Wood wheelchair ramp.

Wheelchair ramps can be made of many materials, including wood. While wood is relatively inexpensive at the outset, it can be more expensive later due to maintenance costs.

iStockphoto.com/Phil Cardamone

­Twenty years ago, wheelchair ramps weren't the common structure they are today. It wasn't until the Americans with Disabilities Act (ADA) of 1990 that there were any sort of guidelines dictating the need for ramps and other aides to the disabled.

The ADA is a federal civil rights law that prohibits discrimination again people with disabilities in everyday activities [source: United State Department of Justice]. Now, some public buildings are required to have ramps that make their building more accessible to ­those with disabilities. If you're thinking about adding a ramp to an existing structure, it may be a project you can take on yourself, but the responsib­ility shouldn't be taken lightly.

Wheelchair ramps, when constructed correctly, are safe, sturdy structures that allow disabled people access to places they might otherwise not be able to go.

The ADA made everyone more aware of the obstacles blocking disabled individuals from doing things they wanted and needed to do. The ADA has created a set of guidelines that standardizes the wheelchair ramp building process and specifies the materials that should be used, making ramps safe for everyone. There have been many lawsuits over wheelchair ramps that created a hazard, and most hazards are a result of neglect.

­In this article, you'll learn about ADA wheelchair ramp specifications, slope ratio and ­horizontal projections. You'll also learn about width, handrails and guardrails, and how best to protect ramp users. We'll also go over the different materials that can be used for building wheelchair ramps, as well as the pros and cons of each.

You'll also learn the basic steps used to install a wheelchair ramp, as well as some things you need to look out for before your ramp is ready for use. There are many wheelchair ramp options. You can build or purchase a ramp -- whatever is best for your specific needs.