Skip to content
ARMORTHANE PROTECTING YOUR WORLD

PROTECTING YOUR WORLD

ARMORTHANE PROTECTING YOUR WORLD

Cool Deck Coating:
Cost, Heat &
What Lasts

How cool deck coating keeps pool decks cooler, what it costs in 2026, how long it takes to cure, and what to do when the slab underneath keeps cracking.
Pool Deck Quotes

Pool deck cracked or too hot? Get an honest recommendation.

Tell us the deck size, what it is surfaced with now and what is going wrong. A certified ArmorThane applicator near you will follow up.

  • Light, cooler deck colors
  • Slip-resistant textured finish
  • Flexible membrane over hairline cracks
  • UV-stable aliphatic topcoat
Rather talk now? Call (417) 831-5090
Step 1 of 3
$4–$6
Kool Deck, per sq ft installed
HomeGuide, 2026
10–25°F
Cooler slab when SRI rises from 35 to mid-50s
Solomon Colors
120°F+
Pavement hot enough to burn in minutes to seconds
NASA JPL, 2024
1962
Year Mortex introduced Kool Deck
Mortex

Cool deck coating is a light-colored, textured topping for concrete pool decks that keeps the surface cooler underfoot and less slippery when wet. The name comes from Kool Deck, a splashed-on concrete topping Mortex introduced in 1962, but today "cool deck" covers several products: the original cementitious topping, spray-and-knockdown acrylic overlays, deck paints and textured polymer systems. We make one of those, ArmorDeck, so we have a stake in this, but the honest truth is that color does most of the cooling work, and which system lasts depends mostly on the concrete underneath.

Quick answer

A cool deck coating works by reflecting more sunlight (light color, higher SRI) and breaking up the surface with texture. Raising a slab's solar reflectance index from standard gray (about 35) to the mid-50s keeps it roughly 10–25°F cooler in peak sun, according to Solomon Colors. Kool Deck runs about $4–$6 per sq ft installed (HomeGuide). It goes on new or sound concrete only; it cannot bridge moving cracks, so a cracked, hollow-sounding deck needs repair or a flexible membrane system instead.

What's in this guide
  1. 1What cool deck coating is, and why it is cooler
  2. 2Deck surface temperature estimator (tool)
  3. 3Cool deck vs. other pool deck surfaces
  4. 4Cool deck coating cost calculator (tool)
  5. 5Material and cure planner (tool)
  6. 6How cool deck is installed
  7. 7Cracking, peeling and repainting
  8. 8Cool deck coating FAQ
The basics

What is cool deck coating, and why is it cooler?

Plain concrete in full sun gets very hot. Solomon Colors notes concrete commonly runs 30–50°F hotter than the surrounding air, and cites a University of Nevada, Las Vegas measurement of pavement at 147°F on a 111°F day. The EPA reports conventional paving such as asphalt reaching up to 152°F at mid-day. NASA's ECOSTRESS mapping of Phoenix on June 19, 2024 found street surfaces of at least 120°F, hot enough to cause contact burns in minutes to seconds.

A cool deck coating lowers that number in two ways:

Main effect

Reflectance (color)

Solar reflectance index (SRI) measures how well a surface rejects solar heat. Standard gray concrete is about SRI 35 and asphalt can be near 0. Light tints reach the mid-50s to around 70. Solomon says going from 35 to the mid-50s keeps a slab about 10–25°F cooler under peak summer sun. This is why nearly every cool deck color is a pale buff, tan or white.

Secondary effect

Texture

The knobby, knocked-down texture means bare feet touch less surface area, and it gives grip when wet. It also hides foot traffic and stains. The trade-off is that deep texture traps dirt and needs a periodic scrub.

"Cool" is relativeNo coating makes a deck in direct Arizona sun feel like grass. A light cool deck is more comfortable than plain gray concrete and far more than dark pavers or stone, but on the hottest afternoons it can still be too hot for bare feet. Shade, misters and a quick rinse matter too.
Tool 1

How hot will your deck get? Surface temperature estimator

This estimator uses published rules of thumb for surfaces in peak direct sun, not a lab model. It is meant to show the size of the difference color makes, so you can compare a gray slab, a dark surface and a light cool deck on the same afternoon.

Estimator

Peak-sun deck temperature

Dark surfaces: air + 40–60°F (NASA JPL). Standard gray concrete, SRI about 35: air + 30–50°F (Solomon Colors). Light deck, SRI mid-50s: the gray-concrete range minus 10–25°F (Solomon Colors). Burn-risk flag at 120°F (NASA JPL).

—

Compare

Cool deck coating vs. other pool deck surfaces

Costs are installed, per square foot, from 2026 HomeGuide and Angi guides. Heat and slip ratings are our field experience; they depend heavily on the color you choose. Click a heading to sort.

