Intervention record · CHANGE4PLANET

The intervention

TIMELINE

WHAT WAS DEPLOYED

NYC CoolRoofs applies white elastomeric acrylic coating to existing flat, dark, low-slope roofs across New York City, and has done so since September 2009 [1]. Delivery is reported in cumulative square feet: more than 6.7 million square feet at a City investment of over US$4 million by the June 2017 Cool Neighborhoods NYC strategy [3]; over 9.2 million square feet by August 2018, including 1.5 million square feet in calendar 2018 against an annual goal of 1 million [2]; over 10 million square feet by April 2019, of which over 1 million square feet came from city-funded NYCHA roof replacements rather than program coating crews [1]; and over 12 million square feet by June 2025 [8]. An earlier count gives 5.7 million square feet across 626 buildings as at January 2015 [7]. Coating is free to non-profits, affordable and low-income housing, community and recreation centres, schools, hospitals and cultural institutions, and select cooperatively owned housing; other owners pay only for the coating material, with labour, technical assistance and equipment supplied by the program [4]. Independent measurement of the physical effect exists and is mixed. Instrumented monitoring of three white roofs in Queens, two against adjacent black membranes and one against an exposed black geotextile cloth, recorded summer 2011 average peak surface temperature differences of 23.6 degrees Celsius at an acrylic-painted asphaltic roof that had been freshly recoated on 25 May 2011, 23.7 degrees at a three-year-old EPDM membrane and 11.6 degrees at a four-year-old TPO membrane, with average daily differences of 6.6, 5.1 and 3.3 degrees [5]. The same study found the professionally installed membranes still met the Energy Star three-year aged albedo standard above 0.50, while the painted asphaltic surface, the technology this program applies, "lost about half of its initial albedo within two years of installation" [5]. A 2025 satellite study of 18,565 New York City census blocks that held a cool roof with average reflectivity at or above 65 in 2014 found 24.56 per cent had fallen below that threshold by 2020, with 57.39 per cent of that degradation occurring in the first two years of the window [6]. The program page lists benefit claims of up to 30 per cent lower internal building temperature and 1 ton of CO2 per 2,500 square feet coated, and attributes them to the New York City Panel on Climate Change 2015 Report, Chapter 6, rather than to measurement of coated buildings [4]. A further claim of 10 to 30 per cent lower air conditioning costs appears in agency press releases with no source attached [1][2], in the 2017 city strategy [3] and in a city network case study [7]. The 2017 strategy attributes an estimated 2,680 metric tons of CO2 equivalent to the program's first 6.7 million square feet [3].

HOW IT WORKS

Physical: a white elastomeric acrylic coating is roller-applied over an existing dark asphaltic, bitumen, modified bitumen or granulated cap sheet roof. The coating raises solar reflectance and retains high thermal emissivity, so the surface absorbs less shortwave radiation and re-radiates more of what it absorbs, lowering roof surface temperature, conducted heat into the top storey, and waste heat released to the air above the roof. The product monitored in New York, APOC 247 white reflective roof coating, is rated by its manufacturer at 0.87 initial solar reflectance; field-measured fresh albedo was lower than the rated value, and after two years the monitored surface had lost roughly 0.30 of albedo from a presumed initial 0.65 [5]. Emissivity measured on the acrylic surface was around 0.97 [5]. Administrative: the Department of Small Business Services funds and administers the program from city budget, contracts a non-profit workforce intermediary (The HOPE Program and Sustainable South Bronx) to recruit and supervise crews, and takes applications from building owners against a published eligibility list. Coating is delivered at no cost to a defined set of social-purpose owners and at the cost of materials only to everyone else; labour, technical assistance and equipment are supplied by the program [4]. Trainees are paid, work a ten-week programme with 300 hours of paid work experience and take OSHA 30 and related construction certifications; the delivery partner states a US$15 hourly wage [1][9]. The 2017 city strategy states that a study developed with Columbia University used the city's Heat Vulnerability Index to determine geographic areas of focus, assess clustering, prioritise participants and build outreach tools [3]; no fetched source states that the program adopted that targeting, though [6] reports high heat-vulnerable areas received 73 per cent of square footage installed in 2018.

