How is a Tar and Chip Driveway made?

Tar and chip driveways are very similar to blacktop or standard asphalt driveways. Both are usually installed on a compacted gravel base. The base is the foundation or strongest part of the driveway. Blacktop and/or tar and chip surfaces are actually flexible. They are the actual wear layer and prevent the erosion of the gravel base.

How is tar and chip different from blacktop?

A tar and chip driveway differs from a standard blacktop driveway in that it is made on site. The hot liquid asphalt and stone chips are actually applied simultaneously on the gravel base.

Blacktop, a mixture of asphalt, sand, and gravel,on the other hand, is usually mixed at an off site plant. It is delivered, much like ready mixed concrete, to your house and applied with a special spreader. If you are installing a brand new or reconstructed driveway, you will do well to have two layers of tar and chip done. That gives a nice thick coating and a surface that may last up to 12 to 15 years. If you have an existing blacktop driveway, you may get by with a one coat application.

Get the best-looking Tar and Chip Driveway around! Use my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist and learn what to ask your contractor. I offer a 100% Money Back Guarantee.

Advantages of Tar and Chip

Standard blacktop pavements require protection from the sun and air. The asphalt that bonds the sand and gravel together can become brittle. If you have a blacktop driveway you have probably had to seal it with a liquid coating. Tar and chip driveways do not require this periodic maintenance.

Tar and chip driveways are slightly rougher than a standard blacktop driveway. This characteristic comes from the fact that small, cubical shaped stone chips are dropped directly into the liquid asphalt. The surface, after it is compacted with a heavy roller, resembles a chunky chocolate chip or oatmeal cookie. The surface isn't smooth, yet it isn't sharp and abrasive. It is in between. This surface provides excellent traction in wet or snowy weather.

What Makes up the Paving Surface

Asphalt - Two Types

The liquid asphalt that is used to coat the driveway and act as the adhesive for the chips can come two ways. It can be a cutback asphalt which is specifically formulated for your region. These asphalts are sticky and release hydrocarbons into the air as they cure. Their use is sometimes curtailed when ozone production poses a smog problem.

An alternative asphalt is an emulsified mixture. This is similar to many blacktop sealers you buy in a 5 gallon pail. The asphalt is atomized into small tiny drops and coated with an emulsifying agent. Sometimes these emulsifiers are water based. As the water evaporates the asphalt is released so it can bond to the surface and to the stone chips. If you can arrange to have the old fashioned cutback asphalt, use it. That is what I used on my own driveway.

Loose Chips

If your driveway is fairly level you may wish to top the driveway with a layer of loose chips. It is extremely attractive. The look is just like that of a country lane or a roadway in a park. A 1/2 to 3/4 inch layer is all you need. The loose chips protect the asphalt from the damaging effects of the sun. In addition, should a crack develop in the driveway, the loose chips fill and disguise the imperfection.

Loose chips, however are not appreciated by young bicycle riders and basketball players. If these people live with you, you may wish to create a concrete or standard blacktop surface in these areas. Then extend the tar and chip surface from the play area to the street.

Who Does This Type of Work?

Tar and chip pavement surfaces are nothing new. In fact, there is a strong possibility that you have driven across hundreds of these roads. Many counties use this surface on secondary and rural roads. It is a cost efficient method of repaving and sealing an asphalt roadway.

Businesses and manufacturing plants often pave large parking areas with this material as well.

There is a good chance that a large paving contractor in your city or town does this work. If you are really fortunate, you may find a smaller company that does it as well.

If you have trouble locating a contractor in your town, there is one sure fire way to determine if this paving system is done in your area. If there are blacktop or asphalt driveways in your area, there is an asphalt plant. This is where blacktop is made. This is the same place where the tar and chip people must purchase the tar or asphalt cement. Find out where the plant is and call and speak to the general manager. Ask if he can put you in touch with the contractors who purchase the tar.

Column B127

There are two national organizations that deal with asphalt information and technology. Both have excellent web sites, although much of the material is somewhat technical. The two organizations are:

• National Asphalt Pavement Association
  www.asphaltpavement.org/

• Asphalt Institute
  www.asphaltinstitute.org

The Asphalt Institute has a publication in particular that deal with tar and chip surfaces. Although it is technical in nature, it provides you with a good background of what the surface is, how it is made, the equipment used to install, etc. In other words, if you want to make sure your tar and chip driveway is going to be installed correctly, it may be worthwhile reading!

Get the best-looking Tar and Chip Driveway around! Use my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist and learn what to ask your contractor. I offer a 100% Money Back Guarantee.

The best publication is ES-12 Asphalt Surface Treatments - Construction Techniques. This one has it all. It is a must read. It costs $15.00.

Column B127

Weather & Tar and Chip Driveways

Weather conditions are very important when it comes to these surfaces and their installation. Hot, dry early summer weather almost always offers the best conditions. The liquid asphalt sticks best to warm dry surfaces. It also sticks to falling leaves and flower petals! This means that you don't want these things around when you are installing a tar and chip surface.

CLICK or TAP HERE for a FULL TRANSCRIPT of the above video.

