By The Roofing Brief Team. Last reviewed: October 2026.
Roof coating types come down to four major chemistries, silicone, acrylic, polyurethane and asphalt emulsion, and to compare roof coatings you match each one to ponding water, UV exposure, foot traffic, climate and the substrate being coated. Choose by chemistry first and price second, because a coating that fails on the wrong roof can bring a reroof forward. HomeGuide’s roof coating cost guide (April 2024) puts installed prices at $0.50 to $3.00 per square foot for acrylic, $1.00 to $2.50 for bitumen, $1.50 to $4.00 for polyurethane and $1.50 to $4.50 for silicone; for line-item pricing, prep costs and warranty tiers, see our guide to commercial roof coating cost per square foot.
Restoring an aging single-ply or modified bitumen flat roof? See our flat roof coating restoration guide and our 2026 commercial roof restoration cost guide.
Compare roof coatings: specification chart by product
The chart compares named products on the numbers their technical data sheets publish: chemistry, the ASTM product standard, solids by volume, application rate, dry film thickness, solar reflectance and the application temperature window. Blank cells mean the cited sheet does not state the value.
| Product | Chemistry | Standard | Solids by volume | Rate per 100 sq ft | Dry film | Solar reflectance | Apply at | Source |
|---|---|---|---|---|---|---|---|---|
| Henry 887 Tropi-Cool | Silicone, moisture-cure | Meets ASTM D6694 | 91% (plus or minus 3) | 1.5 gal | 22 mils min | 0.88 initial, 0.73 aged (CRRC 0620-0051) | 35°F to 120°F | Henry TDS, rev. 5/2022 |
| Rust-Oleum 995 | Silicone | 95.5% | 1.5 gal (25 wet mils) | 24 mils | 0.87 initial | 32°F to 120°F | Rust-Oleum TDS | |
| GacoFlex S20 Series | Silicone, moisture-cure | 1.5 gal smooth, 2 gal granulated | About 22 mils (smooth) | Gaco S20 data sheet | ||||
| Henry 587 Dura-Brite | Acrylic elastomeric | 47% to 51% | About 1 gal in two coats | About 7.5 to 8.2 mils (calculated) | 0.84 | 50°F and rising | Henry TDS, rev. 5/2015 | |
| Conklin Rapid Roof III | Acrylic elastomeric | 1.9 gal | About 13.5 mils per coat | 85% initial | Conklin specification sheet | |||
| APOC 247 Sun-Shield | Acrylic | 3 gal total (2 coats of 1.5) | APOC TDS | |||||
| Henry 107 | Asphalt emulsion, non-fibered | Exceeds ASTM D1227 Type III, Class I | 40% to 50% | 3 to 4 gal, one coat | Black | 50°F and rising | Henry TDS, rev. 8/2015 | |
| Polyurethane systems | Aromatic base, aliphatic top | ASTM D6947 (moisture-cured) | Per system spec | Per system spec | ASTM D6947 |
Roof coating formulas: mils, gallons and coverage
Three equations do most of the work when you compare roof coating bids. One US gallon is 231 cubic inches, so spread over 100 square feet (14,400 square inches) it lays down 0.01604 inch, or about 16 wet mils. Dry film is wet film times solids by volume.
- Wet mils = gallons per 100 sq ft x 16.04. At 1.5 gallons that is 24 wet mils; at 2 gallons, 32.
- Dry mils = wet mils x solids by volume. Henry 887 at 1.5 gallons: 24 mils x 0.91 = about 22 mils dry, the minimum Henry prints. Henry 587 at 1 gallon: 16 mils x 0.47 to 0.51 = about 7.5 to 8.2 mils dry.
- Gallons to order = roof area / 100 x rate, plus loss. Rust-Oleum’s practical coverage for 995 (65 sq ft per gallon) already assumes 15% material loss, so a 10,000 sq ft roof needs about 154 gallons at that figure.
The Uniflex silicone spec for structural metal follows the same math: 1.5 gallons per 100 sq ft is 24 wet and 22 dry mils for its 10-year warranty, and 2 gallons is 32 wet and 30 dry mils for 15 years. When two bids quote the same chemistry, ask each for gallons per 100 sq ft and solids by volume, then run line 2.
Silicone roof coatings: the ponding-water choice
Silicone is the premium roof coating chemistry in 2026 and the usual spec for flat roofs where water ponds. Conklin’s acrylic data sheet treats more than 36 square feet of water a quarter inch deep 48 hours after rain as unacceptable for coating, and silicone is the chemistry makers rate for that condition: Henry describes its 887 Tropi-Cool silicone as providing permanent ponding water resistance, and Rust-Oleum lists ponding resistance for 995.
