DOB Partial demolition versus new build

Easier to get DOB permits if its considered an alteration vs. new construction. Rule I remember from years ago was that if you kept two exterior walls, anything you built would be considered an alteration. At least one benefit of calling it an alteration is that your building may be grandfathered from existing zoning e.g. you can keep the original size even if current zoning would otherwise require a smaller building. Not sure of current rules.

I remember when there was a huge fire on Broadway and they developed 77 Bleecker Street as a "renovation" even though pretty much the only thing that remained was the cast iron facade facing Broadway. I am pretty sure this was done so that they could get a j-51 tax abatement, as opposed to 421a, because the benefits of j-51 far exceeded those of 421a.

In some areas it is because of things like lot coverage and setbacks, where in a renovation those items tend to be grandfathered in, but it new construction you have to abide by the current zoning.

Yes, 30. It's often more about maintaining the existing non-conforming footprint and occasionally about keeping a non-conforming use.

Interesting. Thanks ximon and 30yrs!

If a property is doing a partial demolition for a re-build (files Alt type 1 / Alt-CO), is the property considered a new construction or still considered an existing property (since remains of the original property still exists)? Wonder if there's tax incentive that one might qualify for if the property is an existing home (e.g. Energy Efficient Home Improvement Credit)