Start with the rise, not the ramp. Measure how much height you need to clear at the entrance, then let that drive the length. A gentle slope of about 1:12 is the standard we point people to, because a steep ramp that's icy in February is a fall waiting to happen. Calgary's chinooks make things worse than a steady cold snap would; snow melts, refreezes overnight, and a smooth surface turns slick. Insist on a non-slip surface, sturdy handrails on both sides, and a flat, level landing at the top so your parent can pause and open the door without balancing on an incline.
Housing here shapes the choice. Many older homes in the inner-city communities like Killarney, Inglewood, and Crescent Heights sit up on a few steps with tight front yards, so length matters and you may need a switchback. Split-levels and walkouts in the newer suburbs can involve a longer run. For condos and townhomes, check with the board before anything is fixed in place. In our experience, that's where a modular aluminum ramp earns its keep: it's removable, it doesn't rot or need repainting through wet springs, and you can resell or relocate it if needs change.
Our advice: for most Calgary families, choose a modular aluminum ramp installed by a company with real accessibility experience over a permanent wood build. Wood looks warmer and can cost less up front, but it gets slippery, needs upkeep, and holds you to one spot. Modular is quicker to install, safer in ice, and keeps its value. The trade-off is honest: aluminum can cost more at the start and looks more clinical than a wood ramp that matches the porch. When you're comparing installers, confirm they're licensed and insured, ask what the warranty covers, and ask how fast they respond if a handrail loosens or a section needs adjusting after a hard winter.