I’m a licensed residential construction contractor in central Iowa. A long-time client left a voice message for me earlier today, asking if I would build a wheelchair access ramp from the ground to an exterior deck at his mother-in-law’s home.
I’ve been in the business for nearly 10 years, but this will be the first wheelchair access ramp I’ve constructed. I consulted my reference material, but struck out. Decided my best chance at building a safe, useful ramp would be to solicit input from my fellow Breaktime readers.
I plan to construct the ramp with pressure-treated lumber. I’d appreciate hearing your suggestions for width, slope, and features you included in your structures. Thanks in advance for your input!
Replies
Google for"ADA guidelines"
Someone here will probably have a link. I'm pretty sure the slope is 1/12 but don't have that confirmed - dang this feeble old memory...
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Here is the link: http://www.usdoj.gov/crt/ada/stdspdf.htm It's about 100 pages of info. It will provide all the necessary specs that the ramp should conform to. Piffin is correct on the 1/12 slope. But keep in mind that is the maximum slope, nothing steeper."Don't take life too seriously, you are not getting out of it alive"
Try for 1:15 slope...it will be much easier to use. 32" minimum width and will work if space is a problem. 42" feels much more comfortable for the users (less claustrophobic). Be careful on turns and switchbacks...be sure to leave enou8gh room to turn if there is any possibility of having the riders legs straight out in front. Toe boards. Handrail low enough for the rider to use, and a comfortable shape...no splinters or exposed fasteners in the handrails!
Gary,
R&R is correct about 1:12 slope as being the steepest grade acceptable. Usually, for outdoor ramps, a slope of 1 inch rise per 20 inches of run (1:20) is what you should strive for.
The Metropolitan Center For Independent Living in St. Paul MN ( phone # 612-646-8342) published a booklet back in 1991 which contains 63 pages of information, including site plans, construction methods, and a detailed cutting list on how to construct ramps using treated lumber.
Basically the ramps are built in 55 inch lengths, using 2X6s for the joists/rim joists. The joists are spaced 14 inch OC. The decking is 5/4X6 which is screwed down using 2-1/2 inch deck screws. This joist structure is supported at each end by a pair of 4x4 posts. These posts are connected by a horizontal 2X6 attached on both face sides of the 4x4 to form a beam. The joist structure sits on top of these 2x6 beams. The horizontal beams are further supported by nailing "drop-legs" or "kickers" underneath each corner, to the 4x4 post. Also, ramps wider than 36 inches should have either plywood gussets nailed on as well, or use 2X4 diagonal bracing, to keep the posts from racking.
Two ramp sections share one set of a "typical" 4X4 support structure. The ramps are bolted to each other at these 4x4 support locations and then the outside joists of each ramp section are lag bolted into the 4X4s as well. (It's best not to install any 5/4 decking until the joist ( ramp) sections are first all bolted in place atop the 4x4 support structures.)
Please note that the 4X4s extend up past the actual deck ramp. The extra post height comes into play when installing handrails/guardrails.
The guardrail system is basically a 2x2 vertical baluster attached to 2x4 or 2x6 horizontal stringers; typical of many decks. If the person using the ramp uses crutches, then a toe-kick board is also reccommended.
This is a pretty straight-forward type of system. If you think the ramp may be more of a temporary nature whereby the ramp may not be needed several years from now and/or the owners may want to move to a new location and want the ramp to be disaassembled and re-located....then instead of embedding the 4X4s into the ground, install 3/4 treated plywood blocking (12 inch square pads) to the bottom of each post.
LOL.
Davo
Why would the joist spacing be 14" ? That seems like an odd number.
The plans he is referring to are designed to be modular, with each section 55" in length. 56/ 4 is 14" Close enough.
I've built them in 6 foot sections with four 2x6 joists about 13" on center for a 40 inch wide ramp using 5/4x6 deck boards. The first one I built at 36" wide (which I understand to be the minimum ADA, not 32"}, but it really seemed a bit cramped. I settled on 40 inch so I could get three deck boards evenly out of a ten foot board. It's amazing how much difference four more inches makes.
