browser version · prague rooftop check
permit ai in pure html.
this is a client-side version of the permit assistant. describe a rooftop extension or similar building proposal, hit evaluate, and it gives you a structured risk readout, rule-by-rule notes, and changes that could improve the chance of approval.
what this version does
it runs fully in the browser, keeps the logic local, and does not need python. the current rules are focused on rooftop extensions in prague and especially the PSP topics that matter most for your case.
focusPSP 2024
typerule engine
best forroof extensions
runsoffline
proposal input
fill in the main facts. the app scores the design conservatively, so it is better as an early warning tool than a fake promise machine.
result
score updates after evaluation. this is a practical design filter, not a formal legal opinion.
not evaluated yet
run the check to get a risk score and a plain-language explanation.
waiting
once you evaluate, this panel will explain what is helping the design, what is hurting it, and what to change first.
built-in legal anchors
§ 18 to § 20 for height logic and what can be built above the regulated height, § 19 for stabilized-area context, § 14 to § 17 for line and frontage behavior, and § 21 for daylight / distance pressure on surrounding buildings.
how the rules think
sloped roof with attic is usually saferthe PSP allows a sloped roof above the regulated height if the roof stays within the allowed envelope. this is usually easier to defend than a full new floor.
setback helps a lotfor a setback floor, the street-facing wall and one more outer wall should step back by at least 2 meters. visually and legally, that matters.
character of the area mattersin stabilized areas, the height logic is derived from the prevailing surrounding form. even a technically possible roof can still be risky if it reads as too dominant.
neighbors can still stop the funif the design worsens light conditions for surrounding flats, that becomes a real approval risk even when the massing otherwise looks acceptable.
what to add later
site-specific zoning importpull actual zoning or regulatory height data for the exact parcel instead of relying only on user input.
shadow geometryrun a simple daylight proxy so the light-risk score is not based only on a manual dropdown.
doc exportgenerate a printable report with the score, assumptions, and recommended design revisions.