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Applying Building Lot Coverage regulations

mendelman

mendelman

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A quick survey of my fellow Cyburbians:

If you have a maximum Building Lot Coverage (max coverage of buildings on a lot) in a residential district, how do you apply it?

Do you:
  1. Only count the total square footage of the footprints (foundations) of the buildings?
  2. Include the footprints and any cantilevered portions of a floor that is larger than the footprint?
I ask because our regulation is sorta vague - referring to the area of the zoning lot occupied by the principal and accessory buildings.

If you had an application for a new house with a footprint of 1,000 SF, but it had a second story of 1,200 SF cantilevered over the foundation, would you count the Building Lot Coverage as 1,000 or 1,200 SF?
 
I would call it 1,200. I interpret "footprint" to mean more like "shadow" exclusive of eaves. I also include anything requiring a building permit, so if there's a deck, and it's more than 30" above grade (which triggers the building permit requirement here) I count the deck, too.
 
With our code, the perimeter of the foundation defines the lot coverage. To make it interesting, though, we measure projections (cantilevers, eves and whatnot) for required setbacks.
 
We have none in residential, only some regs in the industrial district. Maybe a couple PUDs, but none in the straight zoning code.

I would think that ours, if any, would measured from the foundations only, meaning that bay windows, cantilevers and the like would not be included. However, we have been having trouble with houses being too big for the lots designed ("shoe-horned" as we like to call it) and such cantilevers have been known to extend into side yard easements causing problems down the road.

But I digress... I guess I didn't help.
 
Fat Cat

My current community is footprints of all buildings including garages or other out buildings (pole barns etc). But footprints only.
 
We definitely include any cantilevered space above. ISR is a big issue here because of drainage concerns, and if it can block water from going directly into the ground then it is impervious.
 
Footprint only.

I'd fight any township that tried to regulate this based on overhangs. The intent of this is to control impervious surfaces, obviously. An over hang doesnt apply.
 
Lot Coverage

mendelman said:
A quick survey of my fellow Cyburbians:

If you have a maximum Building Lot Coverage (max coverage of buildings on a lot) in a residential district, how do you apply it?

Do you:
  1. Only count the total square footage of the footprints (foundations) of the buildings?
  2. Include the footprints and any cantilevered portions of a floor that is larger than the footprint?
I ask because our regulation is sorta vague - referring to the area of the zoning lot occupied by the principal and accessory buildings.

If you had an application for a new house with a footprint of 1,000 SF, but it had a second story of 1,200 SF cantilevered over the foundation, would you count the Building Lot Coverage as 1,000 or 1,200 SF?
Click to expand...

Ahh, what an enjoyable issue! Funny this was asked because in our community this has become an issue in the last 4 months. Our code allows for an Area Exception for Lot Coverage over the required amount defined (for instance 20%) and we have had a bunch of requests which I think are not necessary (WHY? Because people need to buy bigger lots). Sorry for getting off topic, lets move on...Our department is quite liberal on this issue as we only count the following towards the lot coverage: any buildings on site, whether they are accessory or principle in nature.

Your second question as to the cantilevering over the foundation: we only count this total if that cantilever is actually supporting the roof (sort of). This generally occurs in instances where there is a large porch in the front or back of the house. If there are columns connecting down to the concrete, this is counted towards the total.

Back to the lot coverage definition. It varies around the communities here in the Milwaukee area. For instance, I believe that the Village of Pewaukee counts the driveway, buildings, basically any impervious surface towards the lot coverage total...I guess it depends on how much crap you want on the lots.

I would like to ask a question now. What is the percentage required for your lot coverage in the community where you are working? This is a subject that are now being required to research.

Hope this helps, and thanks for the help!:p
 
Mentos08 said:
I would like to ask a question now. What is the percentage required for your lot coverage in the community where you are working? This is a subject that are now being required to research.

Hope this helps, and thanks for the help!:p
Click to expand...
It depends on the district

SF districts:
RE & R1 (large lot SF) - max. 30% for buildings, 50% for all impervious surface
R2 & R3 (average lot SF) - max. 35% for just buildings on lots 6,000 sqft or greater; 40% for lots less than 6,000 sqft, 50% for all impervious surface

MF districts:
R4, R5, & R6 (2-family, low density MF, & mod density MF) - max. 35% for buildings, no impervious surface regs
R7 (high density MF) - max. 45% for buildings, no imperivous surface regs
 
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Here, lot coverage is defined as "the percentage of horizontal lot area that is occupied by all buildings on the lot, each measured at the outside of those exterior walls of the floor having the greatest horizontal dimensions."

What an odd way to measure this. I can think of many ways in which this definition would result in a lot coverage calculation that had no bearing on how much of the lot was developed or how much of the lot was covered in impervious surfaces. Most obviously, parking lots, walkways, driveways, porches, etc. are not counted. If the upper floors of a building are larger than the lower floors in horizontal distance, then the upper floors determine lot coverage. But what if the floors are the same size but are offset from one another? I just don't get the point of defining lot coverage this way, and don't recommend that anyone adopt this definition.

Our maximum lot coverage varies by zoning district and by whether the proposed use is permissible or requires a conditional use permit. The maximum lot coverage allowed varies from 10% to 80%, and in five zoning districts, there is no maximum lot coverage (although the setback requirements in all of these districts prevent 100% lot coverage). It's also worth noting that even where we don't have a maximum lot coverage, we do have a minimum vegetative cover requirement of 5-15%, depending on the zoning district.
 
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