Everyone is right about the slope. 1:12 is the ADA minimum, but a gentler slope is better. The problem is that usually getting the 1:12 slope is hard enough.
The toe board is ADA and necessary for wheelchairs as well as crutches. Outdoors it is a good idea to leave a couple of inches under the toe board for snow removal if you are in an area that gets snow.
Make sure the guard rail can actually be grasped fully.
First ramp I built was for an older man and he couldn't get up the 1:12 slope. It wasn't even close. The second ramp I built for a six year old girl also at a 1:12 slope and the moment the ramp was declared "open" she bolted up and down it several times (maybe a thirty foot ramp with a switchback?) without even breaking a sweat.
Rich Beckman
Another day, another tool.
I stand corrected. 36" is the minimum for a ramp (and 30" rise is the max between landings). I was thinking about doors, where 32" is the minimum, and thought it would apply to a ramp as well.
I build 1 or 2 wheelchair ramps a month for a company that sells stair lifts and handicap accesories. I always build to the clients abilities(narrow ramps with low rails for people who can pull themselves along,wider ramps for people who need to be pushed or for motorised chairs) The things to watch for are to make generous level landings at turns and doorways and extra heavy duty construction if there is a chance that motorised chairs might be used because they can weigh a ton.I usually build at 1 in 12 slope sometimes more, sometimes less if space dmands it. cheers Rik
" I am a signature virus ,copy me to your sig line , resistance is futile "
Also check the max. length of the ramp before you need a landing (I think it is 30' which equals a 30" rise if using a 1:12 slope). The actual design of the ramp should be based on your clients needs. A strong 20-30 year old in a wheel chair can handle a 1:12 slope and may not need the landings while an older person may need a 1:15 or a 1:20 slope with a couple of landings to rest. A person with a walker or using a cane has different requirements. The same can be said about handrails. Use your clients abilities to design a ramp that works for them. Careful attention should be paid to how the ramps meets the ground. Small bump (1/2") seems like a mountain to some people in wheel chairs or with walkers.
Ok the person needs or can use a 1 : 10 ramp so you build that. Now 6 months latter the 1 :10 is to steep because person had set back. Now the person needs a 1 :12 latter on needs 1 : 15.
How about the person has now problem with the 1 : 12 but has a friend that visits from time to time that is weaker 1 :15 would better for the friend.
Why not build it to 1 :20 if you have the room and the money to do it.
That is my point (of course you would never build at 1:10). You should design for your clients abilities. I did a house for a quad and his needs and abilities generated the design (some were less than ADA, but most exceed ADA). One issue that needs to be considered during the design is the element of time and how the clients abilities will change over time. A 1:20 ramp is almost twice as long as the 1:12 ramp. My mother-inlaw hated long low slope ramps. She could not use the stairs but disliked having to walk twice as far. She could negotiate a 1:12 ramp and was much happier doing so. Another person may need 1:50 slope or a lift. ADA is minimum guide line developed using averages and input from competing sources (the disabled Vs the elderly Vs developers/contractors Vs businesses Vs banks Vs all of the other special interest groups) and it may not meet a specific clients requirements. In commercial work follow ADA (since you have no idea who will ultimately use the facility). In residential work follow your clients abilities.
1" rise per foot is the max here, with a minimum 48" width hand rail to handrail.
Bob
"Rather be a hammer than a nail"
Edited 12/28/2002 2:31:59 PM ET by Pro-Dek
Sorry, I posted the wrong pictures.Bob
"Rather be a hammer than a nail"
Nicely done Bob. Is that trex on the cap rail?.
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Thanks Piffin,Yes, the rail cap is 2x6 Trex and the decking is 5/4 x 6.Bob
"Rather be a hammer than a nail"
Check with the local Easter Seals organization for information.
http://ia.easter-seals.org/site/PageServer?pagename=IADR_homepage will take you to the Iowa branch homepage.