educational estimating tool - not professional advice. a scenario, not a prediction. read the full disclaimer.
how much of your houston lot does the thoroughfare plan take
houston's major thoroughfare and freeway plan sets a right-of-way width for most thoroughfares and collectors. where one is narrower today, a lot that goes through a subdivision plat or a development plat can be asked to give the city a strip along its front. pick a neighborhood, then click a lot, or type an address, to see that strip.
scenario
the lot you clicked
click a lot on the map, or find one by address, to see its streets, the widths and the strip drawn on the lot.
neighborhood totals
| hyde park, private lots | (a) full width | (b) triggering lots only |
|---|
neighborhood by neighborhood
| neighborhood | private lots | (a) share of private land taken | (b) share taken | (a) lots losing over 10% | (b) lots losing over 10% |
|---|
the waiver and the variance
the amount. where an existing street is narrower than required and forms a boundary of the plat, the owner dedicates enough to provide one-half of the total required width (code 42-121(b)). on a major thoroughfare the required width is the lesser of 100 ft or the plan's classification (42-122). the full strip on this page is that figure with nothing waived, not what a given project would owe.
the waiver. the commission must waive the requirement when the applicant shows the project will not contribute to a significant increase in traffic on the street (42-121(b)).
the variance. the commission may grant a variance from chapter 42 on findings that include undue hardship depriving the applicant of reasonable use of the land, or a project made infeasible by unusual physical characteristics; economic hardship cannot be the sole justification (42-81(a)).
what triggers it. a subdivision plat (42-20) or a development plat, which new construction or enlarging a building generally requires (42-22). exempt from the development plat are a detached single-family unit on a platted lot that meets article iii (42-22(3)) and alterations adding 100 sq ft or less that do not encroach into the building line (42-22(2)). scenario (b) follows that line by appraisal class, which is a proxy: it leaves out hcad classes a1 and a2 and counts every other lot.
method
- boundary. the city's super neighborhood polygon, used whole. a lot is in if its centre point is.
- lots. harris central appraisal district parcels as published on the county's map service; stacked condominium copies counted once; lots in the exempt (x) classes left out. "private" means every other parcel.
- required width. the right-of-way figure in the plan's hierarchy code for each segment (t-4-100 reads 100 ft). on a major thoroughfare it is capped at 100 ft, because 42-122 requires the lesser of 100 ft or the classification (t-4-120 counts as 100). segments with two figures or "varies", freeways and tollways, and segments the plan marks proposed are not counted. a thoroughfare or collector with no code falls back to the city's minimum right-of-way by street classification (100, 80 or 60 ft).
- transit corridor streets. the city's minimum table reads no specific right-of-way minimum, and 42-122 has no row for them, so the code gives no required width. their plan figures are not counted: the strips those figures imply are listed apart and are in no total.
- sufficient width. a status on the plan layer that the city documents read do not define. 42-122 sets the width regardless of status, so these strips are counted, and the totals table also shows the land without them. in spot checks some segments marked sufficient measured well short of the plan width, so either the lot lines or that reading is off.
- today's width. measured on a line square to the lot's street edge, from the lot line through the street centerline to the first lot line across the street (median of three samples along the edge). a thin strip parcel between the lot and the street (15 ft or less on that line, long, with 20 ft or more of open street beyond it) is read through, and the width still runs from the lot's own line; any other parcel in between means no frontage. where no lot line is found across, twice the distance to the mapped centerline is used as an estimate, not a measurement, and the lot says so; in spot checks that estimate missed the lot-line width by up to 30 ft. a width still under 20 ft reads "not measured" and carries no strip.
- the strip. per side = (required - today) ÷ 2, from each side's own lot line: 42-121(b) asks for enough to provide one-half of the total width. this assumes the existing right-of-way is centered between the lot lines. the strip is clipped out of the lot line exactly, and corner overlaps are counted once. a strip under 1 ft is inside lot-line error; those lots are counted separately in the totals.
- no buildable footprint. houston has no zoning setbacks; chapter 42's building lines depend on the street class and options this page does not read per lot, so no footprint is drawn. the houston lot screen reads the building lines back for a tract you describe.
- which neighborhoods. inner-loop super neighborhoods where the plan's widenings cross existing lots. an area is published only if it passes the data checks: at least 200 private lots, at least 30 lots on a plan street, no more than 25% of frontages with no lot line found across the street, and measured widths that agree with the plan's own sufficient-width / to-be-widened status on at least 60% of segments.
sources
the other half of the question. this page shows what a lot could give up. what the same lot can now hold is how many homes a houston lot can make: run the lot there with the front of the lot moved back by the strip shown here.