Post #1262: Rezoning to allow even larger houses in the Town of Vienna

Posted on September 23, 2021

Context in brief

As everyone in the Town of Vienna should know, the Town is redoing all the zoning.  This includes not just the commercial districts, but the residential areas as well.

You’re probably not reading this just to hear me describe how the Town of Vienna got to this point.  And why you need to start paying attention now.  If you want that, read the “Background” section at the end.

Here’s what you need to know.  The Town government, including our elected and appointed officials have, together, determined that the Town of Vienna needs More.  More residents, more medium-density housing, more duplexes, more building.  The Town is considering many substantive changes to the zoning, all of them in the direction of More.

Those zoning changes are going to be voted on soon. 

If you just glance at what they say they are doing, you’ll will be given the impression that it’s all routine, and there’s not much happening.  Just “an effort to clarify, simplify, reorganize, and update” the zoning, per the Town’s websiteYou’ll be told, in effect, it’s nothing, don’t worry about it. 

So you’d best start paying attention to what’s going on.

Today’s topic is the proposed change in lot coverage rules, for the residential areas of Vienna.  And, consistent with what I just said, it’s all about More.  In this case, this boils down to the potential to allow bigger houses, on the same lots, in Vienna.  This, despite the fact that you will not find any written materials from the Town of Vienna that just plainly say that.

Bigger houses in Vienna?  Background.

I went though the background on this more than half a year ago, in Post #1087 and two earlier pieces referenced in that post.  This is really an update of my prior post, and you might want to start there.

In a nutshell, houses can only cover 25% of the lot in Vienna.  Of the buildable area, only 25% can be covered by house, driveway, porches, sheds, garages, and the like.  That’s been the rule for about 70 years.

In that distant past, that typically wasn’t a binding constraint.  Even on a modest quarter-acre lot, the rule allowed the footprint to be about 2700 square feet.  In the 1950’s-era neighborhoods (such as the one I first moved to), typical house footprint was around 1200 square feet.  The lot coverage rule was rarely an issue.

Only in the past 20 years or so have builders routinely built every new house to cover that entire 25%.  And that — the fact that every new house built in Vienna is now built to be absolutely as large as it can be  — that’s that’s what set this whole thing off.

In the pandemic, some Vienna homeowners wanted to expand their houses to include a screened porch or similar living space, and found out that they couldn’t.  They’d bought a new house, in Vienna that had been built sometime in the past couple of decades.  And so, it was as large as it could possibly be.  (That’s the unwritten rule, here in Vienna:  All new buildings must be absolutely as big as they can possibly be.)

Separately, in the current context, the lack of such an “outdoor amenity” handicaps the resale value of the home.  So it’s not just about comfort during the pandemic, it’s about materially depressing resale value due to the lack of “outdoor living space”.  Moreover, even if you don’t build that amenity, if the right to build that exists, that adds to the resale value of the home.  And, conversely, the known lack of that right detracts from resale value.

Let me put aside how I feel about people who would invest $2M in a house without knowing the rules.  I mean, stuff happens, but that connotes a level of wealth well beyond my personal experience.  Let me just treat this as a significant number of folks who were completely unaware that the very large houses they bought were as large as could legally be built on those lots.  And are now agitating for the rules to be changed to accommodate their mistake.

Councilwoman Patel heard their plea, and championed this issue in front of Town Council.  Expand the lot coverage rules to allow more “outdoor living spaces”.  You can read some contemporary reporting here.

At the time, Councilwoman Patel said that her interest was in allowing these people to build porches, and not in allowing larger houses in Vienna.  But, as I see it (below), that was to a large degree, wishful thinking.  In reality, the only options for change that Town Council are being given are for larger houses, and for even larger houses.

Why not just do this with zoning variances?