The measurements

13 OUTCOMES

OUTCOMES

METRIC	VALUE	METHOD	MEASURED BY	INDEPENDENT	PERIOD	SRC
Cumulative rooftop area coated since September 2009 (operator milestone)	>10,000,000 square feet, reported as over 10 million; over 1 million square feet of the total is city-funded NYCHA roof replacement rather than program coating · baseline 0 (September 2009, program launch)	Program tally announced in an agency press release; no underlying building-level dataset published	NYC Department of Small Business Services	○	September 2009 to April 2019	[1]
Cumulative rooftop area coated since 2009 (most recent figure found)	>12,000,000 square feet, reported as over 12 million; for scale, total NYC rooftop area is given in the same article as 1.6 billion square feet · baseline 0 (2009, program launch)	Program figure reported in an independent news article; no underlying dataset published	NYC CoolRoofs, reported by Healthbeat	○	2009 to June 2025	[8]
Buildings coated	626 buildings, at over 5.7 million square feet (529,547 square metres) · baseline 0 (2009, program launch)	Program tally published in a C40 city network case study	City of New York, published by C40 Cities	○	2009 to January 2015	[7]
Annual delivery against the standing annual goal	1.5 million square feet coated in calendar 2018 against a 1 million square foot annual goal, announced as exceeded in August with months of the year remaining · baseline 1 (annual goal, million square feet)	Program tally announced in an agency press release	NYC Department of Small Business Services	○	calendar 2018 to 22 August 2018	[2]
Average peak roof surface temperature difference, white elastomeric acrylic coating recoated 25 May 2011, versus adjacent black membrane (MoMA Queens)	23.6 degrees Celsius (average daily difference 6.6 degrees; black membrane average peak 63.3 degrees, white 39.7 degrees) · baseline 63.3 (adjacent black membrane on the same roof, same period)	Continuous rooftop instrumentation: paired Apogee SI-121 infrared radiometers, back-to-back Kipp and Zonen CMP3 pyranometers for albedo, and a contact thermocouple, on a boom about 45 cm above the surfaces; the underlying black membrane had first received a coating in summer 2009 and the measured surface was freshly recoated on 25 May 2011, so the summer 2011 series measures a newly applied coating, not a two-year-old one	Columbia University Center for Climate Systems Research, NASA Goddard and NOAA-CREST at City College of New York, with two co-authors from NYC agencies	●	summer 2011	[5]
Average peak roof surface temperature difference, three-year-old white EPDM membrane versus adjacent black membrane (Con Edison Learning Center)	23.7 degrees Celsius (average daily difference 5.1 degrees; black membrane average peak 65.4 degrees, white 41.7 degrees) · baseline 65.4 (adjacent black membrane, same period)	Continuous rooftop infrared surface temperature sensors; monitoring from October 2008	Same research team	●	summer 2011	[5]
Average peak roof surface temperature difference, four-year-old white TPO membrane versus an exposed black geotextile cloth reference (Queens Botanical Garden)	11.6 degrees Celsius (average daily difference 3.3 degrees; black geotextile reference average peak 51.0 degrees, white 39.4 degrees). The black reference at this site had an average peak of 51.0 degrees against 63.3 and 65.4 degrees for the black membranes at the other two sites, so the three sites are not matched · baseline 51 (exposed black geotextile cloth at the same site, same period; the authors state this reference is not ideal)	Continuous rooftop infrared surface temperature sensors	Same research team	●	summer 2011	[5]
Albedo lost by the white elastomeric acrylic coating within two years of application		Back-to-back pyranometer albedo measurement over the coated surface, with photographic record of surface darkening; contributing factors discussed include ponding, runoff from rooftop infrastructure, exposure of granulated asphalt substrate and soot deposition near a busy road	Same research team	●	2009 to 2011	[5]
Census blocks holding a cool roof at reflectivity 65 or above in 2014 whose average reflectivity had fallen below 65 by 2020	24.56 % of 18,565 census blocks · baseline 65 (2014 block-average reflectivity threshold)	Retrospective longitudinal analysis of satellite-derived roof reflectivity on a 0 to 100 scale, built from cloud-free Landsat 8 imagery combined with New York State orthoimagery, shortwave albedo derived by the Ban-Weiss method and validated against Liang's method, aggregated to census blocks at two-year intervals	University of Pennsylvania, NYU Grossman School of Medicine, Hunter College CUNY, NYU Tandon and NYU School of Global Public Health	●	2014 to 2020	[6]
Share of all observed cool-roof degradation that occurred in the first two-year interval	57.39 % of degraded blocks, degrading between 2014 and 2016 (2016 to 2018: 28.44%; 2018 to 2020: 14.17%)	Same analysis	Same research team	●	2014 to 2020	[6]
Degradation by heat vulnerability: low heat-vulnerable versus high heat-vulnerable areas	27.03 % of 10,719 blocks in low heat-vulnerable areas degraded, against 21.20% of 7,846 blocks in high heat-vulnerable areas; the direction is the opposite of the study's hypothesis	Same analysis, stratified by the NYC Heat Vulnerability Index	Same research team	●	2014 to 2020	[6]
Share of program square footage installed in high heat-vulnerable neighbourhoods in 2018	73 % of the program's cool roof square footage installed that year	Program figure cited in the peer-reviewed degradation study's discussion	NYC CoolRoofs and The HOPE Program, cited by Bonanni et al.	○	2018	[6]
Estimated emissions reduction attributed to the first 6.7 million square feet	2680 metric tons of CO2 equivalent (estimated, not measured; the same document projects 3,500 tCO2e, US$1 million in annual energy cost savings and 500 New Yorkers trained by 2025)	City estimate published in the Cool Neighborhoods NYC strategy, sourced there to a Columbia University sustainability management capstone project, 2016; no underlying calculation published	City of New York	○	2009 to 2017	[3]