SurfaceInstalled $/sq ftStays coolWet gripHandles slab movementUpkeep
Kool Deck / cementitious cool deck$4–$6Good (light colors)GoodPoor, cracks with slabRinse; repaint as it weathers
Basic concrete resurfacing$3–$6Depends on colorFairPoorSeal periodically
Decorative overlay (stain, texture)$6–$12Depends on colorFairPoorReseal every few years
Stamped overlay$7–$20Darker patterns run hotFair; add gritPoorReseal; add anti-slip
Pool deck paint$3–$8.50 (concrete $4–$8.50)Good if lightNeeds additivePoorAcrylic: recoat every couple of years
Epoxy pebble / rubber$4–$10FairGoodFairReseal; UV can yellow some epoxies
Polyurea / aliphatic deck system (ArmorDeck)QuoteGood in light colorsGood with aggregateElastomeric membraneClean; recoat topcoat when worn
Sources: HomeGuide pool deck resurfacing cost (2026); Angi cost to paint a pool deck. ArmorDeck pricing varies by applicator and region, so we do not publish one.
Tool 2

Cool deck coating cost for your pool deck

HomeGuide puts a typical 500–900 sq ft pool deck at $1,500–$10,800 to resurface, depending on the system. Enter your deck size and the calculator prices every option side by side with the same 2026 per-square-foot ranges used in the table.

Calculator

Pool deck surface cost comparison

Total = area × low and high installed price per sq ft. Bars show each option's midpoint so you can see the spread at a glance. Add a repair allowance for cracks or lifted sections.

Pool-surround area only, not the water
From your contractor's walk-through
—
Selected option, total
—
Midpoint
—
Cheapest option range

Tool 3

Cool deck material and cure planner

For the original Kool Deck topping, Mortex's installation instructions say a properly mixed unit covers a minimum of 300 sq ft, the finished surface should be no more than 1/8 in. thick, it goes on in two splashed coats, and the deck needs about 21 days before general use. If you are planning a build or a pool party, that last number matters.

Planner

Kool Deck units and ready date

Units = area ÷ 300 sq ft (Mortex minimum coverage), rounded up, plus your spare allowance. Ready date = application date + 21 days (Mortex).

Covers waste and touch-ups
—
Units to order
—
Ready for general use
—
Days of buffer

Installation

How cool deck coating is installed

  1. Start with sound concrete

    The original Kool Deck instructions are written for freshly poured slabs. On an existing deck, cracks, hollow spots and lifted sections have to be repaired, and old coatings removed, or the new topping fails where the old one did.

  2. Protect the pool and coping

    Mask tile, coping, drains and the waterline. Cementitious splatter is hard to remove from tile once it sets.

  3. Splash on two coats

    Mortex describes splashing the mix on in even, straight, side-by-side rows with a flick of the wrist, in two coats, keeping the total at or under 1/8 in.

  4. Knock down the texture

    Once the splatter firms, a trowel flattens the tops of the peaks to the knockdown pattern people recognize. Timing decides how sharp or smooth the finish feels underfoot.

  5. Cure before use

    Mortex calls for about 21 days before general use. Keep furniture off and avoid heavy hosing during that period.

  6. Paint or seal as it weathers

    Mortex says Kool Deck on fresh concrete contains its own sealer and curing agents, so it needs no further work at install. Over the years most decks get an acrylic deck paint to refresh color; plan on recoats every couple of years if you go the acrylic route (Angi).

Troubleshooting

Cool deck cracking, peeling and when to start over

Most common

Cracks that come back

A thin cementitious topping moves with the slab beneath it. When the slab cracks at a control joint or settles, the cool deck cracks right above it. Patching the topping without dealing with the movement just relocates the crack. Saw-cut and flex-seal control joints, or use an elastomeric system that can stretch.

Paint layers

Peeling paint on old cool deck

Repeated coats of deck paint eventually lose adhesion, especially where water sits. Pressure-wash, scrape to sound material and use a primer the paint maker approves for cementitious decks. If several coats are lifting, stripping beats another layer.

Start over

Hollow-sounding, delaminating areas

Tap with a hammer handle. Large hollow areas mean the topping has let go of the slab. That section needs removal and a full resurfacing, not paint.

Safety

Slippery or slimy spots

Algae and sunscreen build-up fill the texture. Scrub with soap and water, as Mortex recommends. If a painted deck is slick, add a fine grit to the next coat; see our anti slip paint guide.

Where an ArmorDeck system fits

We built ArmorDeck for decks that keep cracking. The basecoat is a high-solids, solvent-free, moisture-cured aromatic urethane polyurea elastomeric waterproofing membrane for concrete and plywood decks, patios and walkways; the topcoat is an aliphatic urethane polyurea for UV and abrasion resistance and must go on within 48 hours of the base. In light colors with slip-resistant aggregate it gives you the cool, grippy surface of a cool deck plus a membrane that stretches over hairline slab movement and keeps water out of the slab. It is more expensive than a cementitious topping and needs a trained applicator. If your slab is sound and you just want a cooler, classic look, a cool deck topping is a perfectly good choice.