A variance is a one-off exception to the zoning rules.  Per the Commonwealth of Virginia Code, emphasis mine:

"Variance" means, in the application of a zoning ordinance, a reasonable deviation from those provisions regulating the size or area of a lot or parcel of land, or the size, area, bulk or location of a building or structure when the strict application of the ordinance would result in unnecessary or unreasonable hardship to the property owner, and such need fora variance would not be shared generally by other properties, and provided such variance is not contrary to the intended spirit and purpose of the ordinance, and would result in substantial justice being done. It shall not include a change in use which change shall be accomplished by a rezoning or by a conditional zoning.

I think the answer is that a homeowner is free to ask for a variance, to be able to put up a porch in excess of the 25% limit, in response to the pandemic.  So you’d think that the Town could finagle this by inserting a clause in the current code to say just that.  The pandemic shall be deemed a sufficient justification for allowing these porches.  Then, let anybody who wants to exceed the 25% limit, to build a porch, apply for a variance, and be granted one.

I’m not a lawyer, but I think the clause in boldface trips that up.  And probably should.  If you expect a large class of people to take advantage of it, it’s a back-door rezoning, not a variance.  A variance should be, by definition, a unique one-off exception.

By contrast, if there’s a house with an oddly-shaped lot, where (e.g.) setback requirements prevent building a porch, the Town can O.K. that through the normal variance process.  (Here’s an example of one that was granted in Vienna (.pdf)).  That one case is not indicative of a broad class of houses that would then qualify, so that porch can be allowed as a variance.

But letting people on rectangular lot add a porch that exceeds that 25% limit wouldn’t be allowable, because there’s a broad class of people to whom that exact variance would be potentially applicable.

Bigger houses in Vienna?  Analysis

Source:  Town of Vienna website.

Vienna Town Council and Planning Commission are now looking at three options for increasing lot coverage in Vienna.  I will call these, in order, from left to right:

  • Option 1:  No change
  • Option 2:  Targeted expansion.
  • Option 3:  Untargeted expansion.

Before we start, recall that the original goal of this was to allow people to add a screened porch or similar, even when their house already uses the full 25% allowable lot coverage.  Let me assume that we are bound and determined to do that.  (Which is, by the way, far from a settled matter.)  My goal, in evaluating Option 2 and Option 3 is to see which will create the smallest expansion of the total volume of the house.  In effect, I’m looking for the options that results in accommodating the people who didn’t realize their house maxed out the lot coverage rules, while making the smallest practical change in those rules.

Point 1:  Under current law, the house has to be considerably smaller than 25% of the buildable lot.

Under current law, a house, driveway, and any outbuildings (e.g., detached garage) and other paved areas can cover no more than 25% of the lot.  (Decks don’t count toward that 25%, but instead are limited to an additional 5%.)

The key here is that the sum total area of all of those has to fit within the 25% limit.  The practical result of that is that the footprint of new houses in Vienna is currently limited to significantly less than 25 percent of the lot.  That’s because you have to fit the house, driveway, and every other paved or roofed surface into that 25% limit.

Point 2:  Driveways are key.  Remove the driveway from that 25% limit, do nothing else, and new houses will be about 25% larger than they are now.

In particular, I’ll point to the driveway as a key element there.  You might not need a patio and so on.  But you have to have a driveway.  The setback rules keep the front of your house quite a ways from the road.  Which means that in most cases, under current rules, you have to reduce the size of the house substantially, just to accommodate the required driveway.

In Post #1087, I used my neighbor’s house to estimate just how large the driveway effect is.  That’s what I would call typical new construction.  It’s on a rectangular lot, it runs right up to the 25% coverage limit, and the only significant feature other than the house is the driveway.  You can see that post for the full calculation.

The upshot is that the driveway takes up about 5% of the buildable lot.  If the driveway were taken out of the 25% limit, and no other changes were made, builders could (and would) increase the size of the house to fill the complete 25% lot coverage limit.  And that, by itself, would increase the size of the house by 25%.  (That is, 25% / 20% = 1.25 =25% increase).

