A starting job
Pick a common call to fill the rise, slope, layout, and surface. Changing a kit never overwrites hours or material costs you have already typed.
The opening
Rise is the step from grade to the threshold. Slope is inches of run per inch of rise — 1:12 is twelve inches of run for each inch of rise. These are starting points, not a code opinion.
Hours and extras
Hours per 100 sf apply to the whole walking surface — sloped run plus every landing. Handrail and footing counts start from the geometry; change them when the site disagrees.
Materials and your costs
Payroll burden covers employer taxes, workers’ compensation, liability insurance, and paid time off. A lineal-foot special written on the run never sees it — or the landings.
Your bid
- Run
- Landings
- Walking surface
- Landings as share of walking
- Crew hours
- Loaded labor
- Materials
- Travel, mobilization, permit
- Overhead
- Total cost
- Profit
- Price per lf of run
- Price per walking sf
- Effective hourly rate
- Walk-away price
Where the hours go
Transparent arithmetic from your own inputs. The starting slopes, landing sizes, hours, and material rates are common ballpark figures, not an ADA determination, a building-code opinion, a permit, a warranty, or an engineering stamp. Time your own crews and replace them.
Hand the customer a proposal
The price above is for you. This is the page you print or save as a PDF and give to the customer — your details, their details, the scope, the deposit split, and a line for them to sign. Your business details are saved on this device so you only type them once; the customer’s details are never saved.
Everything on the printed page is text you typed or a number this calculator worked out. It contains no warranty, lien, or cancellation wording — those depend on your jurisdiction and your contract, and this tool is not the place to invent them.
Common questions
Why is a 24-inch rise ramp 146 sq ft of walking surface, not 24 feet of ramp?
Because a lineal-foot special counts the sloped run and stops there. At a 1:12 slope, a 24-inch rise needs 24 lf of run, which at 4 ft wide is 96 sq ft — but the top and bottom landings add another 50 sq ft at the default 5×5 size, for 146 sq ft of actual walking surface. The lf number a competitor quotes off of never included the two landings the ramp can't function without.
Why does a switchback sometimes need an extra landing that a straight ramp of the same rise doesn't?
Because a switchback needs a turn platform, and if the rise is short enough that no rest landing is already required between the top and bottom landings, the turn itself still has to happen somewhere — so the calculator adds one landing specifically for that case. A straight run at that same short rise needs only its top and bottom landings; the switchback layout is what forces the extra one.
Why does aluminum cost so much more per square foot than wood, and why does it have no framing cost?
A modular aluminum kit prices decking at $28 per sq ft against $4.50 for pressure-treated wood, but it carries zero framing cost because the modular structure is the surface — there's no separate joist-and-post build the way wood, composite, and concrete all need at $4–$6 per sq ft. Aluminum also cuts labor roughly in half, at 1.8 hours per 100 sq ft versus 3.2 for wood, so the two costs move in opposite directions.
Why does the calculator suggest zero handrail footage below a 6-inch rise?
Because that's the common starting threshold below which handrails are often not required on a residential ramp — the suggestion is editable, and the shop can still add rail hours and footage for any rise. Above the threshold, suggested handrail length covers both sides of the run plus one side of every landing, which is why landing count feeds into rail footage as well as surface area.
Why does the footing count grow with both the run length and the number of landings?
Footings come from three sources added together: a fixed pair at the house, a pair at every landing, and posts spaced along the run itself — by default one pair roughly every 8 feet. A longer run needs more posts along its length independent of landings, and more landings need their own support independent of run length, so a switchback with an extra landing on a long run can need noticeably more footings than a straight ramp of the same total rise.
Do this calculator's defaults match ADA ramp requirements?
The defaults mirror the numbers most often cited from the ADA Standards for Accessible Design: a 1:12 maximum running slope, a landing at least every 30 inches of rise, 5×5 ft (60×60 in) landings, and handrails once rise passes 6 inches — which is exactly what this calculator starts from. Matching those numbers is not the same as certifying ADA compliance: the standard also covers surface texture, handrail height and grip diameter, edge protection, and cross slope, none of which this calculator checks. Verify the built ramp against the full standard, your local building code, or the authority having jurisdiction before calling a job compliant.
Does a ramp at a private home have to meet ADA requirements?
Not automatically. The ADA's design standards are a legal requirement for places of public accommodation and commercial facilities; a single-family home generally sits outside that reach unless it was built with certain public funds, falls under a state or local accessibility code, or the ramp is a condition of a program such as a VA or state home-modification grant. Plenty of homeowners ask for “ADA” anyway because it is the slope everyone recognizes, which is why the defaults above start there — confirm which rules actually apply to your job before pricing to a different slope.