Porous Asphalt

Today, porous asphalt is undoubtedly one of the most popular options for public-works departments and site planners. With proper planning and installation, it can provide attractive and cost-effective pavements with a lifespan of more than 20 years. More importantly, porous asphalt roads are also easy to infiltrate, improve the quality of water, and eliminate the needs for a detention basin. In this post, we’ll show you a step-by-step guide to install a porous asphalt pavement.

1. Demolition & Removal

Firstly, the existing surface should be removed, whether it’s pavers, concrete, or asphalt. This can be done by using a heavy machinery like a forklift, bobcat, front loader, or dump truck.

2. Sloping and grading

Once the surface has been cleaned, it’s time to prepare for proper water drainage. With automatic graders and laser-guided, the workers will pave the surface to make sure that water can run off appropriately. This is important as water is a leading cause of damage to porous asphalt, including heaving, cracks, and potholes.

3. Preparing the sub base

This is the most important step of installing porous asphalt as it will provide a stable base to support the pavement. Also, it works as a frost barrier to reduce damage due to thawing and freezing in winter. If the sub-base isn’t compacted correctly, the top surface won’t last long.

4. Proof roll

Once the sub base’s fully compacted and graded, it’s time to drive a dump truck to row over the whole surface. This to ensure that the underlying layer is strong enough to support a new layer of porous asphalt.

5. Adding binder

The next step is to install the binder, which is a layer of large aggregate combined with oil to make it durable and strong. In other words, it can be considered as the strength of the porous asphalt surface.

6. Installing new porous asphalt surface

Once you’ve installed all supportive structures for the porous asphalt surface, it’s time to add the top layer of asphalt to provide a smooth and clean ride. In general, this layer is made of oil, sand, and small aggregate.

7. Butt transitions and joints

As it is not common to install a porous asphalt surface which doesn’t connect to an existing driveway, roadway or parking lot, it is necessary to smooth the transitions from old to new surfaces. This step is known as butt joints. Once the joints have been laid, now we have a smooth and compact surface.