● independently measured○ operator-reported· not stated in any source

COST BASIS

CAPITAL: not published
OPERATING: not published
PER UNIT: 0.5 USD per square foot, total installed cost of white elastomeric acrylic coating applied by a trained volunteer organisation in New York City, materials and labour, as reported in the 2012 peer-reviewed monitoring study, excluding the cost of the underlying membrane [5]
FUNDING: 3
3 · 2600000
1
4
7

The US$0.50 per square foot figure is the installed cost of the acrylic coating route and excludes the underlying membrane. The same study's Table 1 gives, for comparison, professionally installed white single-ply membrane at US$15 to 18 per square foot with non-union labour and US$25 to 28 per square foot with union labour, for EPDM and TPO [5]. Those are membrane replacements, not coatings, and are the relevant comparison only at end of roof life. To the building owner the program's own cost is zero for non-profits, affordable and low-income housing, community and recreation centres, schools, hospitals and cultural institutions, and the price of the coating material alone for other owners, obtained at a discounted rate through participating vendors [4]. Dividing the reported over US$4 million against more than 6.7 million square feet [3] would give an approximate unit rate, but both terms are floors rather than exact figures, so no such figure is derived here. Recoating cost is the unresolved item: the 2012 study judged periodic recoating unlikely to be viable for owners because it imposes repeated costs of hundreds to thousands of dollars [5], and no fetched source describes a funded recoating cycle.

