What happens if you skip the permit (and you needed one)
- Stop-work order from Florissant Building Department costs $250–$500 in fines, plus the city will require you to remove the new roof and re-pull the permit at double the standard fee ($300–$700 total).
- Insurance claim denial: if a storm or leak damage occurs within 5 years and the adjuster discovers unpermitted roofing, your homeowner's policy can refuse to pay — potential loss of $10,000–$50,000.
- Resale disclosure: Missouri law requires you to disclose unpermitted work to a future buyer; buyers often demand a $5,000–$15,000 price reduction or require a retroactive permit (which may fail inspection after the fact).
- Lender or refinance block: if you refinance or take a home equity loan, the title company's inspection may uncover unpermitted roofing and freeze the transaction until a permit is obtained and passed.
Florissant roof replacement permits — the key details
Florissant's primary rule is IRC R907.4: if your roof currently has 3 layers of shingles or other covering, you must tear off all existing material before applying new shingles. This is not negotiable in Florissant's interpretation — the city's permit application explicitly asks 'How many existing layers?' and the reviewer will cross-check this against the IRC requirement. If the field inspection (after tear-off begins) reveals a 3rd layer that wasn't disclosed, the roofer will be issued a stop-work order and must remove all layers down to the deck. Many homeowners and even some roofers underestimate how many layers are present; Florissant Building Department staff recommend a pre-permit roof inspection by either the roofer or a third-party inspector (cost: $150–$300) to confirm layer count. The IRC also requires that any roof with 2 layers cannot have a 3rd layer added — overlay is prohibited in that case. Florissant enforces this strictly, so an overlay quote is only valid if the roof currently has 1 layer or fewer.
Underlayment and fastening specifications are critical in Florissant's plan review, especially for asphalt shingle replacements. IRC R905.2.8.2 requires underlayment on all slopes; in Florissant's cold climate (Zone 4A, 30-inch frost depth), ice-and-water shield must be installed in the eaves area extending at least 24 inches inside the exterior wall line (per IRC R908.3). The permit application or your roofer's plan documents must specify the underlayment type (e.g., ASTM D226 Type II felt or synthetic) and fastening pattern (e.g., 4-6 nails per shingle, 3/8-inch below the sealant strip). If the permit documents don't specify these details, the Building Department will ask for clarification before issuing the permit — adding 2–5 days to review. Some roofers submit a generic one-page spec sheet that Florissant rejects; the city prefers a roof plan or a detailed narrative that ties fastening and underlayment to the IRC sections. This is a common delay point, so confirm with your contractor that they will provide this documentation.
Florissant's permit does not typically require structural evaluation for a like-for-like material replacement (standard asphalt shingles). However, if you are changing roof material — from asphalt shingles to metal, tile, or slate — or if the inspection discovers structural deck damage during tear-off, a structural engineer report is required before permit sign-off. This can add $800–$1,500 to the project cost and 1–2 weeks to the timeline. Partial roof replacements (repairs covering 25% or less of the total roof area) do not require a full permit; they are classified as repairs and are exempt if they are patching fewer than ~10 squares (1 square = 100 square feet). Repairs over 25% are treated as replacements and require a permit. The distinction is important: if your roof needs shingles replaced on one side of a hip or gable, that may be a repair; if you're replacing both the north and south faces, that's likely over 25% and triggers the permit requirement. Florissant's reviewer will ask for a sketch or photo showing the affected area to determine which category applies.
Gutter, downspout, and flashing-only work is exempt from permitting in Florissant, even if the entire gutter system is replaced. However, if the flashing work is part of a roof tear-off-and-replace project, it must be included in the roofing permit and inspected at the same time. Re-roofing over existing flashing (without tearing off shingles) is also exempt, as long as the fastening and seal are adequate. Some contractors try to split a project into 'flashing work' (exempt) and 'roofing work' (not) to avoid a full tear-off; Florissant's inspectors watch for this and will require a new inspection and potential remediation if the existing shingles are three layers and the flashing work revealed that condition.
Permit fees in Florissant are based on the total roof area (in squares) and are roughly $2–$4 per square, with a minimum of $150. A 3,000-square-foot house (roughly 30–35 squares) would pay $150–$250 for the base permit, plus $50–$100 if structural review or additional inspections are needed. Inspection fees are typically included in the base permit cost. Timeline: a like-for-like tear-off-and-replace with good documentation submits Monday morning and receives approval by Thursday afternoon (3–5 business days); projects with material change or structural questions take 1–2 weeks. Inspections are usually scheduled within 2–3 days of a phone call to the Building Department; most are scheduled on a first-come, first-served basis, so plan ahead if the roofer wants to start work immediately after permit issuance.
