MD HB339

Landlords of apartment buildings with four or more units must provide air-conditioning in residential rental units, with requirements taking effect June 1, 2025 for new construction and October 1, 2025 for units undergoing renovation that includes replacement or substantial upgrade of electrical or heating systems

From June 1 to September 30 each year, landlords must maintain indoor temperatures at no greater than 80 degrees Fahrenheit at 3 feet above floor level in each habitable space

For tenant-controlled AC systems, landlords must ensure the system is in good working order and capable of maintaining the required temperature; for landlord-controlled systems, landlords must actively maintain the temperature

Properties listed on the National Register of Historic Places are exempt from the requirements

The law applies prospectively only and does not affect buildings with permits issued before the effective date