What is tar & chip paving?
Tar & chip paving (which is also referred to as chip sealing), is very similar to asphalt, as it is a combination of hot liquid asphalt cement, liquid A/C (or hot tar if you prefer) as a binder and gravel as the main structural component. Unlike asphalt, which is premixed at an asphalt plant, the components are delivered separately and mixed on the jobsite. Tar & chip is nothing new, its has been used for over 100 years, all over the world, with great success, to pave and resurface roads, parking lots, residential driveways, etc. and is used by county and DOT road crews on road paving projects, in virtually every state in America.
How is tar & chip installed?
After the prep work is completed (which is almost identical for tar & chip paving, as it is for asphalt paving)
First a coat of liquid A/C is applied to the existing surface. This is accomplished by using a computer-controlled distributor truck equipped with spray bars, to apply an exact and consistent amount of liquid A/C, heated to the right temperature.
Then a clean, crushed chip stone is spread using a spreader box attached to the dump truck transporting the gravel. The stone adheres to the hot liquid asphalt
finally; a roller is used to imbed the stone into the tar. The entire process is repeated on jobs where multiple courses are required.
How long does tar &chip last?
This is a very difficult question to answer, because it depends on two factors.
Perspective: To some people, a paving job would need to be re – done as soon as it gets a worn spot or broken edge, while others will be perfectly content dodging potholes for many years as long as they have a clean paved surface for vehicle traffic.
Job site/usage: Durability can vary based on several factors such as climate, traffic conditions, base, and the number of courses of chip seal used, naturally asphalt or tar & chip will last much longer on a low traffic, residential driveway than they will on a county road or city street.
Answer: Let’s say we are talking in averages. Let’s assume that we are talking about the point where a paved surface is in bad enough condition that repairs are no longer a viable option. And that job site, traffic conditions are pretty typical. The life expectancy for an asphalt paving job is probably around 12 years and in that time repairs such as patchwork, crack sealing and seal coating will be required. For tar & chip, probably around 8 years and in that time repairs such as patching and isolated re – tar and chipping will be required. Tar & chip paving, should last approximately two thirds as long as asphalt paving would on the same job.
Why use tar & chip, instead of asphalt?
Tar & chip, provides a beautiful rustic alternative to asphalt, with the look and feel of a country gravel road.
Very cost effective:
The initial cost of installing tar & chip, can be up to 40% less than a comparable asphalt installation.
Unlike asphalt which requires seal coating every few years, tar & chip, is virtually maintenance free, as there is never a need to sealcoat.
The rough, gritty, surface of tar & chip, gives great traction even in wet weather, and is an excellent choice for steep slopes.
Because of its light colored stone surface, chip seal does not absorb heat like blacktop does, and stays much cooler.
Tar & chip, goes down faster than asphalt and there is hardly any down time, because it can be driven on immediately; you do not need to wait 24 – 48 hours for it to harden.