And that’s easy enough to visualize.  Look at any new house with a front driveway.  Fill that driveway with a full-height addition to the house.  That’s how big the house would be, if the driveway were removed from the existing 25% lot coverage limit.

Point 3:  Under that analysis, Option 2 is  the least-harmful way to accommodate a large screened porch.

If you are bound and determined to increase lot coverage to allow for “outdoor living space”, then under the analysis above, Option 2 should result in the least expansion of the house-proper (i.e., excluding the screened porches, etc.)

Under Option 2, you still have to count the driveway in with the house itself.  In my “typical new construction” example, that then continues to limit the house-proper.  You have to have a driveway, I think.  In what I believe to be the typical rectangular-lot case in Vienna, the house still couldn’t exceed about 20% of the buildable lot.

In addition, Option 2 specifically identifies an intent to include true “outdoor” living space.  That’s a screened porch (not an enclosed porch).  A covered deck (so, presumably, the floor has to be open deck-style boards).  Or a patio.  Those are obviously hard to enforce in the long run.  But that seems to be the intent.

Finally, that is clearly and explicitly written as single-story structures.  Given how the world works, you can bet that somebody will try to game that.  Is a 25′ cathedral ceiling still a single-story structure, and so on.  There’s scope for somebody to do something obnoxious, without a clearly specified total height limit.  But at least the intent is clear.

So with this one, again, looking at my neighbor’s house, I think I know exactly what I would get.  He’d have the right to add a single-story screened porch, roughly the size of the driveway, onto the back of the house.  Or, if that was built new, it’d have come with that already built.

I’m across the street from him, not adjoining his back yard.  But, honestly, I don’t think that would be terrible.  For me.  There are issues of runoff, and the potential for further creep.  But, honestly, I don’t think I’d be picketing Town Hall over that one.  That seems to be in the spirit of a reasonable accommodation.

Now, you might say, wait a minute.  That reasoning is fine in your neighborhood, where the only thing sticking out from the big new houses is the driveway.  But in a neighborhood with (say) much larger lots, where the builders routinely added a back porch to the house, won’t this allow for much larger houses there?  Or ditto, for a large patio?

And the answer to that is yes, it would, to the extent that builders routinely built a large screened porch onto new houses.  I’m not at all sure how common that is, but my impression is that most existing outdoor amenities of this type, on new houses, would not fit my notion of what a screened porch is.  Most are sunrooms, three-season rooms, and similar.  They are glass-walled extensions of the home.  But this is something that you’d have to give some consideration to.  I’m not sure I have a clear answer to it.

You might want to regulate it as to shape, to avoid encroachment on the neighbors.  I immediately envisioned a screened porch that ran along the back wall of the house.  Tucked up against the back of the house, it would blend in with the house.  But there’s nothing to prevent a screened porch constructed as a a long extension running perpendicular to the house, as long it didn’t encroach on setbacks.  The first would have minimal impact on the neighbors and the look of the neighborhood. The second, not so much.

I’d like to see somebody take a hard look at this in terms of ways to game it.   In particular, I’d point to the lack of a clear definition of “screened porch” as a potential for creep.  (Or “covered deck”, for that matter).  We all know what a screened porch is, but what matters is the legal definition of a screened porch.  And I have yet to find one.

For example, my screened porch has brick kneewalls, then screening from there to the roof.  Would that be allowed?  Is a sun room a screened porch, as long as the windows can be opened to allow it to function as a screened room?  Is it a screened porch if the walls can be opened up to allow air in, but can also be closed to make it a “three season porch”?  In other words, absent a clear legal definition, try to figure out all the different things that might be claimed as a “screened porch”, and figure out how to rule out the ones you don’t want.

Otherwise, my claim is that for typical new construction in Vienna, at least on the small-to-mid-sized lots, where I don’t see much in terms of large patios or screened porches or covered decks now, the impact of this would be fairly clear.  The need for a driveway would continue to pin the house size down at somewhere around 20% lot coverage.  And then you’d get one-story screened porches (or covered decks, or patios) amounting to 5% of lot coverage,on top of that.

