Image Credit: Mary T. Clark
More Musings of an Energy Nerd
Green builders have an uneasy relationship with chainsaws and bulldozers. To some environmentalists, these noisy inventions conjure up images of ecosystem destruction and irresponsible land development.
However, just like a hammer or a level, a bulldozer is just a tool. It can be used for good or ill.
Bulldozers are extremely handy when you need to change the grade of a site. Grading matters, and novice builders who ignore grading will eventually be forced to pay attention to the topic.
Hippies don’t do grading
How do hippies build a house? They look for a natural clearing in the woods, they put a few piers in the ground, and they build a house on top of the piers. (Although this sounds like a caricature of the hippie approach, it’s fairly true-to-life. I should point out that as an ex-hippie, I’m allowed to make hippie jokes.)
It doesn’t take long to realize the many disadvantages of leaving a natural grade around a building:
- In many areas of the country, the natural grade is lumpy — characterized by protruding stones and woodchuck holes — and therefore hard to mow or maintain.
- During a heavy rain, the natural grade may direct surface water toward your foundation.
- There’s nowhere to play croquet.
Although I have had plenty of experience hiring equipment operators and directing the work of backhoes and bulldozers, my own experiences with grading have humble roots. I have spent many years grading with a shovel, rake, and wheelbarrow. Using these simple tools, I have changed a steeply sloping hillside behind my house into a flat yard that is big enough for my sons and me to practice passing a football.
The shovel-rake-wheelbarrow triad limits how far one can go to obtain material to use for fill. It’s possible to make…
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17 Comments
Serenity prayer invoked
If a writer as good as Martin does it - 'big enough for my sons and I to practice passing a football' - the battle has been lost. Let it go, James. Let it go.
Otherwise, good article. Down my way the seventies and early eighties were the worst, as the hippies gradually went legit with real foundations but the 'save that tree, man' attitude lingered on. You might mention that to do proper grading you have to take out any trees within or even close to the affected area, or the chances are you will watch them die. Except of course for the sweet gums, those cockroaches of the vegetative world. They survive almost anything.
One other thing I'd add - in my experience few soil embankments are stable at a 45° slope without at least some rough rock retainage or other assistance. Unless it doesn't ever rain around your parts, try 30°.
Response to James Morgan
James,
Sorry to disturb your morning with my error of grammar. I've made the correction, and I appreciate your sharp eye.
Was that what got James' blood pressure up?
I thought he was pointing to the grammatical error of your use of "my sons and I" rather than "my sons and me." At least, I think "me" is correct in this case.
Response to Jonathan Teller-Elsberg
I think you're right, Jonathan. James's invocation of the Serenity Prayer had me confused. I assumed he was referring to my grading decisions.
re
I'm just surprised no one else said 'ex hippie!'
A haircut does not make one a yuppie................
But he didn't exactly make yuppie pretentions...
...did he?
There's a real spectrum of ex-hippie-dom out there, but very few ex hippies don the "yuppie" mantle.
ya all need some time
ya all need some time offline..... fun ta read the yap agin though fir a bit...
;)
learnt something new today ... such a creature as a ... god fearin hippie?
site specific
I think that any guilt that may be associated with grading is relative/proportional to the nature of the site, pre-disturbance. If building on a rural, wooded, or steeply sloping site, grading is less desirable... beyond the necessary extents of creating a livable environment. But in urban and sub-urban sites, grading can be an art/craft that has the potential to restore and enhance existing topographies and create desirable new terrain and open spaces. Bottom line, it's all relative to the site. We can't all build on relatively undisturbed, sub-rural 1-acre+ plots and expect that sustainable development is being achieved in doing so. And higher densities generally warrant more grade disturbance.
Earth Work
I understand that uneasy relationship well, having done excavating contracting, and have also had disdain for what bulldozers have sometimes done to the natural spaces I have admired. I have also done a lot of hand excavating with a shovel and wheel barrow. I once calculated that I had moved the equivalent of 18 tandem dump loads by hand on my 60’ X 250’ lot over a period of years. And that was quite a while back before I even started my pond project and drain tile lines. I enjoy the hand work, but the trick is to approach it as Zen. You can’t be focused on getting the job done, because the task will break you. You have to work it day by day. It can be enormously satisfying to stand back at the end of a day and admire what you have created. It is a form of artistic sculpture.
Martin is right about a good equipment operator being one who makes fluid movements with elegance. A good operator has great respect for the machine. A bad operator is easy to spot for his lack of respect for the machine. A bad operator treats the machine like a bull that must be conquered and dominated. He beats the machine to prove he is the master. Heavy equipment might seem indestructible, but ironically, the heavier it is, the more delicate it is. And disrespecting that will be very costly, either as accumulated wear or an abrupt breakage.
A novice perceives a track dozer as being unstoppable and able to go anywhere in the roughest terrain. An expert has the wisdom to avoid every obstacle possible. If a careless turn crowds a track up against a vertical bank, it can break a track or rolling element. It can do thousands of dollars’ worth of damage in a second.
Not only should residential grading be accurately executed, it should also be carefully designed. Grading needs a plan just like everything else that gets built. Sometimes the design can be done just by eye as the work progresses, but it is generally quite difficult to “see” new surface features of grading while looking at the existing terrain.
Therefore, the more complex work will benefit from an actual plan showing the before and after configurations. Using a transit, you measure the relative elevations in a pattern of locations all over the site, and then plot the pattern of those elevations to scale in a plan view on paper. Then you draw contour lines connecting points of identical elevation. That is the contour map of existing site before grading.