Our silicone roof coating guide goes deeper on the chemistry. The silicon-oxygen backbone is what makers credit for the water resistance; Henry rates 887 at less than 0.001% water absorption (ASTM D471).
The major silicone brands in 2026:
GacoFlex S20 Series (S2000 is the white color): a solvent-free, single-component, moisture-curing silicone. Gaco’s S20 Series data sheet lists 1.5 gallons per 100 square feet for about 22 dry mils on smooth surfaces and 2 gallons per 100 square feet on granulated surfaces. Gaco states that all GacoFlex silicone roof coatings carry a 50 year limited material warranty. That warranty covers the product, not the roof system: a labor and material warranty is available only through Gaco licensed applicators, over Gaco’s E5320 primer and to Gaco specifications, and its term follows the system spec, for example 15 years at 30 dry mils in Gaco’s MR-S20-30-15 metal roof specification.
Henry 887 Tropi-Cool: a 100 percent silicone, moisture-cure white roof coating that Henry markets for low-slope and pitched roofs in hot, wet climates. Its data sheet lists 1.5 gallons per 100 square feet in one coat, about 320 square feet per 5-gallon container, and rain-safe in 15 minutes. We break down Henry roof coating prices per 100 sq ft in our Henry roof coating prices per 100 sq ft review.
Silicone application requires the substrate to be clean and dry. The coating cures by absorbing atmospheric moisture, so timing matters: Rust-Oleum says not to apply 995 if rain is expected within 2 hours, while Henry rates 887 rain-safe in 15 minutes. The cured silicone surface is slippery when wet; Uniflex’s spec adds granular walkways at 25 pounds of granules per 100 square feet over an extra gallon per square.
Silicone fits flat roofs with ponding water that does not drain within 48 hours, single-ply membranes (TPO, EPDM, PVC) that are still serviceable but need life extension, and metal roofs with surface rust that has not penetrated the panel. Both Henry 887 and Rust-Oleum 995 list aged TPO, EPDM, PVC and metal as substrates. See our elastomeric roof coating guide for the broader elastomeric framework.
Acrylic roof coatings: the well-drained-roof choice
Acrylic is a widely used roof coating chemistry and a common spec for budget restoration work on roofs that drain well. It is water-based, which makes application clean and low-VOC, and it is covered by its own product standard, ASTM D6083. HomeGuide prices acrylic at $0.50 to $3.00 per square foot installed, the lowest of the four chemistries at the bottom of the range.
The major acrylic brands in 2026:
APOC 247 Energy-Armor Sun-Shield: APOC’s technical data sheet describes it as a flexible, white acrylic roof coating applied in two coats at 1.5 gallons per 100 square feet each, for a total of 3 gallons per 100 square feet. The data sheet states a one year product warranty from purchase, with extended terms available by registration. It is an acrylic, not a polyurethane or a silicone.
Conklin Rapid Roof III: an elastomeric acrylic coating sold through Conklin’s distributor network. Conklin’s specification data sheet lists an acrylic resin, 1.9 gallons per 100 square feet, about 13.5 dry mils per coat and 85 percent initial reflectivity, and the product page cites 40 years of service history. The same data sheet treats more than 36 square feet of water a quarter inch deep 48 hours after rain as an unacceptable surface for coating.
Acrylic application is forgiving in the hand: the water-based formulation cleans up with water and sprays through standard airless equipment. The weather window is the constraint. Henry’s 587 data sheet says not to apply if rain, dew or temperatures below 50°F are expected within 48 to 72 hours, and acrylic makers such as Conklin set explicit ponding limits. For a side-by-side on the two most common chemistries, see our silicone vs acrylic roof coating comparison.
Acrylic fits flat roofs with positive drainage (no more than Conklin’s 36 sq ft of quarter-inch ponding at 48 hours), sloped metal roofs with rust that needs UV protection, RV and camper roofs that need resealing, modified bitumen roofs that need a reflective topcoat, and budget restorations on buildings with a short remaining hold period.
Polyurethane roof coatings: the foot-traffic choice
Polyurethane is the abrasion-resistant choice among the four major roof coating chemistries. The cured surface resists foot traffic and mechanical wear better than silicone or acrylic, which is why it is specified on roofs with frequent rooftop equipment service and deck-style amenity roofs. HomeGuide prices polyurethane (polyurea) coatings at $1.50 to $4.00 per square foot installed.
Polyurethane comes in two formulations: aliphatic (UV-stable, used as the topcoat) and aromatic (faster-curing, used as the basecoat). Most polyurethane systems are two-coat installations with an aromatic basecoat for adhesion and waterproofing followed by an aliphatic topcoat for UV stability. Moisture-cured polyurethane coatings are covered by ASTM D6947, written for spray polyurethane foam roofs.