The assessment

PRECONDITIONS

A stock of flat, dark, low-slope roofs: the program will only coat roofs that are flat and of granulated cap sheet, asphalt, modified bitumen or bitumen construction [4]
The roof must not be cracked beyond a minimal degree and must be sound before coating; the coating is not a repair and is not applied over a failing roof [4]
Safe roof access without a hatch, ladder or window climb, a parapet stated as 3 feet 8 inches, and a roof free of machinery or equipment that would put crews at risk [4]
A workforce intermediary able to recruit, train, insure and supervise crews: the city hires 70 workforce participants a year through a ten-week paid programme delivered by a non-profit partner [3][9]
A recurrent municipal budget line rather than a one-off grant, since delivery is measured in square feet per year against a standing annual goal of 1 million square feet [2][4]
A targeting instrument: the 2017 city strategy used the city Heat Vulnerability Index to select geographies, assess clustering and build a priority list of 2.7 million square feet of candidate buildings [3]
Willing building owners, which requires the cost to be zero for social-purpose owners; other owners pay for coating material only [4]
A cooling-dominated summer where reduced solar absorption is a net gain. No fetched source quantifies a winter heating penalty in New York; the 2017 city strategy states negligible impact on winter heating costs [3], and the 2012 study found one low-emissivity white membrane ran slightly warmer than black in winter, which avoided a winter heat penalty at that building [5].
Unresolved precondition: a funded maintenance or recoating cycle. The 2012 study judged owner-funded recoating unlikely to be viable [5], and the 2025 study notes the program does not publicly detail its roofing materials or a formal maintenance plan [6]

OPERATOR HINDSIGHT

Stated in the sources. The 2012 monitoring study [5]: acrylic coating needs product research to identify conditions that hold long-term albedo, since the monitored surface lost roughly half its albedo in two years; owner-funded recoating is unlikely to be viable because it imposes repeated costs of hundreds to thousands of dollars; and at roof replacement only white membranes should be considered, because they cost the same as dark membranes. The 2017 city strategy [3]: better target coatings to the neighbourhoods that need them most, which produced a two-year strategic plan with Columbia University using the Heat Vulnerability Index to select geographies, cluster installations, prioritise candidate owners and build outreach tools, a priority list of 2.7 million square feet in the Bronx, Central Brooklyn and Northern Manhattan, and an intended institutional partnership model, the first named being Fordham University at six buildings and 81,000 square feet, which no fetched source confirms was delivered. The 2025 degradation study [6]: municipal maintenance initiatives are needed to sustain the heat mitigation potential of cool roofs; the program does not publicly detail its roofing materials or a formal maintenance plan, which the authors name as a barrier to evaluating it; and building-level rather than census-block data is needed to attribute degradation to materials, maintenance or environment.

TRANSFERABILITY ASSESSMENT

AXIS	SCORE	RATIONALE
CAPITAL INTENSITY	●●	Installed cost of US$0.50 per square foot including labour [5], and a reported City investment of over US$4 million by June 2017 [3]: routine municipal spending, not a capital program.
GOVERNANCE DEPENDENCY	●●	Delivered from 2009 as a voluntary program using existing agency budget, an existing workforce contract and building-owner consent; no fetched source records any legislation or new authority needed to run it [1][3][4].
ENVIRONMENTAL SPECIFICITY	●○	Benefit scales with the cooling season and the program will only coat flat low-slope roofs of asphalt, bitumen, modified bitumen or granulated cap sheet in good condition [4]; the 2017 city strategy states cool roofs have negligible impact on winter heating costs [3], and no fetched source quantifies a winter heating penalty in New York.
SKILLS AND MAINTENANCE	●○	Application needs a trained supervised crew rather than a specialist: a ten-week programme with 300 hours of paid work experience and OSHA 30 certification, 70 participants a year [1][3]; sustaining albedo needs a recoating cycle that no source describes as funded [5][6].
FUNDING REPEATABILITY	●●	Budgeted recurrently against a standing annual goal of 1 million square feet since at least 2014, exceeded in 2018 at 1.5 million square feet, and still delivering in 2025 [2][4][7][8].
POLITICAL DURABILITY	●●	Launched September 2009 [1], expanded under the de Blasio administration through One City: Built to Last and Cool Neighborhoods NYC [3][7], and still operating with cohorts scheduled for July and August 2026 [9]. No fetched source names the mayor in office at launch.

