COMMERCIAL
WATERPROOFING
IN HOUSTON, TX.
Houston publishes its flood exposure. City program guidance puts both the FEMA 100-year and 500-year floodplains inside the Special Flood Hazard Area, and the public flood-hazard map carries a dedicated 500-year layer for the 0.2-percent-annual-chance hazard. A commercial envelope on a screened parcel is therefore detailed against a known figure instead of a guess, and that figure reaches further up the building than owners expect: the foundation wall, the entrance threshold, the pit, and the deck draining toward all three.
What Commercial Waterproofing Includes
Scope here opens with a parcel-level look at Houston's flood-hazard mapping, and the enclosure work below is sized against what that screening turns up.
Elastomeric Coating Systems
A coating is the right answer when an elevation is cracked everywhere and nowhere in particular, and the wrong one when the cracking is structural or the wall is still wet. Griffin settles that first: crack pattern and whether it moves, spall repair, chalk and old coating removal, moisture read in the substrate. Film build, permeability, and adhesion are then proven on a test panel before an elevation is committed to one product.
Mid-century Houston hands a coating more than one substrate to cross. The city's landmark documentation lists steel beams, plate glass, slab doors, and metal window frames among the materials of local International Style buildings, whose low-rise examples carry flat roofs and horizontal window bands. Concrete is the finish on much of that generation and takes weather bare, the bands cut the wall into long runs, and the roof turns down into the top of them. We coat the field and detail those edges separately, because the edges are usually where it leaked.
Membrane Waterproofing
Membrane work buys back the surfaces nobody reaches twice: foundation walls, elevator pits, planters, and plaza or podium decks over occupied space. Griffin matches hot rubberized asphalt, fluid-applied, and sheet systems to the exposure and to whether water stands or runs, then draws every drain, curb, penetration, and termination. Those edges are where membranes fail, so they are resolved before a square-foot price means anything.
Below grade is where Houston's mapping stops being paperwork. City program guidance states that Houston Special Flood Hazard Areas include both the FEMA 100-year and 500-year floodplains under the city's Code of Ordinances. Which of those a parcel sits in decides whether a foundation wall is being detailed for damp soil or for standing head, and whether the elevator pit, the dock, and the ramp entrance belong in the same package. We settle it before the membrane is specified rather than after the excavation is open.
Sealant & Joint Replacement
A joint run is replaced end to end. Griffin takes out the failed material, cleans the substrate back to something a primer can bond to, sets backer at the depth the sealant needs to work, and picks the material for the movement the joint sees rather than the movement it was drawn for. Where a run meets a membrane, a flashing, or a termination bar, the overlap is drawn before it is caulked.
Opening a joint can turn a maintenance line into a permitted one. Houston's building-code modernization covered nine building codes, and its 2021 construction codes became effective January 1, 2024, which is the package a repair detail is measured against once an existing assembly is opened or altered. On a long run the question is usually what goes back: the same profile in the same place, or a changed geometry somebody has to draw. We sort the runs into those two columns while the quantities are still being counted.
Penetrating Masonry Sealers
Repellents are for walls that still have to breathe: brick, stone, and unglazed masonry where a film-forming product would hold moisture behind the face. Griffin measures absorption on the existing units, checks what earlier treatments left in the pores, and treats open head joints and cracks as work owed before any repellent is bought. Coverage is set by what the substrate drinks rather than by a rate on a data sheet.
Cleaning decides what a repellent has to work with. Houston's Heights design guidance puts low-pressure water washing first on historic materials, rules out abrasive methods, and asks that a mild chemical be proven in an inconspicuous spot before it goes across a wall. That matters to the waterproofing budget: an abrasive pass strips the hard outer surface off brick, absorption climbs, and a repellent priced for a sound face ends up covering a wall that now drinks faster. We clean to the gentlest method that works, then measure absorption again.
Industries We Serve in Houston
Houston Maps Its Flood Exposure, and an Envelope Scope Should Use the Map
Begin with the map, because Houston publishes one. The city's public flood-hazard map carries a dedicated FEMA 500-year floodplain layer representing the 0.2-percent-annual-chance flood hazard, and city program guidance folds that layer and the 100-year floodplain together into the Special Flood Hazard Area. Screening a parcel against both takes an afternoon and produces something a waterproofing scope can be argued from: a named exposure, tied to an address, that the owner, the engineer, and every bidder are reading the same way. Do it before a product is named, because the answer moves repairs between the maintenance column and the designed-detail column.
The two mapped lines then ask different things of the same building. A foundation wall detailed for damp soil and one detailed for standing head are not the same scope: positive-side membrane and drainage board where an excavation can be opened, an interior system where it cannot, and a pit that wants a sealed cover and a pump under either assumption. The same split runs up to grade, where a dock, a ramp, a door threshold, and a wall louver each sit at an elevation somebody once chose, and the mapping is what says whether that choice still holds. Carry both answers into the assessment and the scope comes back priced for the exposure the parcel has, not for the one the last capital plan assumed.
Houston's largest owners already budget the enclosure and the site together. In September 2026 the city approved $129.9 million in initial airport-system funding inside a seven-project, $229.9 million infrastructure program at George Bush Intercontinental Airport, and that program buys an 8,100-space employee parking lot, ecopark canopies, Terminal C pedestrian-bridge repairs, and expanded detention at Reinhardt Bayou, Garners Bayou, and Turkey Creek. Buildings, parking, walkways, and the basins taking their runoff sit in one authorization because on a campus they fail as one system. A smaller property has the same dependencies and less money, which argues for screening the whole site once and spending in the order that screening sets.
