Asphalt Paving

Architects generally design parking lots to last for 20 – 25 years. A good average is 20 years. Unfortunately, designs on paper and actual conditions in the field can vary quite significantly, and since the parking lots tend to be the last item of a construction project, and is obviously less structurally important than the building itself, corners can be cut leading to significant decreases in the parking lots useful life. Parking lots that were constructed before the 1970’s seem to have held up better over the years than ones constructed in recent years. Although this is a general statement, the phrase “they don’t build them like they used to” seems to be true. For structurally sound pavements that are experiencing isolated failures, a maintenance program of patching, seal coating and striping will prolong the life of the pavement almost indefinitely.

When Chamberlain does a complete rehabilitation project, the design life is usually 20 years plus, unless cost constraints necessitate altering the timeline.

A site inspection is required to assess the remaining useful life of any particular parking lot. Chamberlain’s Pavement Profile is a computer modeled study that can predict with accuracy how much useful life is left in a particular parking lot.

There are many factors that lead to premature asphalt pavement deterioration. In no specific order deterioration factors can include:

1. Original construction quality.
2. Heavy loads placed upon the pavement (a fully loaded tractor-trailer or trash truck exerts as much deteriorating force on a pavement as 10,000 cars).
3. Petroleum spills, since asphalt is an oil based material, any oil based product that is spilled upon it will dissolve the cement that bonds the asphalt together and cause premature failures.
4. Cracks- Asphalt is a flexible pavement and cracks are a natural part of the aging process. Left unfilled, these cracks will allow water penetration into the sub-base which will prematurely cause pot holes and other types of extensive pavement failure.

Chamberlain is a leader in the use of recycled materials. Crushed concrete is state approved as an equal to crushed stone. Foamed Asphalt, or FSB, is also state approved for use as a base material in full-depth asphalt patches and in new pavement construction. We are the only local contractor to have been pushing the use of both materials for over 10 years.

The Americans with Disabilities Act is a federal mandate for handicap parking space requirements at buildings open to the public. This federal legislation was passed in part due to inconsistencies in handicap parking requirements by local jurisdictions. The federal guidelines are as follows:

1. Number of accessible parking spaces required for commercial properties, open to the public

2. Layout
Accessible space – 8′ with 5′ hashout on left side, Two spaces can share a hashout.
Van Accessible – 8′ space with 8′ hashout on right side

3. Signage
Accessible – Regular handicapped sign – Reserved parking and universal logo in center of each sign. Bottom of sign must be between 4′ and 7′ above pavement surface.
Van Accessible – Same as above, except that the words “VAN ACCESSIBLE” shall be printed below the logo.

4. Grade
Spaces, access aisles, loading zones shall have maximum slope at 2% (1:50) in all directions.

The answer depends on the current state of health of your parking lot. If the lot was well constructed and is not showing significant sub-base failures (more than 5% of the lot) then the best option usually is to start a maintenance and seal coating program. This involves filling cracks, cutting out and replacing severely deteriorated areas with full depth asphalt, seal coating with 2 coats of a good cold tar sealer like Amguard, and restriping. This should be done every 3 – 5 years, depending upon how much traffic your lot has. You will find that over time, the amount of patch work (which is the most costly component) will go down.

For parking lots that are not structurally sound, your best bet is to have a complete pavement analysis done. Chamberlain’s Pavement Profile System is the most fool-proof way to get the information necessary. Sometimes the only flaw is that too thin of a layer of asphalt was put over a good sub-base. In this case, patching and overlay is a viable option.

If subsurface water is a problem, then French drains may need to be installed prior to the overlay. There is no “one solution” for repairing all parking lots. Chamberlain estimators look at each lot on its own merits and make recommendations for your particular situation. That’s why its important to deal with a full service company that does all aspects of pavement repair maintenance. Most other companies do not offer the full range of services that Chamberlain does.

Asphalt will last to its maximum potential when compacted to at least 92%. Chamberlain is the only local company that provides free compaction reports on larger jobs.

Some concrete curbs hold paint beautifully, and others are chronic peelers. One extreme or the other, and there seems to be very few properties that are marginally peeling.

Curbs that have yellow paint that habitually peels are showing current symptoms of a problem that was generated when the curbs were first poured. Concrete takes 28 days to reach its full hardness, and can give off dust for another 6 months after that. Therefore the curb must be allowed to fully cure before paint is applied. Even then it is necessary that a thorough brushing or air blowing be done prior to painting. If this is not done, the curbs will peel, and peel again, over time. If you look closely at your peeled paint, it generally peels all the way down to the original concrete. There may be 2 – 10 layers of paint but they all come off at once. Therefore the problem is not with the most recent painting job but with the original one.

One solution is to sand blast or water blast all of the paint off the curb back to original concrete. Then we can repaint the entire curb with an oil base paint which will stand the test of time. This usually corrects the problem.

At Chamberlain, your dedicated project manager will guide you through each step of your project. You will never get “passed off.”