Asphalt Paving Quality Issues

Grading

• Most people spend time driving every day, but not many have ever designed a road. That's what your driveway is: a very simple, short road. One of the most important functional and safety features of any road is how it's graded. Precipitation must run off the asphalt in a sensible way. It can't pool anywhere, unless there's a drain, and it shouldn't drain towards your home. The contour of the soil beneath the driveway has to be graded so the finished drive will drain properly.

Compaction

• Poorly compacted or inconsistently compacted soil can be disastrous. Before asphalt is laid, the underlying soil must be compacted. Otherwise, as cars exert weight on it and as it becomes saturated with water, then dries, again and again, it will compress by itself. The asphalt above it will sag. When it sags, their may be drainage problems. Improper compaction can be the beginning of a very expensive chain reaction.

Prep and Design

• Resist the temptation to asphalt over an existing driveway. You want to start with a new, well-graded, stable soil platform. But, the way you prep and design one job isn't identical to others for the same reasons foundation work isn't always identical. Soils vary from area to area. Some soil may need several inches of compressed aggregate as a base coat. Some may need a light coat of aggregate and a tack coat, prior to paving. The preparation and design has to match the location and conditions.

Heat and Installation

• As with other forms of building, there are no shortcuts. Your job has to be prepared, designed and installed right, the first time. Trying to cut corners like leaving root systems or other plant-life under the soil, invites problems. Skimping on a base coat of aggregate in unstable soil, invites problems. One of the most common problems is heat. Asphalt is very hot when it goes down and, unlike concrete, cannot be installed in a wide range of weather and temperature. Installation is a warm weather activity.