Then working with that existing contour, a new proposed contour is developed. Proper drainage is king of objectives, as Martin suggests. It is amazing how many houses are built with insufficient downslope away from the foundation or worse. For larger projects, the existing and proposed contour plans can be overlaid, which will show the volumes of cuts and fills. That way you can see if they balance or if material must be imported if the fills are short. Often, adjustments can be made to help achieve the balance. Excess material can often be used for berms.
I like the idea of built landscapes, but not the concept of large, featureless expanses of turf. Berms, ponds, walkways, retaining walls, rain gardens, trees, and other plantings can add a lot of excitement. Fencing can add intimacy and make it seem like an extension of the living space. Oddly enough, a privacy fence can make the enclosed space seem larger.
AJ's back
Haven't seen AJ in awhile.
Just curious
What specifically is a "bulldozer"?
Out here, the type of machine in Martin's photo is called an excavator, and the particular machine in the photo is a mini excavator. An excavator has tracks, an articulated boom, a set of buckets, hopefully a thumb, and usually a front blade. You can attach a hydraulic hammer, a grapple, a compactor, and other fun stuff. It's the main thing you need for earth work. The customer we're working for right now calls these "steam shovels" and I have not felt like making the correction.
A bulldozer has tracks, a front blade, and little else, and is used for spreading material.
Response to David Meiland
David,
I agree. This article is about grading, and many tools are used for grading. These tools include shovels, rakes, bulldozers, and excavators. All of the listed tools are mentioned in the article, and the photo caption never claimed that the equipment in the photo is a bulldozer.
Martin
I'm not trying to point out a flaw, just genuinely curious if the machine I call an excavator would be called a bulldozer elsewhere.
strange picture
@David Mailand:
A bulldozer is a certified tool, fully insured with a roll bar.
Professional builders wear hard hats, fully insured - under the roll bar...
..............................................
There are data/picture banks for professionals, Martin. For very little money.
Response to Hein Bloed
Hein,
Once again, for perhaps the third time, you have reminded GBA readers that workers in Germany wear cleaner clothes and better protective equipment than U.S. workers, and that U.S. workers (by comparison to workers in German) are "cowboys."
It must feel good to live in Germany.
Terminology
The news media frequently get the terms mixed up and call backhoes, and wheel loaders “bulldozers.”
The term “bulldozer” does not apply to the machine in the photo. That is an excavator, track hoe, backhoe, or mini-excavator. The term mini only applies to excavators in that small size class. Backhoe is the oldest term of that group, and it was used for earlier hoes that predate the modern hydraulic track mounted hoe. Earlier hoes were the tractor-mounted-backhoes that looked similar to a farm tractor, but with a hydraulic backhoe on the back and a hydraulic loader on the front. They are still commonly used. Nobody in the industry would refer to an excavator as a “bulldozer” or vice versa. However bulldozers are used for excavating.
There was also a genre of larger cable operated, steel-track mounted backhoes that were often used in deep trenching for storm sewer lines. I believe the term “excavator” referring to a backhoe is relatively new, emerging with the advent of the hydraulic backhoe on tracks. The term “steam shovel” was left over from the early dipper shovels that were driven by steam. The term was often used by people outside of the industry to refer to the later gas or diesel dipper shovels as well as drag lines. The commonality was that they all had tall booms.
Bulldozers are sometimes called “dozers.” They are on tracks, and originally were only on steel tracks. Today, they can also be on rubber tracks, especially in the small size or “mini” range. So there can be the differentiation of “rubber-track dozer” or “steel-track dozer.” Usually dozers have a blade on the front. Some blades can angle to cast material to one side or the other in a pass, and also tilt up and down, side to side which is convenient for cutting into sloped ground like building a road along a hillside. Those blades are called power-angle-tilt (PAT) blades. Many bulldozers can also be fitted with a hydraulic ripper or a winch on the back. They can also be used as agricultural tractors, without a blade or ripper, just for pulling field equipment.
Bulldozers were invented for this agricultural application where fields lacked ground support. So the objective of tracks was to provide floatation. The original term for them was “tracklayer.” Their tracks with flanged rollers were analogous to railroad tracks with flanged wheels running on them. But unlike a railroad, tracklayers laid their track down ahead of them, and picked it up behind them as they traveled. The steel track chains of bulldozers are still called “rails” as an alternate term for track “chain.”
There is also a class of bulldozer-related machines which are basically steel-track dozers with a hydraulic loader instead of a blade. Those are called “track loaders” or “traxcavators.” They are not called bulldozers or dozers, although they can perform the function of dozing material like a bulldozer. Traxcavators used to be the preferred machine for digging basements, but that role has been largely taken over by the backhoe or excavator class. Nevertheless, traxcavators are still used for a variety of tasks. Unlike a bulldozer, they can load trucks. And unlike an excavator, they can transport material in the bucket rather effectively, and also grade material. Traxcavators can also have a ripper on the back. In a fundamental way, they differ from bulldozers because they have a rigid track suspension, whereas dozers have oscillating tracks with a spring suspension.
Ron
Good explanation. Around here a backhoe would only refer to a farm-type tractor with bucket on the front and a hoe on the back, where the big wheels are. You have to turn the seat around to use the hoe, and moving the machine while using the hoe is a bit tedious, although I know operators who can do it with a hand behind their back, literally.
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