Three Florissant roof replacement scenarios
Why Florissant strictly enforces the 3-layer rule — and what it means for your budget
The 3-layer cap in IRC R907.4 exists because each layer of roofing adds weight to the roof framing, and building codes assume that older roofs with multiple layers may conceal structural problems or exceed the design load of the framing. In Florissant, the Building Department applies this rule without exception: if a roof has 3 or more layers, tear-off is mandatory, even if the homeowner and roofer both agree that an overlay would be 'fine.' The city's logic is sound — a 30-year-old roof with 3 layers may have moisture trapped between layers, hidden deck rot, or compressed underlayment that will fail faster than a proper tear-off-and-replace. However, the practical effect is that the cost difference between an overlay and a tear-off is substantial: overlay might cost $5,000–$7,000, while tear-off-and-replace costs $10,000–$16,000. Florissant's strict interpretation also means that some homeowners and roofers are surprised when an overlay quote is rejected at permit time, after the homeowner has budgeted for the cheaper option. To avoid this, obtain a roof inspection before requesting quotes, or explicitly ask the roofer, 'Can this be done as an overlay, or will the city require a tear-off?' If the roofer is unsure, the roofer should contact Florissant Building Department's permit intake (typically a 10-minute phone call) to confirm.
Florissant's history of roof failures and ice dam issues in the late 2000s and 2010s also influenced the city's emphasis on proper underlayment and ice-and-water shield. Climate Zone 4A winters bring freeze-thaw cycles, and the 30-inch frost depth means that water on a roof can freeze and create ice dams if underlayment is inadequate. The city's permit reviewers therefore also scrutinize ice-and-water shield specification during plan review: they want to see it extend at least 24 inches from the exterior wall line, per IRC R908.3. Roofers who submit incomplete or vague specifications (e.g., 'ice-and-water shield as required') may receive a request for clarification. This adds a few days to review but is a one-time conversation. Once clarified, the permit is typically approved.
Budget for a tear-off as the baseline in Florissant if your roof is 20+ years old. A single-layer roof less than 15 years old is usually a safe bet for an overlay, but verify with a roofer or inspector first. The cost difference may be justified: a proper tear-off removes hidden moisture and rot risk, and a new underlayment layer provides better protection in Florissant's cold climate.
Permit timeline and inspection scheduling in Florissant — how to avoid delays
Florissant's Building Department typically processes roofing permits within 3–5 business days for straightforward like-for-like replacements. The roofer (or homeowner, if owner-builder) submits the permit application in person at City Hall or online via the city's portal. If submitted online or before 10 a.m. in person, the permit is usually reviewed the same day or the next day. The reviewer checks the application for completeness, roof area, layer count, and material specification. If all details are clear and no structural changes are proposed, the permit is issued with a boilerplate approval and inspection requirements. However, if the application is incomplete (e.g., missing layer count, roof area in square feet, or underlayment spec), the reviewer sends an email or calls the roofer requesting additional information — this can add 2–5 days. To streamline, have your roofer prepare a checklist before submitting: (1) roof area in squares and square feet, (2) number of existing layers, (3) new material type, (4) underlayment type (e.g., ASTM D226 Type II felt), (5) ice-and-water shield installation area (24 inches from eave), and (6) any structural changes or deck repair estimated cost.
Once the permit is issued, inspections are scheduled on a first-come, first-served basis. Most roofers call the Building Department the day before they tear off shingles and request an inspection for the following morning or afternoon. Florissant's inspectors typically respond within 24 hours and schedule an inspection within 2–3 days. The deck inspection (after tear-off, before underlayment installation) is critical — the inspector walks the roof, checks for soft spots or rot, verifies nail patterns are pulled, and ensures deck is clean. This inspection often takes 30–60 minutes. If rot is found, the inspector may require documentation from a structural engineer before installation resumes, adding 1–2 weeks. The final inspection is typically faster (15–30 minutes) and confirms shingles are fastened correctly (nails visible in the right spot), flashing is sealed, and ridge vent is installed. Inspectors in Florissant are generally professional and knowledgeable; most roofers pass both inspections on the first visit if they follow IRC standards.
To avoid scheduling delays, confirm with your roofer that the roofer will call the Building Department the day before tear-off and will have a plan to start the project immediately if an inspection is approved for the following day. Some roofers are slow to call for inspections, thinking they can work without them and request a final inspection later — this is a code violation and may result in a stop-work order and re-inspection fees. Build the inspection calls into your project timeline: assume 2–3 weeks from permit issuance to final inspection approval, including weather delays and potential deck repair.
1 James J. Eustermann Drive, Florissant, MO 63031 (City Hall)
Phone: (314) 831-8666 (main) or (314) 831-8600 (Building Department direct — verify locally) | https://www.florissantmo.com/departments/building (check for online permit portal or submit in person)
Monday–Friday, 8:00 AM–5:00 PM (closed weekends and city holidays)
Common questions
My roofer says we can 'just overlay' my 3-layer roof without tearing off. Will Florissant allow this?