Polyurethane systems are sold by several coating and membrane manufacturers, each with its own base coat, top coat and thickness requirements, so compare the system specification rather than the product name. One common mix-up: APOC 247 is an acrylic, not a polyurethane.
Polyurethane application is the most technique-sensitive of the four chemistries. Moisture-cured products are covered by ASTM D6947. Ask the bidder for the system’s base and top coat products, the dry mils for each, the primer on porous substrates, and how occupants and air intakes will be protected from solvent odor; Uniflex’s silicone spec, for comparison, requires the owner to be told start times so fresh-air intakes can be closed.
Polyurethane systems built to ASTM D6947 fit amenity decks and high-traffic rooftops, parking deck waterproofing, single-ply membranes that need life extension under heavy mechanical wear, and any roof where abrasion is the spec driver. Our polyurethane roof coating guide breaks down the aliphatic and aromatic formulations in more detail.
Asphalt emulsion roof coatings: the BUR and mod-bit choice
Asphalt emulsion is the oldest of the major roof coating chemistries and the lowest-cost option for asphalt substrates. It is water-based asphalt (asphalt particles dispersed in water with emulsifiers) that cures by water evaporation to a black, flexible, waterproof film, and it is covered by ASTM D1227. It is the spec on built-up roofing (BUR) restoration, modified bitumen seal coats, and budget restoration of asphalt-based roofs. Our guide to roofing emulsion covers fibered versus non-fibered grades and the roofs where it is the wrong choice.
A widely stocked example is Henry 107 Asphalt Emulsion: its 2015 data sheet lists 3 to 4 gallons per 100 square feet in one coat, 40 to 50% solids by volume, application at 50°F and rising, and compliance with ASTM D1227 Type III, Class I.
Asphalt emulsion application is straightforward: it sprays or rolls easily and cleans up with water. The cured film is black, so it absorbs solar heat, the opposite of the cool-roof effect of a white coating such as Henry 887 (0.88 initial solar reflectance). On roofs where a reflective surface is wanted or required, emulsion is typically topped with a reflective coating or replaced by a white silicone or acrylic system; Henry’s 587 acrylic sheet lists asphalt emulsion as a direct substrate once it has cured, normally 1 to 7 days.
Asphalt emulsion fits BUR restoration where the existing membrane is still serviceable, modified bitumen seal coats where cap sheet granules have weathered, budget restoration of asphalt-substrate roofs, and cold-climate roofs where a dark surface is acceptable. HomeGuide prices bitumen coatings at $1.00 to $2.50 per square foot installed.
The four major roof coating chemistries at a glance, with installed ranges from HomeGuide (April 2024). Our commercial roof coating cost breakdown covers prep line items and warranty tiers:
| Coating type | Best use | Installed cost per square foot | Source |
|---|---|---|---|
| Silicone | Flat roofs with ponding water, single-ply and metal roof life extension | $1.50 to $4.50 | HomeGuide |
| Acrylic | Well-drained roofs, reflective cool-roof topcoats, budget restorations | $0.50 to $3.00 | HomeGuide |
| Polyurethane | High-traffic and mechanical-wear roofs, amenity decks, parking decks | $1.50 to $4.00 | HomeGuide (polyurethane / polyurea) |
| Asphalt emulsion | Built-up roofing and modified bitumen restoration, cold-climate roofs | $1.00 to $2.50 | HomeGuide (bitumen) |
| Warranted silicone system, 10,000+ sq ft | 10 to 15 year warranted restoration | $2.80 to $4.00 | Custom Coatings Inc. |
| If your roof has | Choose | Threshold or source |
|---|---|---|
| Ponding: over 36 sq ft of water 1/4 in deep 48 hours after rain | Silicone, or fix drainage first | Conklin acrylic data sheet limit; Henry 887 rated for permanent ponding |
| Positive drainage, budget first | Acrylic | HomeGuide $0.50 to $3.00 per sq ft |
| Frequent foot traffic or equipment service | Polyurethane, or silicone with granular walkways | Uniflex walkway: 25 lb granules per 100 sq ft |
| Serviceable BUR or mod-bit, black surface acceptable | Asphalt emulsion | Henry 107: 3 to 4 gal per 100 sq ft |
| White coating over asphalt | Bleed-blocking primer first | Rust-Oleum 130 primer under 995 |
| Temperatures under 50°F expected within 72 hours | Silicone, not acrylic | Henry 587 limit; Henry 887 applies down to 35°F |
| Roof already silicone-coated | Silicone only | Rust-Oleum lists existing silicone as a 995 substrate; Henry 887 warranty void under non-approved products |
| Want a 15-year system warranty | About 30 dry mils of silicone by an approved applicator | Uniflex 2 gal per 100 sq ft; Gaco MR-S20-30-15 |
| Wet insulation or active leaks | Moisture survey, repair or reroof first | Coatings need a dry, sound substrate |
Climate fit: matching coating chemistry to climate zone
Matching roof coating chemistry to climate comes down to three measurable things: UV dose, rain and humidity during the cure, and the temperature window on the data sheet. High-UV regions favor reflective silicone and white acrylic, rainy and humid regions favor silicone’s fast moisture cure (Henry 887 is rain-safe in 15 minutes), and cold shoulder seasons rule out coatings that need 50°F and rising, such as Henry 587 acrylic and Henry 107 emulsion.
