easily doubles a workers output," according to Mr. Blue. Manufacturers of powered roof removers claim that this wonder tool does the work of 6 to 8 men and reduces the costs over hand labor by 50% or more. The contractors we have talked with support this claim as well. "Nothing works faster!" said Mr. Blue. The remover comes with two blades. The wide cutting blade is designed specifically to remove roofing from the insulation. The second blade, the tough duty toothed blade is the most frequently used blade on most roof removing jobs. The important thing to remember when using a powered roof remover is to make sure the roof can support its weight. The unit weighs approximately 650 pounds. Definitely not recommended for light duty decks.

A wheeled tearoff bar is the recommended tool for light duty jobs. It is also very handy to use in those hard to reach areas on the larger jobs. The principal behind it is elementary. It has two grip handles to maximize one’s leverage. Simply push the blade under the roofing material and then push down on the handles to pry the roof up. The added leverage these handles provide minimizes the back strain on the user (a draw back when using tear off spades). Wheeled tear off bars generally come with a 10" steel flat blade and offer a 10" shingle blade as an option. The blade is the only thing that ever wears out on this tool and it is replaceable.

Removing nails can also be a very time consuming ordeal. Solid steel nail bars and Midwest nail bars can easily speed this process. Both tools are equipped with long handles to eliminate having to stoop over for long periods of time. They are also perfect for removing shingles, cap sheets and insulation.

Once the roofing debris has been freed from the roof deck, it is time to transport the materials to a predetermined point and off load them from the roof top. A four wheeled trailer with a dump tray makes this process fast and easy. For large commercial jobs, several trailers can be hooked together and towed with an all terrain vehicle. Small jobs requiring only one trailer with dump tray can be hand pulled. Most four wheel trailers are equipped with a brake bar so that they can be used independently of an all terrain vehicle. When the tongue (handle) is dropped, the brake bar makes contact with the front tires and stops the trailer from further movement. Keep in mind, the trailers are recommended for flat roof use only. Wheelbarrows are also another viable alternative for hauling debris on smaller jobs. There are choices to make here also. Two wheeled wheelbarrows offer better stability while a single wheeled model is easier to maneuver. Any cart or wheelbarrow is at risk for flat tires. However, the expense both in replacement costs and down time lost can be eliminated entirely by using a light weight solid tire. They are guaranteed never to go flat.

The final phase in a tear-off job is removing the cumbersome debris from the roof and getting it to the ground. Implementing the use of a trash chute system can be instrumental in reducing the cost and time involved in such an undertaking. Too, these units greatly reduce the danger of uncontrolled falling debris. They are easy to set up and can be used on window/parapet mountings, scaffold mountings and flat roofs. Chutes are constructed of a flexible material for durability and easy storage. To store, just unhook them and lay flat.

Here are our recommendations for a safe set up. Always use cantilevered supports such as 4 X 6 or 4 X 8 wood beams or steel beams. These supports must be anchored to solid construction such as load bearing beams or floor/roof joists. The supports must be capable of suspending the weight of the hopper and the aggregate total of the trash chute plus a 3 to 1 safety factor (a chute weighs approximately 28 lbs. per section). Further secure the chutes by running a cable through the chutes from the cantilever supports to the ground. This will prevent the wind from blowing the chutes around. As an added safety precaution, we strongly recommend anchoring every 10^th chute directly to the building. Either run a cable through a window and attach it to a secure part of the building or tie it off to the fire escape or the roof. If a chute should back up with debris, the added stress of the build-up may put too much strain on the whole system and cause it to collapse. To avoid this potential problem, make sure all debris is cut up small enough so that it won’t jam up in the trash chute system. Keep in mind that trash chutes are intended for the sole purpose of directing debris from the roof to the dump trailer, dumpster, etc. They are recommended on most buildings two stories or higher. A word of caution, there should be absolutely no smoking, no open flame, no welding or cutting or any other ignition source within 20’ of the debris box and trash chute system. Debris and chutes can be combustible.

Single story jobs do not require the use of a full trash chute system. Most contractors will construct a wood slide to transfer the debris to the ground. Built right, it can easily support the weight of the tear-off debris and it won’t rip like tarps (another favorite of contractors). Tarps are not recommended for sliding debris from the roof top to the ground. Tear-off debris with nails and sharp edges can easily tear the tarp and cause the debris to fall through. Needless to say, this is not a very safe alternative.

In short, the plan of attack goes something like this:

1. Remove gravel with a powered broom.
   
2. Cut the entire roof with a powered roof saw.
   
3. Lift the old roof up with a powered roof remover.
   
4. Transport all debris to single point with a four wheel trailer equipped with dump tray.
   
5. Unload the debris from the trailer and send it down a trash chute system to the dump trailer or dumpster.
   
   

This systematic approach to tear-off removal relies heavily on the use of equipment, not manual labor. The computer was once considered a trendy piece of technology that no one really needed. It was just another toy to add to the collection. Yet, over time we have all grown to depend on them to run our businesses, our finances, our games, etc. The principal is the same. Roofing equipment is often thought of as expensive toys that are not really necessary. Tearoff spades, pry bars, axes and many hours of manual labor can do the job just as well. Granted the initial expense is higher than these simple hand tools, just as the computer was once considered very expensive compared to manual bookkeeping ledgers. However, the savings in time and labor expenses are considerably higher in the long run.

Bottom line, time is money. Ask any bookkeeper come year end. The computer has been a god sent and equipment too will prove its indisputable worth. To reiterate Mr. Blues words, "Nothing works faster!"

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