No. Florissant strictly enforces IRC R907.4, which prohibits a 4th layer. If your roof has 3 layers, a tear-off of all existing material is mandatory before installing new shingles. This is a common point of disagreement between roofers and homeowners — an overlay is cheaper, but the city will not issue a permit for one. Confirm the layer count with a field inspection before requesting a quote, and ask your roofer to get verbal approval from the Building Department if you're unsure whether an overlay is possible.
Do I need a permit if I'm just replacing a few missing shingles or patching a small area?
Patching fewer than 10 squares (1,000 square feet) of shingles, or repairs covering less than 25% of your total roof area, do not require a permit in Florissant. You can replace missing shingles or patch a damaged section without filing. However, if the patch involves flashing or underlayment replacement, or if the damaged area is larger than 25%, you cross into permit territory and must file. When in doubt, ask the Building Department — a 5-minute phone call can clarify whether your scope is a repair or a replacement.
What's the cost of a Florissant roofing permit?
Base permit fees for a residential roof replacement in Florissant are typically $150–$350, depending on roof area and complexity. A 2,500–3,500 square foot house (25–35 squares) would fall into the $150–$250 range for a like-for-like replacement. If a material change (asphalt to metal or tile) or structural review is required, the fee may be $250–$350. Inspection fees are usually included in the permit cost; you are not charged separately for each inspection visit.
Can I pull the roofing permit myself if I'm the homeowner?
Florissant allows owner-builder permits for owner-occupied single-family homes. Technically, you can pull the permit yourself by submitting the application to City Hall. However, most roofers pull the permit as part of their service, and it is simpler to let them handle it — they know the local requirements and can include the necessary documentation. If you are self-contracting the roofing work, you can pull the permit, but be prepared to provide roof area in squares, layer count, material type, and underlayment specifications.
What happens if the inspector finds rot or structural damage during the tear-off inspection?
If deck rot or structural damage is discovered during the tear-off inspection, the inspector will issue a written notice (stop-work order) and require you to hire a structural engineer to assess the damage and recommend repairs. The engineer's report must be submitted to the Building Department, and a revised permit (if repair costs exceed a threshold, typically $5,000) may be required. This adds 1–2 weeks to your timeline and $600–$1,500 in engineering cost, but it is necessary to ensure the roof and framing are safe. Rot repairs are common in older Florissant homes and are usually straightforward — the roofer and a carpenter handle the repair while the engineer verifies compliance.
Do I need special permits if I'm switching from asphalt shingles to metal or slate roofing?
A material change triggers additional scrutiny in Florissant. If switching to metal or slate, a structural engineer report is required to confirm that the existing roof framing can handle the fastening and load of the new material. Metal is typically lighter than asphalt, so most roofs pass easily, but the review is mandatory. Slate and tile are heavier and may require framing reinforcement, which adds significant cost and timeline. Plan for $600–$1,500 in structural engineering and 1–2 weeks of additional review time. Provide the engineer's report with the permit application to avoid delays.
How long does a roofing permit take from start to finish in Florissant?
A straightforward like-for-like replacement typically takes 5–7 business days from permit application to completion of the final inspection. Like-for-like means same material (asphalt to asphalt), one existing layer, no structural changes, and complete documentation. Material changes, structural issues, or incomplete permit applications add 1–3 weeks. The Building Department's office processes permits quickly, but inspection scheduling and weather can add time. Plan for 2–3 weeks as a realistic timeline to be safe.
Is ice-and-water shield required in Florissant, or is felt underlayment okay?
Florissant's building code requires ice-and-water shield in the eaves area extending at least 24 inches from the exterior wall line, per IRC R908.3. This is mandatory in Climate Zone 4A due to freeze-thaw cycles and ice dam risk. Felt underlayment alone is not sufficient for the eaves — it must be paired with ice-and-water shield. Your permit documents must specify ice-and-water shield type and installation area. The cost is about $150–$300 more than felt alone, but it is non-negotiable in Florissant.
Can I have my gutters replaced at the same time as my roof without an additional permit?
Gutter replacement alone does not require a permit in Florissant. However, if you are tearing off the roof, any gutter work (removal and reinstallation) is included in the roofing permit and inspected as part of the final inspection. The cost is bundled with the roofing project, and no separate permit is needed. Flashing work is also included in the roofing permit when done as part of a roof replacement.
What if the roofer I hired says they'll do the work without pulling a permit?
Do not allow this. Unpermitted roofing in Florissant can result in a stop-work order ($250–$500 fine), forced removal of the new roof, double permit fees, insurance claim denials, and resale disclosure issues (potential $5,000–$15,000 price reduction when selling). Florissant's inspectors and code enforcement are active, and neighbors can report unpermitted work. Always confirm in writing that your roofer will pull the permit and schedule inspections. If a roofer refuses to permit work, find a different roofer — a licensed roofer should welcome the permit process as proof of quality work.