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![\"A](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/cool-pavement-s-schmidt-2025-09-16-2-1024x768.jpg\")
Andrew Dodd with the city\u2019s Office of Sustainability measures the temperature of the CoolSeal pavement coating minutes after it was spread over a road in Hunting Park. (Sophia Schmidt\/WHYY)\n<\/p>\nThe first section of pavement, installed last summer, used just one coat of the CoolSeal coating. Within months, the coating had worn off in places and cracked, according to members of Composto\u2019s team.\n<\/p>\n
The city installed a double coat of CoolSeal on its second test patch this summer.\n<\/p>\n
The CoolSeal pavement costs around $0.60 to $0.80 per square foot, Dodd said. The city is spending a total of around $44,000 for the pilot project materials.
\nAndrew Dodd with the city\u2019s Office of Sustainability measures the temperature of the CoolSeal pavement coating minutes after it was spread over a road in Hunting Park. (Sophia Schmidt\/WHYY)\n<\/p>\n
Research has found limited benefits of cool pavement<\/p>\n
Cool pavement is already in use in places like Phoenix, Arizona, which coated over 140 miles of its roadways<\/a> with CoolSeal.\n <\/p>\n Phoenix\u2019s cool pavement pilot found that the CoolSeal coating lowered the roads\u2019 surface temperature by up to 12 degrees.\n<\/p>\n But the coating was much less effective at cooling the air. At best, air temperatures in Phoenix were less than 1 degree Fahrenheit cooler over the cool pavement than over the conventional asphalt. Still, researchers who evaluated Phoenix\u2019s pilot estimated that if applied throughout the city, the cool pavement\u2019s \u201csmall but beneficial\u201d<\/a> effect on air temperature could add up, and save residents millions of dollars on air conditioning costs each year<\/a>.\n<\/p>\n But Phoenix\u2019s pilot also found a concerning result: The CoolSeal coating bounced heat up onto pedestrians. The pilot found that the temperature that would be experienced by humans standing over the reflective pavement was roughly 5 degrees Fahrenheit warmer than over conventional asphalt during the hottest part of the day. So far, results are mixed in Philly<\/p>\n The Philadelphia researchers are still collecting data and analyzing the results of the cool pavement pilot in Hunting Park. So far, they\u2019ve found similarly mixed results.\n<\/p>\n The CoolSeal coating in Hunting Park appears to effectively lower the temperature of the road surface, but the Penn researchers have not found consistent evidence that it lowers the air temperature or would make a pedestrian feel cooler while walking above it.\n<\/p>\n \u201cWe didn\u2019t see a consistently negative impact,\u201d said Dorit Aviv, director of Penn\u2019s Thermal Architecture Lab. \u201cBut we don\u2019t see evidence of clear improvement for human comfort.\u201d\n<\/p>\n Aviv said solutions that stop the sun\u2019s energy from reaching the ground in the first place \u2014 for example, shading with trees or artificial canopies \u2014 may be more effective at cooling down city blocks.\n<\/p>\n In reality, cities may need to use a combination of strategies, Composto said.\n<\/p>\n \u201cYou mix and match the best approaches to mitigate urban heat,\u201d he said.\n<\/p>\n The city also hopes to test another potential benefit of the cool pavement coating: whether it could extend the life of the asphalt beneath it by insulating the road from heat stress.\n<\/p>\n What\u2019s next for Philly\u2019s cool pavement pilot<\/p>\n The Penn researchers and students plan to continue monitoring the durability of the CoolSeal coating at least through the winter, Composto said.\n<\/p>\n City officials will begin evaluating the results in fall of 2026, Dodd said. If the pilot shows promise, the city could consider applying CoolSeal pavement more broadly. If not, city officials will pivot to exploring other potential solutions, such as cool roof coatings, he said.\n<\/p>\n \u201cI just want to emphasize the fact that this is a pilot,\u201d Dodd said. \u201cHopefully we get some really good results.\u201d\n <\/p>\n","protected":false},"excerpt":{"rendered":"The first section of pavement, installed last summer, used just one coat of the CoolSeal coating. Within months,…\n","protected":false},"author":3,"featured_media":233961,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5132],"tags":[5229,114892,1448,2830,1311,12771,67,586,132,5230,68,2969,49740],"class_list":{"0":"post-233960","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-philadelphia","8":"tag-america","9":"tag-hunting-park","10":"tag-pa","11":"tag-pennsylvania","12":"tag-philadelphia","13":"tag-planphilly","14":"tag-united-states","15":"tag-united-states-of-america","16":"tag-unitedstates","17":"tag-unitedstatesofamerica","18":"tag-us","19":"tag-usa","20":"tag-whyy-news-climate-desk"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/115219999493318363","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/233960","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=233960"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/233960\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/233961"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=233960"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=233960"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=233960"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n![\"Workers](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/cool-pavement-s-schmidt-2025-09-16-5-1024x683.jpg\")
Streets Department employees spread CoolSeal reflective coating on a paved road near the Hunting Park Recreation Center. (Sophia Schmidt\/WHYY)\n<\/p>\n