In the latest bid to address pent-up demand for affordable rental housing, Mayor Kirk Caldwell signed into law this week a nothing-ventured-nothing-gained type of measure. Bill 7 holds potential for success, although at least one provision could be challenging in car-centric Honolulu.

The new law makes way for recasting of low-rise walk-up apartment buildings — a popular construction project in 1960s and 1970s — as a stable affordable-housing inventory. It allows some buildings to grow vertically — up to six stories high — and allots a tighter floor-area ratio to make room for more apartments.

The five-year pilot program offers property owners a bunch of carrots. In addition to greater density and taller heights: a reduced setback requirement, waivers from building permit application and wastewater facilities charges, no park dedication fees, a 10-year tax waiver on property taxes, and, ahem, no required parking.

One general contracting firm poised to take up the offer maintains that bike-sharing and car-sharing can serve as viable alternatives to the standard requirement of one stall per unit. With the city hoping to see 500 units built annually, time will tell whether residents opt for sharing-transportation or hold onto their cars, cruising already crowded streets in search of curbside parking.

In exchange for this redevelopment, property owners must agree to rent 80% of new units to people making 100% of Oahu median income as defined by federal guidelines. In 2019 that means renting to a two­-income couple making a maximum of $93,300 annually, a two-bedroom unit for $2,100 a month.