Some Practical Tips for Designing a Driveway or Parking Area?
Design by Dimension
Keep in mind the dimensions of commonly used paving equipment. Most paving machines have a normal placement width of 8 to 12 feet. The machines work best when paving in straight lines and when making square corners. Laying out a driveway with circular shapes and varying widths requires a combination of machine and hand-applied paving materials, which will create the possibility for an uneven surface texture and poor joint match-up.
In addition, the roller compaction of machine versus hand-applied material will not be equal. This could cause noticeable variances in the surface. For a single lane, the best results are achieved with a width between 8 and 12 feet, and a combination of 8 to 10 foot widths for larger areas. This is your best guarantee for a more attractive appearance and tight, longer-lasting pavement joints.
The last procedure performed by the excavator on your job site should be the digging out of the driveway/parking area, and grading in a quality crushed stone base. Your paved driveway needs frost protection to prevent cracking and heaving, just like the basement walls of your home. Therefore, a dry, crushed stone base should be placed beneath the bituminous paving material. The type and size of the crushed stone will vary, depending on soil type, presence of water, natural drainage, etc. How should you proceed?
The best next step is to have your site inspected by an experienced paving contractor before you place the crushed stone, while the excavation equipment is still on site. The excavation of the pavement area should extend the width of the stone base 6″ wider on each side of the roadway, beyond the planned pavement width. This will protect the edges of the pavement during construction. Be sure to keep the finished grade of the stone base 3 to 3 1/2 inches below the desired finish grade of the pavement. Proper base placement will save you money at a later time, and more than likely require only ‘touching up’ by a paving contractor when you are ready for final paving.
The thickness of pavement required for a quality job will vary depending on the depth of the crushed stone base, the strength of the sub-surface and the traffic load. The best way to determine depth is to conduct an on-site inspection and discussion with an experienced contractor. You can work out the best combination for your budget, usage, etc.
Remember, the strength of bituminous concrete increases with the size of the stone used in the mix. For example: a 2 1/2″ application of bituminous base material, overlaid with 1 1/2″ of wearing material, all on top of a base of 4″ to 6″ of crushed stone, will provide 15 to 20 years of maintenance-free service under normal driveway use. Do it right the first time.
Bituminous vs. Portland Cement
Why choose bituminous? Because it is designed for both flexibility and strength, is much easier to repair when damaged, is less expensive to install and, with proper care and maintenance, will last as long as Portland cement.
Placing Portland cement concrete with hand trowels, working along a string line, is completely different than placing bituminous concrete at 300 degrees Fahrenheit, with a mechanical paver and heavy roller. Whenever a flexible material is applied with very large equipment, every square yard of pavement will not always be identical in appearance. Pavement surfaces compress at different rates and may leave some minor roller grooves. If some areas are hand-applied, and others are machine applied, there will be variances in surface texture.
It is important to remember that none of these imperfections have any effect on the life of the pavement, and generally disappear after a few months of use. The same flexibility that prevents bituminous pavement from cracking over the winter months causes difficulty in applying without some surface irregularities. A timely application of driveway sealer will smooth over most imperfections and provide a ‘like new’ appearance to any pavement surface.
Wait at least 1 to 2 years to apply sealer to your new driveway. The paving material needs that time to cure completely. The main function of sealer is to protect the pavement from damage caused by oil or gas leaking from vehicles. These fluids can cause the asphalt to separate from the aggregate, creating potential problems. When sealing your own driveway, it is vital to use only materials that are manufactured from a coal tar base. Look for this information on the container. Beware the ‘drive-up and spray’ people who will attempt to sell you a bill of goods. Not all spray materials are the same and poor quality materials produce poor results. The best contractors will be happy to provide you with multiple references. Your best protection against a low-quality job is choosing the right contractor.
Meckley’s Limestone Products insists on quality specifications, or we won’t do the job. We correct any errors that affect the longevity of the driveway – at our expense. Remember, your greatest guarantee of longtime service is proper installation. We will supply you with PennDot approved materials, application with the most up to date equipment and techniques, and an extremely qualified and experienced workforce. While we cannot promise perfection, we do guara