It looks like this is a web page, not a feed. I looked for a feed associated with this page, but couldn't find one. Please enter the address of your feed to validate.

Source: https://atlanta-insulation.com/understanding-r-values-a-guide-to-choosing-the-right-insulation/

  1. <!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol","Noto Color Emoji"}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;padding-left:1.5rem;max-width:60rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{line-height:2.25rem;font-size:1.5rem;font-weight:500}@media (width <= 720px){.h2{line-height:1.5rem;font-size:1.25rem}}#challenge-error-text{background-image:url("data:image/svg+xml;base64,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");background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme: dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="360"></head><body><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt = {cvId: '3',cZone: 'atlanta-insulation.com',cType: 'managed',cRay: '9801b94e099eed75',cH: '5clSCrROBeVIXR9PZQISAEN7bbIeFvBJQFt3bsNdJ4U-1758039968-1.2.1.1-dmsJcQoZeO4b1FrVNoapxh5rytRJhgSU2YsjcDKCZQe_p.FopkxeOtay4kQt2bTD',cUPMDTk:"\/understanding-r-values-a-guide-to-choosing-the-right-insulation\/?__cf_chl_tk=WB8pGSrFoRN5B5TYidYXjcpwW_yV1xW8jB0HkY5XhVc-1758039968-1.0.1.1-UjGUakU9CT8yhP8z1_VCROUO8W5FQiukPDqTajkO1fs",cFPWv: 'g',cITimeS: '1758039968',cTplC:0,cTplV:5,cTplB: 'cf',fa:"\/understanding-r-values-a-guide-to-choosing-the-right-insulation\/?__cf_chl_f_tk=WB8pGSrFoRN5B5TYidYXjcpwW_yV1xW8jB0HkY5XhVc-1758039968-1.0.1.1-UjGUakU9CT8yhP8z1_VCROUO8W5FQiukPDqTajkO1fs",md: 'VxGwoQ0GDEwiK0DlrtZ0eGZUyyXfdhCp6qS5_g.nviA-1758039968-1.2.1.1-oL9NVEpwNy.rlybfsEY0.pZCJOGmTNvtyflkeh7HRAdmNZSFHNlNUeN8uQV309Q6NHNRB3B.pMkGKtFTkvM2lZcU.6LiuCq7CFceoMcWO.b0ZUF6B3bL3kGlGFpxrzXdLXDSVznK4quXIWifXxWU.31FdPUFJVv0sOTtieKNuAWDnNa1Q0xBXvx9Sqx_pp9y7efBTRWl4zO.NO70kt4besEy3ObvWeVhyAc3.CudkNSFIYkoJGoykjE7sT.pCHIvl.7iC0HQjxLJjAECM3IQPc97EAb0dflnEeLt6yilW9e2K2Cf2_A8XtD_Fc7MFCP94MIcqkbvCB0CCzsPokjl19SQLmpqGMoxqBu3LZrQE564SdrXYLl0xjDYyxVae3UXl86jvRlkXfTLZOipexcHbCM.XuAfTDzWdy4Sym_.ERESElrYYWy2527enC1ulstyFHsoIgceuJ_piHv7HlGf3gjUlY7w64znkYugaMNSttxPV0yc6yKDrPQDydJpEKvR87Bj2i3MYDUC9VFWf.79zVitPr1_zl7oB69NUVvLpAD0A7jlX7KejBro2GbcCXrdDqpDGK4019avB0JyNloXzmUjea3b3mCfJWw8oqW3vJ1MHSawD.Y0Ztdm8OIWR2X6sQpIQk2XmJHWTwq18zpcgwiiRgWlab45jqCmdKDrrno0WqJv2c8jUcL1W9O7TUpJP7Yc0XkQXryZyFZu1IQ06ytuItzfVBFyQIZxahc6T1woOHgXVbYUlhvim_HmAphTA_b5vSIRdsNmFwD39vT5lA8MgwrFLWwjRdMzIE0Ye4yiDUYc6q._8h9YHiMHv63UtuOWaNE6h4De0oJIluR766d5F6222dtjEwGUWjcvr0BcDyuhTq4Aa44dFcKij8dNOxSaVGaD1LUeMre_a0_n6Q',mdrd: 