Point 4:   Moving the driveway in Option 3 is asking for an increase in house size.  It neither achieves the goal nor keeps the size of the house-proper constant.  It flunks.

Option 3 has a lot of moving parts.  The percentages change, the location of the driveway changes, covered decks are now somehow separate from screened porches, and so on.  To my eye, it’s a jumbled mess.

Let me just point out the obvious, using my “typical new construction” example.  Under this option, a builder can simply come in and build houses that are 15% larger than they are now.  Full stop.  (That’s 23/20 = 1.15 = 15% larger).

In other words, people can now take advantage of Option 3 without having to provide any outdoor living space.

For that reason, this one flunks, straight-up.  If you are going to change the law specifically to accommodate outdoor living space, you can’t write it so that you can take advantage of the new limits without providing new outdoor living space.  That’s pretty much the definition of a loophole.


Those of you who have ever worked in a supporting role in a government agency may recognize this set of choices as a classic “Sears Strategy”.  This is named after the retailer Sears Roebuck, renown for their retailing approach of offering a set of options as “good, better, best”.  This allowed Sears to steer consumers’ choices, as roughly 90% of middle-class consumers will take the “better” option, more-or-less no matter what it is.

In a policy choice context, the iron rule of a Sears Strategy is never to give decision-makers more than three options.  Executives get confused if you have more than that.  And always make Option 2 the one you want.  Do that, and 90% of the time, the choice will be the middle option.

Deeper Background

Finally, for those who care (most don’t), here’s some deeper background on how Vienna got to this Town-wide rezoning.

As everyone in the Town of Vienna should know, the Town is redoing all the zoning.  This includes not just the commercial districts, but the residential areas as well.

If you boil it down, virtually everything about the proposed zoning changes is about more.  More people — setting the stage for a substantial increase in the Town’s resident population.  More apartments, condos, and other medium-density housing.  More duplexes, to the point of creating incentives to build duplexes.  And more building — allowing and encouraging larger buildings, while minimizing things that might restrict building size, such as parking requirements.

Nobody ever actually asked existing Town residents if they want this.  In particular, whether they want many more people living here.  My guess is, parents of school-aged children might object to that, at least those who attend the relatively crowded public schools.

The only true random-sample survey of residents that the Town did on this topic was years ago, where they asked a super-sweet mom-and-apply pie question as part of the National Citizen Survey (,pdf).  Something like, is it important for Vienna to maintain a vibrant downtown?  Unsurprisingly, most respondents answered that it was.

To the contrary, Town staff vehemently reject any notion of doing a proper random-sample survey of the residents.  See, e.g, Post #462.  (This, after two different Town Council members suggested going that route).  In my experience, if you fight against using the obvious, accurate, cheap, and industry-standard approach, that’s because you won’t like the answer.

Instead, as I posted some time ago, the Town is absolutely committed to making decisions about $5,000,000,000 worth of property informed by a $400 self-selected internet survey (Post #1090).  Which this Ph.D. economist humbly suggests is not a very smart way to do business.  Once upon a time, we had Town Council members who were independent enough to say the same thing.  But no longer.  So now I’m the only one left who is willing to keep saying that.  Despite how obvious it is.

Because, to state the obvious, you use that sort of survey not to gather opinion, but to validate what the vested interests want to see.  Those who have close and professional interest in the results will answer, because they have money on the line.   They’ll organize to make sure all their friends give the “right” answers.  In our case, we had a local real estate agent use her role as moderator of a (the largest?) Vienna Facebook group instruct people on how they should respond to the Town’s survey.

By contrast, what you’ll probably find, if you make the effort to get a true cross-section of opinion of Town of Vienna residents, is that, overwhelmingly, Vienna residents would like any re-do of the downtown area to generate more green space and more open space.  That seems fairly plausible, doesn’t it?  But how do I know that?  I asked them, in a straightforward, random-cross-section manner, as summarized in Post #379.  Something the Town will not do.