Air and surface temperature are critical. It is important that once the hot liquid asphalt is sprayed that it does not chill or cool before the loose chips are scattered across the asphalt. In fact, in most applications, the chips are usually installed within 1 to 2 minutes. The faster the chips are installed, the better chance they have of sticking to the liquid asphalt cement.

If you have to use an emulsified asphalt, be careful of rain. If it rains before the emulsifying agent evaporates, your asphalt can wash away!

Leaves, Grass & Snow

If you have an obsessive compulsive behavioral disorder, tar and chip may not be for you! If you choose tar and chip and the beautiful loose chip covering, you will not be able to hose down your driveway. You'll blast away the chips! However, grass clippings, fallen leaves and paper can be easily removed with a standard air blower or a lawn mower. That is how I remove these items from my driveway.

Get the best-looking Tar and Chip Driveway around! Use my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist and learn what to ask your contractor. I offer a 100% Money Back Guarantee.

Snow removal is also a challenge. Hand shoveling is tough. You need to skim just above the chips. However, plowing is possible if you just set the blade up one inch. If you have no loose stones on your tar and chip surface, plowing is no different than a blacktop or concrete driveway.

Cost

The cost of a tar and chip driveway is almost always less expensive than standard blacktop. The cost rises if you choose an expensive colored stone. Maintenance is virtually non-existent. Remember, you don't have to deal with those messy sealers every other year. That saves time and money as well.

Do's and Don'ts of Tar and Chip Driveways

Do's . . .

Do use a contractor who has experience with this surface. Ask for references and go and visit the driveways.

With proper installation, your home tar and chip driveway can stand up to the weight of a fire engine. PHOTO CREDIT: Tim Carter

Do make sure that the contractor plans to spray a sufficient amount of liquid asphalt. One half gallon per square yard is the minimum amount that should be applied. Applying too much can also be a problem. The tar may bleed through the chips in hot weather!

Do make sure that the base or surface to be coated is sufficiently strong enough to handle the heaviest trucks! The tar and chip coating is NOT structural. It is merely a wear layer.

Do make sure that the chips you use are uniform in size as much as possible. Flat, thin chips are not too good. Cubical chips, similar in shape to rock salt are superb.

Do a good job of blending stone chips if you decide to use two different colors.

Click here to watch a video on Tar and Chip Driveways.

Don'ts . . .

Don't consider using loose chips if your driveway is steep. The loose chips may cause tires to spin. Steep drives can only be coated with embedded chips.

Don't drive on a new tar and chip surface for a minimum of 24 hours. The surface is tender, just like fresh blacktop. Avoid spinning tires or turning wheels in place for at least two weeks.

Don't allow a cutback asphalt to be applied to a damp or wet blacktop or gravel base. These surfaces MUST be dry! Emulsified asphalts can be applied to a damp surface.

Don't apply an emulsified asphalt if rain is in the forecast.

Don't apply asphalt if the air temperature is less than 50 degrees F. The temperature should be rising though the process. The surface temperature of the gravel or blacktop to be coated should be at least 70 degrees F.

Column B127

Tips on Patching Blacktop and Asphalt

©2017 Tim Carter

Square Edges: The sides of the hole to be patched must be vertical. Don't expect to pour cold patch materials in a depression or sunken area of blacktop and expect it to last. The crisp vertical faces of a hole act as retaining walls for the patching products.

Remove Loose Debris: Once you have created clean edges on the hole, remove loose debris from the bottom of the pothole. If the pothole is deeper than 2 inches, then use this coarse blacktop and other crushed stone as fill.

Compact Base: Use a steel tamping plate, a 4x4 or other tools to really compact the stone base. Avoid using rounded gravel as a base. Always use crushed, angular stone.

Correct Thickness: The ideal depth of asphalt patching material is between 1.5 and 2 inches. If you install it greater than 2 inches in depth, it can take much longer for the high performance adhesives to fully cure!

Compact Patch - Do NOT Seal!: After the patching material is in place and about 3/8 of an inch above the surrounding pavement, use a steel tamper to firmly compact the cold patch material. Check it for low spots with a straight edge. Do not under any circumstances cover the patch with asphalt sealer. Wait a minimum of 30 days. The patch needs to be exposed to the air so it can cure.

Do you need to patch your asphalt? Save time and money by using my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist. I offer a 100% Money Back Guarantee.

Crack and Edge Sealers: Once the patch has cured, you can use a high performance crack filler to seal the edge between the old blacktop and the new patch. Use a 1/2 inch wide disposable paint brush to spread the crack filler so it bridges the crack evenly.

Filling Cracks: Most crack fillers will settle slightly as the water in them evaporates. You can fill a crack level and let it dry and then refill, or you can experiment and see if you can carefully overfill the crack leaving a slight hump to see if the material dries level. Deep cracks may need to be filled with coarse, dry sand before you add the liquid crack filler!

