“Unlimited Density” is misleading in the Alameda Housing Element
The NIMBYs made the point to keep calling this one out over and over, that the housing element changes zoning to allow unlimited units with unlimited densities allowed in certain areas. NIMBY is gonna NIMBY, but the Housing Element terminology really helped them sell the fear.
I regret I didn’t ask that the city use the term “form-based limits” instead of “unlimited densities” in our new Housing Element. I honestly didn’t think it was a detail that mattered much. In hindsight, it would’ve stopped the NIMBYs from misleading folks and saying “unlimited units” were being allowed in Alameda.
Anywhere we removed any explicit DU/ac limits, it ended up getting referred to as “unlimited density” in the Housing Element, which in hindsight, is a little misleading. That “unlimited density” is really limited by the form limits that put practical constraints that really cap density instead of listing an explicit DU/ac in the code.
The fact is that we still have height limits (at least 40 feet for transit overlay), setbacks, lot coverage rules, and other design criteria. There are also practical limits to the minimum size you can make a unit of housing to be up to code and usable.
It’s hard to go much smaller than 500 square sqft and still meet code (which is around the size of a jADU). Atypical one-bedroom is closer to 750sqft. You can start to work out the math of what is possible from that to figure out the effective maximum DU/ac.
Let’s do a thought experiment with R-1 zoned areas but with a transit overlay (with so-called “unlimited density”) and calculate the likely number of units and DU/ac we will have on those lots:
An average Alameda R-1 lot is around 5000 sqft.
We have a 60% lot coverage maximum limit
That leaves you 3000sqft.
Subtract some for exterior features (usable interior square footage isn’t equal to exterior lot coverage usage). That’s maybe a 2500 sqft usable base floor.
The transit overlay gives you a 40-foot height cap anywhere in Alameda, which is around 3 stories. 2500sqft x 3 stories is 7500sqft usable floor space.
Ball parking here, but let's say you need 2000sqft for stairs/common areas leaving about 5500sqft for usable unit space.
So let's say you want to build some small one-bedroom apartments at 750 sqft apartment each. With 5500 sqft usable space at 750qft per apartment, you can build about 7 apartments. That’s 63 DU/ac and would end up looking something like this that we already have in Alameda.
I think I can safely say you won’t see anything bigger than that being built where there are allowed “unlimited densities” in R-1 to R-3.