Houston's hazard areas start at this line, and it is the assumption most below-grade details were drawn against before anyone checked the wider one.
The city publishes this boundary as its own layer, so a parcel sitting between the two lines can be identified in an afternoon instead of disputed after excavation.
One airport program expands detention at three bayous while it repairs buildings and parking, which is what pairing site drainage with enclosure work looks like at scale.
Why Choose Griffin Restoration
Commercial exterior restoration since 2000
Licensed in TX, OK, AR, and LA
56' and 72' — self-performing capability
Full coverage for commercial projects
Commercial Waterproofing FAQ — Houston, TX
Our building sits outside the 100-year floodplain. Is it still in a mapped flood hazard area?
Houston draws that boundary wider than most owners check. City program guidance states that Houston Special Flood Hazard Areas include both the FEMA 100-year and 500-year floodplains under the city's Code of Ordinances, and the public flood-hazard map carries the 500-year boundary as a layer of its own for the 0.2-percent-annual-chance hazard. So a parcel can clear the line it has always been judged by and still be mapped. What that changes is the assumption underneath the below-grade details: how much head the foundation wall is being asked to take, where a pit pump and its alarm sit, and what elevation a loading dock, a threshold, or a wall louver was set at. We screen the parcel against both layers before a membrane or a drainage detail is selected, and the screening goes into the report so the next bidder argues from the same boundary.
Where does water get into a Houston commercial building that has never flooded?
At the top and at the joints, years before anything arrives at grade. Wind-driven rain works the horizontal breaks first: coping and parapet, the turn where a flat roof meets a wall, window-band heads and sills, and the perimeter of any glazing system. Houston's first aluminum curtain wall went up in 1956, and every glazing perimeter built since is a joint with a service life rather than a permanent seal. Inside the wall, water travels before it shows, so the stain on the fourth floor rarely sits under the defect that made it. Our investigation works upward from the lowest evidence and tests one variable at a time. Mapped flood exposure and ordinary envelope leakage are two different budgets, and running them together is how a property ends up with a new below-grade membrane and the same wet ceiling tile.
Does resealing or coating a designated Houston building need a Certificate of Appropriateness?
A resealing scope can trigger one, and the material decides it rather than the labor. The city's Certificate of Appropriateness requirement reaches exterior alterations on designated landmarks, protected landmarks, and properties within a city-designated historic district, while work that leaves an exterior feature's design, character, texture, and material as it found them stays on the maintenance side of the line. For waterproofing that usually comes down to three judgments: whether the new sealant reads the same color and profile as what was cut out, whether a repellent or coating changes how the wall looks wet or dry, and whether a failed unit is being replaced with a match. Houston allows administrative review where replacement material matches the historic material in size, shape, material, and pattern, which makes the dimensions and photographs taken during the assessment the thing that keeps the faster route open.
What happens when a wall is opened and the assembly is not what the drawings show?
The scope gets re-counted before the crew goes any further, and in Houston there is a code answer alongside the field one. The city's building-code modernization covered nine building codes and its 2021 construction codes became effective January 1, 2024, so a repair detail is checked against that package once an existing assembly is opened or altered. In practice the surprises are ordinary: a cavity packed with mortar droppings, flashing that stops short of the face, a through-wall detail that was never installed, an earlier repair done in a material nobody recorded. We carry investigation openings as their own line so the quantity behind them can move without a renegotiation, and anything found gets photographed in place with the assembly still open. A wall that has been opened once should not have to be opened again to answer a question the first opening could have settled.
We can only fund part of this. Which Houston waterproofing repairs should go first?
Start below grade and at the openings, then work upward. Those are the repairs that cost the most to reach a second time and the ones a mapped exposure speaks to directly, so they are worth doing while the excavation, the ramp closure, or the entrance shutdown is already paid for. Horizontal surfaces come next, because a deck or a plaza over occupied space turns a slow leak into interior damage faster than a wall does. Wall coatings and repellents are usually last, and they should be, since a coating applied over an unresolved joint or a saturated substrate buys a year. Houston's own large owners program this way: the September 2026 airport authorization put buildings, parking, canopies, and expanded stormwater detention into a single seven-project package rather than a queue of separate repairs. We write that order into the report with the reason for each step.
Serving Houston and the Gulf Coast — see all Houston & Gulf Coast service areas
Related Services
These services are commonly written into the same Houston scope as the waterproofing.
Commercial Facade Restoration
Open mortar joints, cracked units, and a failed glazing perimeter are entry points no membrane ever covers. On a Houston building where the mapped exposure is at grade and the stain is four floors up, the facade repair is what answers the second problem.
Review this service →Parking Garage Repair
A ramp, an entrance, and a bottom level are the parts of a Houston site that meet mapped water first. Deck joints, drains, and traffic coating are priced alongside the below-grade scope so the structure closes once.
Explore this service →Exterior Building Repair
Concrete that is spalling and embedded steel that is corroding keep moving under anything applied over them. Griffin repairs the substrate and waterproofs it under one scope, which is also the difference between one Houston mobilization and two.
Learn more →Protect Your Houston Property
We mobilize to Houston for commercial waterproofing on below-grade walls inside mapped flood hazard areas, on plaza and podium decks, and on mid-century concrete and glass buildings whose joints have outlived their sealant. Griffin Restoration Inc. puts the exposure, the details, and the order of the work into one document.