Companion Articles:   High Performance Asphalt Repair Products, Asphalt (Blacktop) Patching Material, Asphalt Patching

Column B283

High Performance Asphalt Patching Products

If you want some really good products to patch your blacktop driveways, you need not go too far. If you are lucky, you might have an old fashioned building supply store near you. This is a place that commonly sells, brick, mortar, cement, reinforcing steel, drainage pipe, and similar building products, etc. We have at least 3 or 4 of these still left in my hometown.

Often these places sell cold patch blacktop. Years ago, the cold patch products were just formulated to act as a temporary patch until a contractor could come along and install hot mix asphalt. Well, as with many things, improvements in adhesives and glues have found their way into cold patch asphalt. If you can find one of the products listed below, you can install a permanent blacktop patch if you follow the instructions on the bag. I have done it numerous times and many of the patches look as good as new.

The building supply stores will also sell blacktop or asphalt crack sealing compounds. These products are often an emulsion of asphalt and synthetic rubbers. The more rubber that is in the mix, the better the crack filler will perform. As you might expect, products with more rubber cost more. Look for the most expensive crack filler and purchase it. Follow directions to the letter. Most require that the crack edges are clean and dry. This means you will often have to wash them out with a hose on one day and then fill them the next day after the cracks have dried out.

Call the manufacturers below to find out where in your area you can find them. They might be available at a large home center, but don't count on it!

Do you need to patch your asphalt? Save time and money by using my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist. I offer a 100% Money Back Guarantee.

• EZ Street
  EZ Street Company
  1786 NW 82nd Ave.
  Miami, FL 33126
  800-734-1476

• High Performance Cold Patch
  Hy Grade Corp.
  3993 E. 93rd Street
  Cleveland, OH 44105
  800-341-7751

• PLM 1010 High Performance Cold Mix
  PLM Corporation
  7424 Bessemer Ave.
  Cleveland, OH 44127
  216-771-8555

• QPR - 2000
  QPR, Div. Lafarge North America, Inc
  12735 Morris Road Extension
  Alpharetta, GA 30004
  800-388-4388

Companion Articles:   Tips on Patching Blacktop and Asphalt, Asphalt (Blacktop) Patching Material, Asphalt Patching

Column B283

©2017 Tim Carter

Black Rubber

Several years ago, the highway maintenance crew in my village worked on my street. The first thing they did was to use compressed air to blow out debris from the cracks in the roadway and along the curb. Several hours later, a large dump truck arrived with a strange trailer. The trailer contained a tank filled with a high performance crack filler. This tank was heated by a propane burner. The material in the tank was an asphalt solution that contained some new synthetic rubbers. The maintenance person who walked with the trailer had a wand that was suspended from a boom. As he squeezed a trigger, hot material would flow from the wand tip. A second person had a V shaped squeegee that pushed the material down into the crack and it also spread it onto each side of the crack.

The material has done a fine job of filling the cracks. You can get very similar materials that do not require heating. The best crack fillers have lots of rubber in the mixture and typically cost twice as much per gallon as the inferior or low- tech crack fillers.

The crack fillers pour right from a bottle or jug. I have determined that the trick to getting them to stick is to make sure that the cracks are clean, dust free, and dry. If you have the patience to make this happen, you can get long term crack repairs.

Do you need to patch your asphalt? Save time and money by using my Asphalt/Blacktop/Tar & Chip Installation & Repair Checklist. I offer a 100% Money Back Guarantee.

Patching Potholes

I have seen many a friend and relative fail miserably at trying to patch low spots or depressions in their blacktop driveways. In the past they could blame their failure on the material they were using. They can't do that any longer.

You can now purchase pothole patching compounds that are in a bag and will produce permanent repairs if you follow several easy steps. It is important to buy the right materials. I list several high performance products later in this bulletin. Do your best to find one of these great products if you want to only patch your potholes once.

Oh yes, the other reason that pothole repairs fail is because the material was not installed right. I'll bet you have seen holes or low spots develop in your driveway where the actual asphalt simply sinks. You can't see down to the gravel base as the asphalt stretched over the hollow spot.

To repair holes like this by simply dumping in some cold patch is asking for trouble. As the cold patch material nears the edge of the depression, it thins out to nothing. To repair a depression like this you must crack the surface of the asphalt and create vertical edges in the existing blacktop that are at least 1.5 inches high. You can see that when the patching material is installed this way, its minimum thickness at any point would be 1.5 inches, not the thickness of a solitary asphalt coated stone from the patching mix!

In a Rush

Are you an impatient weekend warrior who has decided to fix the driveway holes, cracks, and seal it in one weekend? Well, forget about it! If you have to do all of these things to a driveway, it is going to take a minimum of four weekends. You should patch the holes on the first weekend. As soon as you expose the patching material to the air, you begin the 30 day countdown that is required to allow the material to fully cure and get hard. If you cover the patch with driveway sealer, you block air from getting to the patch. The patch will then be spongy for a long period of time. Spend the second weekend cleaning cracks and getting them to dry. Apply the crack filler and let it set for one week. Check to see if you need to fill deep cracks twice. After 30 days, apply your sealer!

Companion Articles:   Tips on Patching Blacktop and Asphalt, High Performance Asphalt Repair Products, Asphalt Patching

Column B283