For a wider look at options, see our pool deck resurfacing page and the pool deck resurfacing guide. Painting the pool itself is a separate job covered in our pool paint guide. Pavers around the pool are a different animal again; see paver sealer.

Tired of patching cracks?

A cool, textured pool deck that flexes with the slab.

Certified ArmorThane applicators install ArmorDeck and textured polyurea systems on pool decks, patios and walkways. Send us a few photos and the deck size and we will tell you honestly whether a cool deck topping or a membrane system fits better.

Get a free quoteFind an applicator

Contractors: become an applicator →

FAQ

Cool deck coating questions

What is cool deck coating made of?

The original Kool Deck is a cement-based topping that is splashed on and troweled into a knockdown texture. Many modern cool decks are acrylic-modified cement overlays, and some are textured polymer coatings. What they share is a light color and a textured surface.

How much cooler is a cool deck than concrete?

It depends mostly on color. Solomon Colors estimates that raising a slab's SRI from standard gray (about 35) to the mid-50s keeps it about 10–25°F cooler in peak summer sun. The EPA reports cool pavements staying 10 to 16°F cooler than conventional ones in a field study.

How much does cool deck coating cost?

HomeGuide's 2026 range for Kool Deck is $4 to $6 per square foot installed. A 700 sq ft deck therefore runs roughly $2,800 to $4,200 before any crack repair or removal of old coatings.

Can you put cool deck over existing concrete?

Yes, if the concrete is sound, clean and free of coatings that would block the bond. Mortex's instructions are written for fresh slabs, so on older decks follow the installer's prep and bonding procedure, and repair cracks and hollow areas first.

How long does cool deck take to cure?

Mortex calls for approximately 21 days before the deck is ready for general use. Plan installs at least three weeks ahead of the pool season or any event.

Why is my cool deck cracking?

Because the slab underneath is. A thin topping cannot hold a crack closed if the concrete moves. Treat the cause with proper control joints, settlement repair or a flexible membrane system, then resurface.

Can I paint over cool deck?

Yes. Clean thoroughly, let it dry, and use a deck paint rated for cementitious pool decks in a light color to keep the cooling effect. Add a fine anti-slip additive to the final coat if it will be wet often. Expect to recoat acrylic paints every couple of years.

Is cool deck slippery when wet?

An unpainted knockdown texture has good grip. Smooth paint coats and algae can make it slick over time, so keep it clean and add grit when repainting.

AT
Written by the ArmorThane technical team. We have manufactured polyurea, polyurethane and polyaspartic coatings in Springfield, Missouri since 1989, including the ArmorDeck system, and train certified applicators across North America. Figures come from the sources listed below. Updated October 2026.

Sources

  1. HomeGuide, pool deck resurfacing cost (2026): homeguide.com/costs/pool-deck-resurfacing-cost
  2. Angi, cost to paint a pool deck: angi.com/articles/cost-to-paint-pool-deck.htm
  3. Mortex, Kool Deck installation instructions: mortex.com/pdf/KoolDeckInstructions.pdf
  4. Mortex, Kool Deck consumer brochure: mortex.com/pdf/KoolDeck-Consumer.pdf
  5. Solomon Colors, How to Keep Concrete Cool with Smart Color Choices: solomoncolors.com/blog/cool-concrete.html
  6. U.S. EPA, Using Cool Pavements to Reduce Heat Islands: epa.gov/heatislands/using-cool-pavements-reduce-heat-islands
  7. NASA JPL, ECOSTRESS maps burn risk across Phoenix streets (2024): jpl.nasa.gov/images/pia25529...

latest news & bLOGS

Learn more

A cooler pool deck that stays put.

Homeowners get a certified ArmorThane applicator for pool decks, patios and walkways. Contractors can add ArmorDeck and polyurea deck systems with no franchise fee and no royalties.

Find an applicator →Become an applicator
United States 417-831-5090 · Canada 780-444-6200

CONTACT US

REQUEST A QUOTE OR

BECOME AN APPLICATOR

ArmorThane has built a strong reputation over the past 30 years for producing high-quality, durable protective coatings.

group 115 660555abebfe4
Phone Number

Tel: 417.831.5090

group 115 1 660556c21395c
Email Us

moreinfo@armorthane.com

Step 1 of 3

We want to help you find the best ArmorThane applicator for your protective coating project. Please either fill out the request form below or call us toll free at 417-831-5090, any time Monday-Friday, 8:00 a.m. to 5:00 p.m. Central Standard Time.

RV Find An Applicator

Step 1 of 3

Connect with an authorized ArmorThane professional to get a long-lasting, seamless protective coating for your RV. Submit the form below or call us directly at 417-831-5090 (Monday–Friday, 8:00 AM – 5:00 PM CST).

Facebook Twitter Youtube

Find An Applicator

Applicator Login

Armorthane Logo Outlined
CALL NOW
BECOME APPLICATOR
FIND APPLICATOR

Protective Coating Applications

Products

Applicator Opportunities

Knowledge Center

Galleries