TOTAL 10/12 · T1

POLITICAL TEST

Survived at least one change of mayoral administration on the sourced record. NYC CoolRoofs launched in September 2009 as a volunteer program [1]; no fetched source names the mayor in office at launch. It was carried into the de Blasio administration's One City: Built to Last, released 21 September 2014, with an annual goal of 1 million square feet [7]; converted in 2015 from volunteer delivery to a paid workforce development programme [4]; and made a named heat mitigation strategy in Cool Neighborhoods NYC in 2017, which committed US$2.6 million of targeted projects through fiscal year 2020 [3]. It is still running under the current administration, with the Mayor's Office of Climate and Environmental Justice as the city climate partner [4] and trainee cohorts scheduled for 27 July 2026 and 24 August 2026 [9]. The city climate offices named as program partners change across that span: the Mayor's Office of Long Term Planning and Sustainability appears in 2012 [5], the Mayor's Office of Sustainability and the Mayor's Office of Recovery and Resiliency are both named as partners in 2017, 2018 and 2019 [1][2][3], and the Mayor's Office of Climate and Environmental Justice is the partner named on the current program page [4]. No fetched source states that any of these offices was a renaming of another.

The file

9 SOURCES

SOURCES

[1] government_press_release · In Celebration of Earth Day, City Announces Installation of Over 10 Million Square Feet of Energy-Saving Rooftops · New York City Department of Small Business Services · 2019-04-22 · en · PRIMARY · www.nyc.gov Full press release page fetched with browser headers and read in full (nyc.gov returns 403 to plain fetchers). Carries the September 2009 launch date, the over 10 million square feet milestone, the statement that city-funded NYCHA roof replacements account for over 1 million square feet of that total, the partner list, the eligibility and benefit claims, and the ten-week, 300-hour training structure. One page.
[2] government_press_release · City Sustainability Initiative Exceeds Annual Goal Months Ahead of Schedule: Over 9.2 Million Square Feet Installed Since 2009 · New York City Department of Small Business Services · 2018-08-22 · en · PRIMARY · www.nyc.gov Full press release page fetched with browser headers and read in full. Dated Tuesday, August 22, 2018 in the body although the URL slug reads 20180821. Carries the 1.5 million square feet delivered in calendar 2018, the 1 million square foot annual goal, and the over 9.2 million square feet cumulative figure. One page.
[3] government_strategy · Cool Neighborhoods NYC: A Comprehensive Approach to Keep Communities Safe in Extreme Heat · City of New York, Mayor's Office of Recovery and Resiliency · 2017-06 · en · PRIMARY · www.nyc.gov Full 46-page PDF fetched with browser headers and text-extracted; read the Strategically Implementing NYC CoolRoofs section, its figure captions and the endnote list. The document carries no printed date; the PDF creation timestamp is 14 June 2017, which is the basis for published_on. Source of the over US$4 million invested, more than 6.7 million square feet coated, 2,680 tCO2e estimated, 70 workforce participants a year, the US$2.6 million strategic implementation commitment through fiscal year 2020, the 2.7 million square foot priority list, and the Fordham partnership at six buildings and 81,000 square feet. The 6.7 million square feet and 2.7 million square feet figures are attributed in the document itself to a Columbia University Master of Science in Sustainability Management capstone project, 2016. Page 13 also carries the claim that a cool roof can lower air conditioning costs by 10 to 30 per cent, with endnotes pointing back to the agency's own web pages.
[4] operator_web_page · NYC CoolRoofs · City of New York, MyCity Business (Department of Small Business Services) · accessed 2026-08-16 · en · PRIMARY · nyc-business.nyc.gov Full page fetched with browser headers and read. Current program page: 2009 launch, the 2015 transition from volunteer to workforce development, the annual goal of 1 million square feet, the full rooftop eligibility list including the 3 feet 8 inches parapet requirement and eligible roof types, the no-cost and low-cost categories, and the benefit claims (roof surfaces up to 190F, internal temperature reduction up to 30 per cent, 1 ton of CO2 per 2,500 square feet), which the page attributes to the New York City Panel on Climate Change 2015 Report, Chapter 6. The page publishes no cumulative square-footage total. Undated, so published_on is null.