Sun Belt and high-UV climates (Florida, Texas, Arizona, Southern California, Nevada): silicone and white-pigmented acrylic fit, because reflectance is the payoff: Henry 887 holds 0.73 solar reflectance after aging in its CRRC rating and Henry 587 lists 0.84 initial. A black asphalt emulsion surface gives up that cooling effect unless it is topped with a reflective coat.
Cold-climate Northeast and Midwest: the coating decision is more flexible, and the spec is driven by the roof (ponding water drives silicone, foot traffic drives polyurethane, budget drives acrylic or asphalt emulsion). The calendar matters more: Henry 587 needs no rain, dew or sub-50°F temperatures for 48 to 72 hours after application, while Henry 887 applies from 35°F.
Coastal and high-humidity climates (Gulf Coast, Pacific Northwest, Southeast): silicone fits because of its ponding resistance and moisture-cure chemistry, which uses humidity rather than fighting it. Acrylic works on properly drained roofs when the 48 to 72 hour dry window can be met. For flat commercial roofs specifically, our best roof coating for a flat roof guide narrows the choice.
High-altitude and mountain climates (Colorado, Utah, Wyoming, Montana): the UV exposure is severe (UV levels rise roughly 10 percent with every 1,000 meters, about 3,300 feet, of altitude, per the World Health Organization), which pushes many specifiers toward silicone or polyurethane and shortens the recoat interval for UV-sensitive coatings.
Application method: spray, roll, or brush
The application method is largely a function of roof geometry and crew preference, not coating chemistry. All four major chemistries can be sprayed through airless equipment, rolled, or brushed in detail areas, but the equipment spec differs by product, from a 3/4-inch nap roller to spray rigs rated 5,000 psi or more.
Airless spray application: the fastest method on large open roofs. Silicone needs high pressure: Henry’s 887 sheet calls for a commercial airless rig producing at least 3,500 psi at the gun tip with a 3 gallon per minute pump, Uniflex recommends 5,000 psi at the tip with a .031 to .035 inch tip, and Rust-Oleum specifies a pump rated for at least 5,950 psi for 995.
Roller application: the slower method, used on smaller roofs and on detail work around penetrations. Uniflex and Rust-Oleum both call for at least a 3/4-inch nap roller, and a wet mil gauge checks film thickness as you go.
Brush application: reserved for detail work around penetrations, seams, drains, and edges. Brushing is also the standard for the first detail coat over polyester reinforcing fabric; Uniflex specifies sealant 1/16 inch thick (60 wet mils) extending 3 inches around curbs and penetrations.
Reinforcement: where polyester fabric goes in
Most coating systems include polyester reinforcing fabric in seams, penetrations, and high-stress detail areas, priced below from Custom Coatings Inc. figures. The fabric is embedded in the first coat, smoothed to remove bubbles, and over-coated with the later coats. The reinforcement adds tensile strength at the most failure-prone areas: where two membrane sheets meet, where a pipe boot transitions to the membrane, and where the membrane terminates at edge metal.
Reinforcement is priced either per square foot or per foot of seam. Custom Coatings Inc. publishes $1.00 to $2.00 per square foot for full-coverage fabric reinforcement and $2.25 to $4.45 per linear foot for seam-only reinforcement on roofs of 10,000 square feet or more. Skipping fabric in detail areas leaves the seams, where the coating film is under the most stress, carrying unreinforced coating. Which coating bonds to which substrate is a separate spec question, covered in our roof coating materials guide.
Lifespan and warranty by chemistry
Roof coating life tracks chemistry and dry film thickness, and the published warranty is the most checkable proxy for it. Uniflex, for example, ties 10 versus 15 years of coverage to 22 versus 30 mils dry. Warranty type matters as much as term: a long product warranty is not the same as a system warranty.