'uSYmb2bBfwjD2.Yqttn0T1GLjh.9gAZBPMYuhVPe_vY-1758039968-1.2.1.1-x2GNUMo9K9ZuP_fBCd8AJwbJf2Tm4ldaEFRIPSyiXw2youNilfj9trD5945yIBQXzhgzKWGsHsCN.QINjaUUQ6uSU864kJi1n_wNB2ZwcrXIC.ML0czKXVps1HNraz.5Z9sP7RgQWqD46ca6P0O5DVeUhLBEu6zOBXkwGzHs_hPArelniqgx3i4q6tPrFfHpPkQK4P00lcKEV1uVEm82FPd7wctJwECGBZDiE1y5Aolv3xWR85LexV0LVUC814_O8cwMX0UyoSUZ6GgrKlUSL_iS0Lwu01kGxWI8YRvyrMLq0mpmKeuKD7doUdVuIrI7LAkjeM1fhdK9oTZorJV0EuwJba.VhUwLDkSJAPMy_uDccM3zyvb40mpuNJf0jZHpClJ1YRAGGrXDCLNn0T4jdxdKkxpIdVw9Aj6jTVDfuk0cY85sUbQ3Kl4nbKwZPuMuV6xlCchsA6RTWDDoq.FoW.WZCHiJfymcJ_YzB6_ThAoqx_naHwXXAezAEwmULWE0P5YfWFjKAFiIwRDt7.ty3uLHzMaTJGNR811VACrsQ.xt2SSS3tnLAnj_ASZR3liy2MXgKzX91w3KlwCkPu5aWiRYP2F4SWMvQ3hd0AoyIz4lDydbJ0JAnKJI_xJM.N7MOp1FlJetKvZwVN_2Rz.ffMxZUdoSQcd2zwuJQNqhHvTTF57qxIzt2bRo5HTbe2C6FtTZ277aiz05pXWDA5T1KM2.TGHQoQgkObsnDPL3M5nMiGQ78oiEmfATYmI6naTx6tyUqJA2xiUBl9M3evNSyMken5iajHHUdNG6kw8A.2rTezpSTko71hLQxb4QD2JQ4NTzIIvFwJAxmBKV5ssc24LyF7Wo6Udmf148si91QBJoctQnIS6J3WR5lOwzRdNcV9y_BkSn1IS4gDChFN1AcxqlF_QKB2rQo1ji634Dwq1GUHymNkOBsnyu3z7aXbeie7oixKvnPgZkzQIw8x5_lRwR0R3VAn3_RpmuPakzUZuZAmkXBDk5rYiEoIM3Pvr2FS3ZWqwmOk61ICDovHyWkhDmWcKhPvVd3Dn82_iyKiUm0jfMVHS_xZppJHYC2ay09LMgiCiN3nbzVjnsWWy2NAyMH8n74xvMRyongtqVNxhUCAGr8NygX9GbRbFD92lHAT9Pn6dL4RQHoK1NkBchEO5EqktMFfsc.PVAa2CdfIiZ_3YHzDsZtTyMXrWeCqEbJ446FaGZ36ils1_I2_SiFiupxFZR8cFoFw9Sc8aMjD1YaOOOzJjfyWM.DFdoFZAGqHr58IZ07CvL33kC0kAgfnQwa3mBXPscwOw1n_J3YTF8lMb5t4qk4SB5T3hRPDch5jeqEbrI4wg7p9E9k0QvACE.qIRpba9c0CIw7jKYEijDvZQ3HZ5C0QLgjE4LwfJmaksqj1xr_aTNHEqjZFuFDR1fZMh9tVLST1CjKKsyv7Fs5CsUhII7yIePGCwdf1Tr6aprymIv0fw6ZiQ0YwedXNBm43kiruh_OxyllDjWqP1He5ZEIElDP81xJ58sexDcqoqFliO2Uk2DLX_2Np7DZ.Sp_N5RIcX9g.gL5lW6Jxzzatxibj5YxbnzhwI.CCnHGWP3AtKR6HjTlbTrgmnQKqB3xc2ztYbnlZ2A2YQSpKNfXyMxul8LRQIK4LDj_mX8D6RhbIjuybwArGn._lDbeKKrifPfrcAPVXnBmK2uArlolJAZ9BVvGEiDwOI_iA9.Vtw08VAHfYirLyzx3VntRqeshgytSoNRjZf1qfV_AdjmsUUgTOpitrYGpgzyoxciWQP8vkYaID0GNyco3P5ztGw0DDp8uxiNwElm.h0Q4CEERRRorGlqsxwMWW.xdrg7wwn9FE1r3f8X3CQYCbmy3II.kfftfeNxCuBnzdZAwD2CismDhCjE2QtVQXGvfRGJ',};var a = document.createElement('script');a.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=9801b94e099eed75';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null,"\/understanding-r-values-a-guide-to-choosing-the-right-insulation\/?__cf_chl_rt_tk=WB8pGSrFoRN5B5TYidYXjcpwW_yV1xW8jB0HkY5XhVc-1758039968-1.0.1.1-UjGUakU9CT8yhP8z1_VCROUO8W5FQiukPDqTajkO1fs"+ window._cf_chl_opt.cOgUHash);a.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(a);}());</script></body></html>
Copyright © 2002-9 Sam Ruby, Mark Pilgrim, Joseph Walton, and Phil Ringnalda