[5] peer_reviewed · Bright is the new black: multi-year performance of high-albedo roofs in an urban climate · S R Gaffin, M Imhoff, C Rosenzweig, R Khanbilvardi, A Pasqualini, A Y Y Kong, D Grillo, A Freed, D Hillel, E Hartung · Environmental Research Letters, volume 7, article 014029 (doi:10.1088/1748-9326/7/1/014029) · 2012-03-07 · en · PRIMARY · INDEPENDENT · iopscience.iop.org Open access full text fetched twice from the publisher page and read: abstract, site descriptions, instrumentation, Table 1 (product, installation cost, rated solar reflectance, age), Tables 2, 3 and 4 (summer 2011 peak and daily average temperature differences), the albedo decline discussion, the emissivity results and the conclusions. The publisher PDF was blocked, so no page count is stated. Independence is qualified: eight authors are from Columbia University Center for Climate Systems Research, NASA Goddard and NOAA-CREST at City College of New York, and two are serving New York City officials, D Grillo at the Department of Buildings and A Freed at the Mayor's Office of Long Term Planning and Sustainability. The paper does not state that the monitored acrylic roof was coated by NYC CoolRoofs; it states that the underlying black membrane had first received a coating in summer 2009 and describes the city initiative separately. Section 3.1.2 records a fresh acrylic recoating of the MoMA Queens surface on 25 May 2011, immediately before the summer 2011 measurement period; Section 3.3 states that the Queens Botanical Garden black reference is an exposed black geotextile cloth, which the authors describe as not ideal.
[6] peer_reviewed · Trends in cool roof solar reflectivity degradation in New York City (2014-2020): an important consideration for health-based evaluations of high albedo urban roofing interventions · Luke Bonanni, Anna Bershteyn, Mehdi Pourpeikari Heris, Andrea Titus, Hanxue Wei, Oyinkansola Babayode, William Rom, Alexander Azan · Frontiers in Sustainable Cities, volume 7, article 1655812 (doi:10.3389/frsc.2025.1655812) · 2025-10-02 · en · PRIMARY · INDEPENDENT · www.frontiersin.org Full open-access article fetched and read: abstract, methods, results, discussion, limitations and reference list. A Brief Research Report, not a full-length paper. Source of the 18,565 census blocks, the 24.56 per cent degradation by 2020, the 57.39 / 28.44 / 14.17 per cent split across the three two-year intervals, the 27.03 versus 21.20 per cent low and high heat-vulnerability split, the statement that high heat-vulnerable areas received 73 per cent of program square footage installed in 2018, and the finding that the program publishes neither its roofing materials nor a formal maintenance plan. Aggregation is at census-block level, not building level, which the authors name as a limitation.
[7] city_network_case_study · NYC CoolRoofs (case study) · C40 Cities Climate Leadership Group · 2015-01 · en · www.c40.org Full case study page fetched and read. Dated January 2015 on the page. Source of the 5.7 million square feet (529,547 square metres) across 626 buildings figure, more than 5,600 volunteers and more than 60 green job trainees, the statement that program coatings have reflectivity and emissivity ratings well above 0.8, the One City: Built to Last targets of 1 million square feet annually toward 10 million square feet and the 2025 projections, and the 2011 update to 2007 legislation requiring 75 per cent of roof area on new or substantially renovated low-slope roofs permitted on or after 1 July 2009 to have minimum initial solar reflectance 0.7 and minimum thermal emittance 0.75. C40 publishes member-city material, so this is treated as operator-derived rather than independent.
[8] news_report · NYC buildings trap heat. 'Cool roofs' program aims to lower temperature inside. · Niamh McAuliffe · Healthbeat · 2025-06-25 · en · INDEPENDENT · www.healthbeat.org Full article fetched and read. Most recent cumulative figure located: over 12 million square feet of roofs coated since 2009. Also gives the city's total rooftop area as 1.6 billion square feet, reports researcher Mehdi Heris as finding cool roofs on at least 36 per cent of the city's roofs and about 30 per cent of flat dark roofs as remaining candidates, cites 7 to 15 per cent cooling cost reduction from a Heris and Flohr study, relays a 2.2 to 5.9F maximum indoor temperature reduction in non-air-conditioned residential buildings without naming the study, and cites an estimated 580 premature heat-related deaths in New York City in 2024 from the 2024 NYC Heat-Related Mortality Report. The underlying Heris and Flohr work was not fetched, so figures attributed to it are recorded here as relayed by this article, not verified at source.
[9] operator_web_page · NYC CoolRoofs (delivery partner programme page) · The HOPE Program · accessed 2026-08-16 · en · PRIMARY · www.thehopeprogram.org Page fetched and read; sparse. Gives the US$15 hourly wage for jobseekers, the ten-week Monday to Friday 8 to 4 structure, the certification list (OSHA 30 Construction, 8-hour Fall Prevention, 2-hour Drug and Alcohol Awareness, Site Safety Training card, DOT 4-hour Site Safety Flagger, NYC DOB 4-hour Supported Scaffold User, CPR and First Aid), and cohort start dates listed as 27 July 2026 and 24 August 2026, the first of which had already passed at the access date, which is the evidence used here that the program is still operating. It publishes no square-footage total, building count or funding figure.