Silicone: Uniflex issues a 10-year warranty at 1.5 gallons per 100 square feet (22 dry mils) and 15 years at 2 gallons (30 dry mils) over structural metal. Gaco’s system term follows its spec, for example 15 years at 30 dry mils, while its 50 year term is a limited material warranty on the product. Henry 887 carries a lifetime limited product warranty that is void if the roof is later coated with a non-approved product.
Polyurethane: terms follow each maker’s two-coat system spec and dry mils; get the base and top coat thickness in writing with the warranty.
Acrylic: APOC 247 carries a one year product warranty from purchase, extended by registration. Acrylic systems on roofs that pond beyond Conklin’s 36 sq ft at 48 hours limit fall outside the maker’s acceptable surface.
Asphalt emulsion: Henry 107 is sold as a sealer meeting ASTM D1227 Type III, Class I; check the current Henry sheet for its warranty terms before relying on it as a long-term surface.
Read the warranty type before the term: material-only, labor and material, and NDL warranties pay for very different things. Market lifespan figures by material are in our 2026 Roofing Material Lifespan Report.
When coating restoration beats reroof: the cost math
A coating restoration usually costs a fraction of a reroof: Custom Coatings Inc. quotes $2.80 to $4.00 per square foot for a 10 to 15 year warranted coating system on a 10,000 square foot or larger roof, against $5.00 to $11.00 for a new membrane with full tear-off. On a 10,000 sq ft roof that is $28,000 to $40,000 to coat against $50,000 to $110,000 to replace. Our commercial roof coating cost guide runs the coat, recover and reroof math.
The case for coating is strongest when the existing membrane is watertight, the deck is dry, the insulation is intact, and the owner’s hold period is within the 10 to 15 year warranty a coating system can carry. If the membrane has active leaks, the deck has moisture intrusion or the insulation is wet, a reroof or repair comes first. A moisture survey, such as an infrared scan to ASTM C1153, capacitance readings or core samples, confirms the substrate before the coating decision is final.
Our commercial roof restoration overview walks through the full restoration vs replacement decision tree, and the broader cost framework is in our 2026 Roofing Cost Report. For industrial flat roofs, pair this guide with our industrial roof repairs cost piece.
Frequently asked questions about roof coatings
Which roof coating lasts the longest?
Silicone carries the longest system warranties among the products cited here: Uniflex issues 15 years at 2 gallons per 100 square feet (30 dry mils), and Gaco offers 15 years at 30 dry mils through licensed applicators. Gaco’s 50 year term is a limited material warranty on the product, not a system warranty. Coating life tracks dry film thickness, so compare mils, not brand names.
How much does roof coating cost per square foot?
HomeGuide (April 2024) puts installed roof coating at $0.50 to $3.00 per square foot for acrylic, $1.00 to $2.50 for bitumen, $1.50 to $4.00 for polyurethane and $1.50 to $4.50 for silicone. Custom Coatings Inc. quotes $2.80 to $4.00 for a warranted system on roofs of 10,000 square feet or more, plus $1.00 to $2.00 per square foot for full fabric reinforcement.
What is the best roof coating for ponding water?
Silicone is the best roof coating for ponding water. Henry rates its 887 silicone for permanent ponding water resistance with under 0.001% water absorption, while Conklin’s acrylic data sheet treats more than 36 square feet of water a quarter inch deep 48 hours after rain as unacceptable for coating.
Is roof coating cheaper than a full reroof?
Usually. Custom Coatings Inc. quotes $2.80 to $4.00 per square foot for a warranted coating system on a 10,000 square foot or larger roof, versus $5.00 to $11.00 for a new membrane with full tear-off. Coating makes sense when the membrane is watertight, the deck and insulation are dry, and the hold period fits a 10 to 15 year coating warranty. A moisture survey confirms the substrate first.
Do roof coatings need reinforcement fabric?
Most coating systems use polyester reinforcing fabric in seams, penetrations and high-stress detail areas. The fabric is embedded in the first coat and over-coated with later coats, adding tensile strength where two membrane sheets meet or a pipe boot transitions to the membrane. Custom Coatings Inc. prices seam-only reinforcement at $2.25 to $4.45 per linear foot on larger roofs.
Which roof coating is best for hot, sunny climates?
Silicone and white-pigmented acrylic fit Sun Belt and high-UV climates such as Florida, Texas, Arizona and Nevada because both reflect solar heat. Henry 887 silicone holds 0.73 solar reflectance after aging in its CRRC rating, and Henry 587 acrylic lists 0.84 initial. Black asphalt emulsion absorbs heat unless topped with a reflective coat.