What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Not reliably from a household recipe. Purdue’s ultra-white cooling paint is a research formulation of barium sulfate (BaSO4) particles in an acrylic matrix. The published work reports impressive cooling performance for that engineered composite, but it does not provide a validated DIY recipe showing that ordinary barium sulfate powder mixed into ordinary paint will perform the same way.
How the paint is designed to cool
The coating uses passive daytime radiative cooling: it reflects much of the sunlight that would otherwise heat a surface, while emitting thermal energy through a part of the atmosphere known as the sky window. High solar reflectance helps limit heat gain, but reflectance alone does not prove that a coating will cool below the surrounding air temperature; thermal emission and test conditions matter too.
As an Amazon Associate I earn from qualifying purchases.
In the 2021 study, Li, Peoples, Yao and Ruan report that their BaSO4-acrylic paint had 98.1% solar reflectance and 0.95 sky-window emissivity. The researchers designed it as a single-layer composite, using a high concentration of particles with a deliberately broad size distribution to scatter sunlight across a wide range of wavelengths. Read the study abstract from Purdue’s Cooling Technologies Research Center or the full paper hosted by Purdue.
What is in the published formulation?
The paper reports a 60% volume concentration of BaSO4 in the acrylic paint. Purdue’s account says the selected average particle size was around 400 nm. Those are research parameters, not a complete household formula: the sources do not establish that matching those two figures alone would reproduce the coating’s optical properties or cooling results.
#1 Best Overall
- ELASTOMERIC ROOF SEALANT: Seal and protect your roof from intense heat and harsh UV rays with Gardner-Gibson Sta-Kool 15-Year Turbo-Dri Elastomeric Roof Coating. It's engineered to be "rain safe" in 30 minutes for protection against unexpected rain.
- COOL-CORE TECHNOLOGY: This heat reflective paint features "cool-core" technology – specialized pigments that repel heat gain to keep interiors cooler and help save on cooling costs.
- PREMIUM “SINGLE DAY” WHITE ROOF COATING: Engineered to be “Rain Safe” in 30 minutes and recoated in just three hours, STA-KOOL Turbo-Dri Technology greatly improves efficiency allowing for faster completion times and unprecedented protection against unexpected rain.
- EASY TO APPLY: Simply use a roller to spread Sta-Kool into a uniform coat on your surface. Follow all directions on label. Packaged in a 5-gallon container.
- SERVING PROS SINCE 1945: Established in 1945, Gardner-Gibson has been setting the industry standard with a variety of roof, road and waterproofing products for more than 75 years.
Particle size distribution and the way the particles are incorporated into the acrylic matrix are central to the reported design. Simply adding a bag of barium sulfate to a can of white paint is not an evidence-backed equivalent to the tested composite.
Can you make it yourself?
You can understand the key ingredients and design aims, but the reviewed publications do not supply a validated consumer recipe, mixing procedure, application specification or DIY performance test. They therefore do not support instructions or promised results for a home-made batch. Purdue describes the technique as compatible with commercial paint fabrication, which is different from confirming that a consumer can reproduce the laboratory formulation with off-the-shelf materials. Purdue’s 2021 account of the paint explains the development and its reported design.
Rank #2
- 10 Year Warranty
- Waterproof seal within 6 hours
- Cool Roof Technology with 80% reflectivity provides excellent energy cost savings
- Resists cracking in temperatures as low as -10 degrees Fahrenheit
- Ideal for metal roofs, concrete, modified bitumen, built-up, and weathered single-ply roofing systems
That distinction matters on a building project: a coating’s practical value depends not just on whiteness, but on measured solar reflectance and thermal emittance, as well as factors such as durability, substrate compatibility and application thickness. The cited sources do not establish those product specifications for a current retail coating based on this research.
What did the tests show—and what do the numbers mean?
The paper reports 98.1% solar reflectance and 0.95 sky-window emissivity for the BaSO4-acrylic paint. Its abstract separately reports that a BaSO4 film stayed more than 4.5 °C below ambient temperature during field tests or achieved an average cooling power of 117 W/m2. Those quantified field-test results are for the film; the paint is described as having similar cooling performance, not as having those exact film figures under every condition.
Rank #3
- This item is GARDNER-GIBSON SK-7705 STA-KOOL 770 ULTRA ELASTORMERIC ROOF COATING
- Used for Building Materials & Ladders Roofing
- This product is Manufactured in United States
Purdue professor Xiulin Ruan also estimated that covering a hypothetical 1,000-square-foot roof with the paint could provide 10 kW of cooling power. That is an attributed estimate, not a measurement of energy savings or air-conditioning performance in an occupied home. Weather, roof construction, installation and building heat loads would all affect real-world outcomes. Purdue’s news account gives the estimate and compares the paint’s reported reflectance with the group’s earlier coating.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Is the paint available to buy?
The cited sources do not establish current retail availability. Purdue reported in 2021 that patent applications had been filed, and the Sustainable Energy and Nanoscale Transport Laboratory says it is working with partners toward commercialization. Neither statement confirms a released product, a retail seller or a current specification sheet. Check for a manufacturer’s published performance and application data before treating any coating as the same formulation. See the Purdue Sustainable Energy and Nanoscale Transport Laboratory and the Cooling Technologies Research Center’s Cooling Paint page.
Quick Recap
Best Value
- WATER-RESISTANT PROTECTION: Provides a durable, water-resistant barrier for metal roofs. Ideal for outdoor use and helps prevent leaks in harsh weather conditions.
- RUST PREVENTION: Stops rust on metal roofing surfaces. Acts as a protective aluminum paint layer to extend the life of your roof and reduce maintenance needs.
- CRACK AND PINHOLE SEALING: Effectively seals hairline cracks and pinholes. Helps maintain a seamless finish and prevents moisture intrusion on metal roofs.
- HIGH SOLAR REFLECTANCE: Delivers over 50% solar reflectance per ASTM D2824, Type III. Reduces heat absorption and helps keep buildings cooler in sunny climates.
- VERSATILE ROOF COATING: Suitable for use as a metal roof paint sealer and compatible with elastomeric roof coating applications. Covers large areas with 640 fl oz size.
Rank #4
- Reflects Sun & Reduces Heat - This high temperature paint acts as a thermal insulation barrier, reflecting sunlight to lower surface temperature and improve indoor comfort as an effective insulating paint for roofs and walls.
- Withstands Extreme Weather & Temperatures - Formulated as a durable high heat paint, it resists cracking and peeling in conditions from -16°F to 212°F, offering reliable heat resistant protection for exterior surfaces year-round.
- Waterproof Seal & Dual-Layer Protection - This roof coating creates a seamless, waterproof barrier that seals out rain and moisture, providing combined thermal insulation paint and weatherproofing defense in one easy application.
- Easy DIY Application on Multiple Surfaces - This high temp paint is ready-to-use and designed for simple brush or roller application on metal roofs, concrete, siding, and other common exterior materials for a DIY project.
- Durable & Resilient Finish - Once cured, this thermal insulation paint forms a tough, flexible film that is resistant to wear, scrubbing, and weathering, maintaining its protective and reflective properties over time.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
Free tools Windows power users keep installed
One-click scans. No signup required.