RECORD

PUBLISHED: 2026-08-16
LAST VERIFIED: 2026-08-16
REVIEW DUE: 2027-02-16
RUBRIC: v1.0
STATUS HISTORY: 2026-08-16 · operating · Record published.
2026-08-16 · operating · Second adversarial verification pass completed; evidence grade lowered to E4 and sourcing corrections applied.
RIGHT OF REPLY: Not yet exchanged. This record is an operating record and carries no failure analysis, but it publishes findings the operator has not addressed in public: that no exact cumulative delivered area or building-level dataset is published, that the program's stated energy and temperature benefits are cited to a climate panel report rather than to measurement of coated buildings, and that peer-reviewed work records the absence of a published maintenance or recoating plan. Right of reply will be offered to the New York City Department of Small Business Services, the Mayor's Office of Climate and Environmental Justice and The HOPE Program before this record is promoted or distributed, and any response received will be published here in full.
LANGUAGE: All sources are English-language publications of New York City agencies, two peer-reviewed journals, a city network and one news outlet. No translation was involved. The program styles itself NYC CoolRoofs, sometimes with a degree symbol before CoolRoofs in city documents; that typography is not reproduced here.
CONFIDENCE: Solid: the September 2009 launch date, the over 10 million square feet milestone and the NYCHA share of over 1 million square feet [1]; the 1.5 million square feet delivered in calendar 2018 against a 1 million square foot goal [2]; the over US$4 million invested, more than 6.7 million square feet, 2,680 tCO2e estimate, 70 participants a year, US$2.6 million commitment, 2.7 million square foot priority list and Fordham figures [3]; the eligibility criteria and cost structure [4]; the US$0.50 per square foot installed cost and the summer 2011 temperature differences [5]; and every degradation percentage [6]. All were read in the documents themselves, not in abstracts or secondary summaries. Thin, contested or absent: (a) No exact cumulative delivered area exists anywhere in the fetched sources. Every published total is a floor (over 9.2 million, over 10 million, over 12 million, more than 6.7 million), so none is coded as an exact number and the outcomes carry the inequality. The only exact-looking pair, 5.7 million square feet across 626 buildings, comes from a C40 case study dated January 2015 [7] and is not corroborated by a city document fetched here. (b) The most recent total, over 12 million square feet as at June 2025, was found only in a news article [8], not in a city publication; the current city program page publishes no total at all [4]. (c) No building-level dataset behind the tally was located; a search for a NYC Open Data cool roofs dataset did not surface one, and the 2025 study's authors independently record that the program does not publish its roofing materials or a maintenance plan [6]. (d) No annual program budget or exact cumulative expenditure is published, so capital_amount and operating_annual are null; the reported over US$4 million was not divided into a unit rate because both it and the matching area figure are floors. (e) The US$0.50 per square foot rate is from a 2012 paper [5] and is not restated in any current city source, so it may not reflect 2026 prices. (f) Neither independent measurement campaign measured program-delivered roofs as an identified set. The 2012 study monitored three roofs in Queens, one of them an acrylic