In any case, that “more green and open space” thing ain’t gonna happen. Never was.  See my prior post on Town of Vienna rezoning.  Hence, no survey can be conducted that might show that.  Because disagreement does not exist in the Town of Vienna any more (Post #1132).  And we’re all supposed to pretend that will lead to good decisions.

I need to say one more thing, which is that you can’t rely on the Town’s bland description of what they are doing.  Not if you want a clear idea of what’s actually at stake.  You need to look at the details.  Let me walk you through that, in case you don’t quite believe me.

From the outset, Town government has downplayed the scope of what is happening.  When this process was first introduced to the public at the  1/7/2019 Town Council meeting, the Mayor at the time unambiguously stated that this “cleanup” of Town zoning was going to change nothing about the zoning itself.  Again, clearly stated, there was not even any intent to change the zoning. 

From the posting cited above, just after the 1/7/2019 Town Council meeting:

Despite the fact that we are “selling it” to Fairfax Count as an economic development measure, the Mayor flatly said “We are not changing any of our zoning.” Again, “Our intent is not to change anything.” So that Mayor characterized this as a purely technical “clean up” of an existing set of somewhat messy regulations.

If you read the staff description of this, in the meeting materials for that kickoff Town Council discussion, the rezoning sounded completely innocuous.  Let me just copy that in here:

The goal of this proposed project is to reorganize the subdivision and zoning ordinances so that regulations are logically organized and easy to understand through use of plain language, charts, tables, and illustrations. In addition, the subdivision and zoning ordinances should be updated so they are in compliance with state statutes and recent Supreme Court decisions with regard to sign regulations. The updated ordinance should be consistent with the Town’s Comprehensive Plan and address areas where the Code has been silent and zoning determinations have been made over the years by the Town’s zoning administrators or where regulations are currently lacking, e.g., parking requirements for all uses.

Reorganize, make it comply with the law, maybe tweak the parking requirements.  Dull stuff, right?  Ho-hum.

But if you were to dig around, and obtain the actual scope of work for this task (which was not actually posted with that Town Council meeting, you just had to have somebody clue you in on where to find this .pdf draft copy), you would find that, to the contrary, absolutely every aspect of zoning in the Town of Vienna is up for grabs.   I went over that, with references, in my last post on this topic (Post #1257).

But here’s a weird one.  Last week, I mentioned that the Town’s official description of this process, on their website, referred to it as “a tune-up” of the existing code.  That language is consistent with all the prior rhetoric minimizing the seriousness of the proposed changes.  But that language appears to be gone, no longer in the Code Create section of the Town’s new cartoon-based website.  (Or, at least, I can no longer find it.)  That’s my mistake for not taking a screenshot.  Instead, let me quote the current description of the rezoning, from this TOV web page:

The Town of Vienna is leading an effort to clarify, simplify, reorganize, and update the Town’s subdivision and zoning ordinances, Chapters 17 and 18 of the Town Code.

Seriously, who could object to clarifying and simplifying the code?  And that’s exactly why that bland description is there.  If they’d said something more accurate, such as “rewriting the commercial zoning to encourage construction of mixed-used apartments, condos, and similar medium-density housing along Maple Avenue”, that might have caught somebody’s attention.  Maybe “allow and encourage creation of duplex housing”, that might have caught your eye.  And so, clarify and simplify it is.

Be that as it may.

Here’s what you need to know.  The Town government, including our elected and appointed officials have, together, determined that this is what the Town of Vienna is going to get:  More.  More people, more medium-density housing, more duplexes, more building.  The only thing to be decided, from the government perspective, is just how much more will be allowed.

Those zoning changes are going to be voted on soon.  If you just glance at what they say they are doing, you’ll will be given the impression that it’s all routine, and there’s not much happening.  Just an effort to clarify and simplify the zoning.

You’ll be told, in effect, don’t worry your pretty little head about it. 

So you’d best start paying attention to what’s going on.