Background:
Rented homes house 37% of US households, and 65% of those are multi-unit, translating into >60 million Americans who rely on housing policies to protect their health from environmental exposures, including secondhand smoke (SHS) incursion from adjoining units. As tobacco addiction becomes concentrated among low income, ethnic and racial minority, chronically ill, and other vulnerable populations, who are more likely to reside in multi-unit housing (MUH), controlling MUH SHS is a key tobacco control disparities priority. Although the US Department of Housing and Urban Development (HUD) and many municipalities promote policies to increase the proportion of MUH that is smoke-free, less is known about how to support landlords with smaller portfolios serving low-income tenants.

Methods:
In Philadelphia, which has both the highest tobacco use and poverty rates of the 10 largest US cities, we conducted an online needs assessment survey in 2017 of members of the City's largest landlord association. Survey items measured current smoke-free portfolio, attitudes and experiences with tenants' tobacco use, and knowledge of Philadelphia's 2016 mandatory smoking disclosure law for MUH leases. Respondents were also offered technical assistance on transitioning to, or maintaining smoke-free rentals.

Results:
Of 226 respondents, 67% were unfamiliar with Philadelphia's disclosure ordinance, 40% allowed smoking in all or some units, and only 3% believed it was illegal to prohibit smoking in leases, but 34% were unsure, and only 61% knew it was legal. Respondents reported large (41%) or some (40%) demand for smoke-free properties, and most recognized benefits, including lower costs, inter-resident tension, and health risks. Drawbacks included resources required to transition properties and for enforcement. Over half of landlords with and without current smoke-free portfolios requested technical assistance.

Conclusions:
Results suggest that MUH initiatives such as disclosure ordinances could be enhanced by technical assistance to increase landlord adoption of smoke-free MUH.