coating applied in summer 2009 over asphaltic membrane, the same technology and the same year as the program's launch, but does not state that NYC CoolRoofs applied it [5]; the 2025 study measures all cool roofs at census-block aggregation regardless of who installed them [6]. (g) Independence of [5] is qualified: two of ten authors were serving NYC officials. (h) The three monitored sites in [5] were not matched: the black reference at Queens Botanical Garden had an average peak of 51.0 degrees against 63.3 and 65.4 degrees for the black membranes at the other two sites, so the smaller 11.6 degree difference there cannot be read cleanly as membrane ageing. (h2) The MoMA Queens acrylic surface reported at a 23.6 degree average peak difference was recoated on 25 May 2011, immediately before the summer 2011 measurement period, and the study shows the albedo record as a step function across that recoating. The temperature figure therefore describes a newly applied coating and must not be read as the performance of a two-year-old coating. (i) The albedo decline figure is the study's own approximation, roughly 0.30 from a presumed initial 0.65, and is flagged as approximate in the outcome. Reported initial solar reflectance for the TPO membrane appears as 0.79 in Table 1 and 0.88 in the manufacturer text of the same paper; neither is used here. (j) The 2012 paper reports a city strategic aim of 250 million square feet of white roofing by 2020, about 25 per cent of available New York City rooftop area [5]. That figure is not compared here against the program's delivered total, because it is not established whether the aim counted only program-coated roofs or all white roofing including code-driven conversion at roof replacement; a shortfall calculation would not be like for like. (k) The 36 per cent of city roofs already cool, the 7 to 15 per cent cooling cost reduction and the 2.2 to 5.9F indoor temperature reduction are relayed by a news article [8]; the underlying Heris and Flohr studies were not fetched, so they are not used as outcomes here. (l) The city's benefit claim of up to 30 per cent lower internal temperature is attributed by the city to a climate panel report, not to measurement of coated buildings [4]; the 10 to 30 per cent air conditioning cost claim appears in press releases [1][2] with no source attached, in the 2017 city strategy [3] with endnotes pointing back to the agency's own web pages, and in a city network case study [7]. Both are recorded as claims, not outcomes. (m) outcome_status is a judgement. Operating is supported by continuous delivery since 2009 and by cohort start dates in July and August 2026 [9]. Degraded was considered on the strength of the reflectivity findings in [6] and rejected because that degradation is measured across all New York cool roofs at block level rather than on program roofs, and delivery has continued; if a future study attributes measured reflectivity loss to program-coated roofs specifically, the status should be re-examined. (n) A NYC CoolRoofs program flyer PDF hosted at nyc.gov returned 403 and was not read, so nothing is cited from it. No figures were estimated, interpolated or derived by the registry; all nulls reflect absence in the sources.

CITE THIS RECORD

change4planet.org. C4P-URB-0004: White reflective roof coating at municipal scale (NYC CoolRoofs), New York City: delivery since 2009, and the albedo the coating does not hold. Grades T1/E4 (rubric v1.0). Last verified 2026-08-16. https://change4planet.org/records/c4p-urb-0004-nyc-coolroofs-usa