Ask Gary ADA

Posted By Gary Renick on December 19, 2008

Well things are finally back to normal around here. Everything is cleaned up from the storm and we finally were able to tackle our first do it yourself accessibility project. And what better place to start but the front door. Up until this project I had been using a wooden ramp to get in and out of my house. So we decided to put in a concrete ramp to replace the wooden ramp. Let’s start with a few basics about ramp building. A straight short run ramp that rises 30″ or less should be a minimum of 36″ wide. No single run of a ramp can rise more than 30″. If it rises more than 30″ there must be a landing that is a minimum of 36″ long. Ramps with rises of more than 4″ should have a 1″ curb on both sides to prevent a wheelchair from rolling off the sides. Today most power chairs can easily climb over a 3″ curb so I would recommend at least a 4″ curb. Additionally any rise over 12″ should include railings of at least 36″ height. The ratio for the incline of a ramp 1/12 which means for every 1″ of rise you need 12″ of run. So a ramp that rises would be 30’ long, right. Wrong we forgot the landing at the top, so it would be 33’ long. In most residential settings this length would be impossible to deal with, so if you need to deal with a rise of this type it is best to break the rise up into smaller rises and use a switch back style to negotiate this rise. You might use two ramps that rise 15″ each and are 15’ long with a 6’ x 4’ landing in the middle and a 3’ landing at the top. With modern slab construction you rarely deal with a rise of more than 4″ at the most. Even modern homes with a basement don’t rise more than 12″ above grade.

For this project our rise is 4″ at all of the points we want to place ramps. So using our ratio of 1/12 our ramps will be 4’ long. We also will not need a curb on the sides so we decided to slope the sides so we would not have any sudden drop on the sides. First we will need to determine our ramp dimensions. We measure our rise, in this case from the porch to the top of the bricks below the metal threshold. Next measuring from the center of the doorway mark off 18″ in both directions. Next from our 18″ marks we marked off 4’ from the face of the bricks. Using a straightedge we connected all our marks to create the edges of our ramp. Make sure to sweep the area well before you make your final marks on the porch. It is important that the area is free of all loose material and sand so that the concrete bonds well. Next we gather all of our materials and tools. I had originally I had estimated that it would only require two 40 lb. bags of concrete mix per ramp. Actually it required twice that much for each ramp. We also discovered we needed a float as well as a trowel to do the job right. Not shown in the photo is also a hoe. This we found was a very necessary tool when it came time to mix the concrete. You need to mix the concrete somewhat drier than the directions call for. This is because we are not using forms to define the shape of the ramp. At least in the case of two of the ramps we built this was true. The ramp at the back door needed to wrap around a odd angle so we did use a form for that one. So to recap the materials and tools you will need for one 3’ x 4’ ramp with a rise of 4″ are, 4-40 lb. bags of concrete mix, water, a tub to mix in, a hoe to mix with, a trowel, a float, and a tape measure and straight edge. Now it’s time to get to work. First we need to mix the concrete to a stiff mixture. Then starting at the center of the threshold begin piling the concrete up the 4″ height and out to the 18″ marks. Keep piling the mix out from the door gradually sloping do to 0″ high at the 4’ mark. You aren’t trying to make it pretty yet, you just want to get the mix where it needs to be to cover the entire ramp area. Next you will want to shape the sides of the ramp so they slope at about a 30 degree angle on both sides. Now it’s time to refine our shape and smooth the finish of our ramp. Using the trowel we begin to shape the ramp into the final shape we want. We want to be sure we are level from side to side and that we have a smooth approximate 5 degree slope from the threshold to the end of the ramp. Then it is time to “float” the ramps surface. This means bringing a smooth surface to the top by gently tapping the aggregate down below the surface and leaving a watery layer of cement on top which gives us a very smooth surface. Once this is done keep everyone off of the ramp for twenty four hours. Once completed it is very hard to tell that it wasn’t always there.

Categories: Do-it-yourself, Handicap Issues, Residential Standards
Tags: accessibility, accessible, accessible home design, Handicap Issues, powerchair, Remodeling Ada Handicap Compliance, Simple Wheelchair Accessibility Modifications, Wheel Chair Accessible Home, Wheel Chair Accessible House, wheelchair, wheelchair accessible, Wheelchair Accessible Remodeling Ada, Wheelchair Accessible Remodeling Adaptive