We’ve got another item to add to our already lengthy list of current housing legislation in the works. The Board of Supervisors plans to vote today on a legislation sponsored by Supervisor Scott Wiener that would give a developer a density limit exemption if at least 20 percent of the units in a project are on-site affordable ones.

Currently, projects with 10 or more units are required to allocate at least 12 percent of the building’s units as below-market (or pay an in-lieu fee, or build off-site units). This new proposal hopes to incentivize the construction of more on-site units, according to a statement released by Wiener’s office.

If a developer opts to make 20 percent of the units in a building below-market rate, those affordable units won’t go towards the project’s density limits. This essentially means that a developer can add more market-rate units to a building if they allocate that 20 percent are for affordable housing.

It will be interesting to see how this one plays out. It sounds kind of a like a more developer-friendly version of Supervisor Kim’s housing balance ballot initiative, which requires that projects with more than 25 units make 30 percent affordable. But then again, its scope is likely somewhat smaller. We’ll be watching this to see what happens next.

Not to be added to our current housing legislation list but of interest, the Board also votes today to finalize the liquor license of Urban Putt. The Mission’s newest (and only) mini-golf spot is within the limits of the Mission Alcohol Special Use District, restricting the issuing of new liquor licenses, so the Board is voting today on whether or not to grant Putt an exemption. It’s likely to be a hole in one for the new business, since the Supervisors already gave it a preliminary approval.

As always, the agenda is a long one; you can see all the items here.

Correction: A previous version of this post stated that the Supervisor Wiener’s housing legislation is being introduced today. It’s actually being voted on today.