{"product_id":"johns-manville-ventsulation-felt-venting-base-sheet-black-36-in-x-36-ft-roll","title":"Johns Manville Ventsulation Felt Venting Base Sheet, Black, 36 in. x 36 ft. Roll","description":"\u003ch1\u003eJohns Manville Ventsulation Felt Venting Base Sheet, Black, 36 in. x 36 ft. Roll\u003c\/h1\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eJohns Manville Ventsulation Felt is a venting base sheet for built-up and modified bitumen roofing systems installed over substrates that may contain moisture. Its 1 in. embossed waffle grid channels moisture vapor and helps prevent blistering. This listing is one Black 36 in. x 36 ft. roll, mineral-surfaced on one side.\u003c\/strong\u003e\u003c\/p\u003e\u003chr\u003e\u003ch2\u003eKey Features:\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVents moisture vapor:\u003c\/strong\u003e The 1 in. embossed waffle pattern grid channels promote moisture vapor venting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrevents blistering:\u003c\/strong\u003e Helps prevent blistering of asphalt-based roofs over potential moisture-containing substrates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIdeal for re-covers:\u003c\/strong\u003e Suited to re-covers over existing roof membranes and lightweight insulating substrates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensionally stable:\u003c\/strong\u003e Low moisture content and excellent dimensional stability make it an ideal replacement for organic base sheets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRot resistant:\u003c\/strong\u003e Resistance to rot supports long service life under the roofing system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMineral surfaced:\u003c\/strong\u003e Surfaced with coarse minerals on one side for a solid, stable substrate.\u003c\/li\u003e\n\u003c\/ul\u003e\u003chr\u003e\u003ch2\u003eSpecifications Table:\u003c\/h2\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eDetails\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eJohns Manville\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSell unit\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1 roll, 36 in. x 36 ft.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eProduct line\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eJM Ventsulation base sheets\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaterial\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eRoofing felt with embossed waffle pattern\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eColor \/ finish\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eBlack, coarse mineral surfacing on one side\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e36 in. x 36 ft. per roll\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNominal size\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e36 in. x 36 ft.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFeature\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1 in. embossed waffle pattern grid channels\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIntended use\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eVenting base sheet for BUR and modified bitumen systems\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eApproved applications\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eRe-covers over existing roof membranes, lightweight insulating substrates with potential moisture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003chr\u003e\u003ch2\u003eCoverage \u0026amp; How Much You Need:\u003c\/h2\u003e\u003cp\u003eEach roll measures 36 in. wide by 36 ft. long, covering 108 sq. ft. before laps. Install with the specified head and side laps and fastening pattern for the base sheet, so a single roll nets less than its full square footage.\u003c\/p\u003e\u003ch2\u003eFit and Compatibility:\u003c\/h2\u003e\u003cp\u003eUsed as the base sheet beneath any Johns Manville built-up or modified bitumen roofing system over potentially moisture-containing substrates such as re-covers over existing membranes and lightweight insulating fill. Membrane plys, adhesives and fasteners are installed over it and sold separately.\u003c\/p\u003e\u003chr\u003e\u003ch2\u003eFrequently Asked Questions (FAQ):\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eQ: What is included?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e One Black Ventsulation Felt roll measuring 36 in. x 36 ft., mineral-surfaced on one side.\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eQ: How much does one roll cover?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e A roll covers 108 sq. ft. before laps; deduct lap and fastening requirements when estimating.\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eQ: When should I use a venting base sheet?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e Use it when roofing over substrates that potentially contain moisture, such as re-covers over existing membranes or lightweight insulating fill, where blistering is a risk.\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eQ: How does the waffle pattern work?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e The 1 in. embossed waffle grid channels allow moisture vapor to vent, helping prevent blistering of asphalt-based roofs.\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eQ: What systems can it go under?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e It serves as a base sheet for any built-up roofing or modified bitumen roofing system.\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eQ: Can it replace organic base sheets?\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eA:\u003c\/strong\u003e Yes, its low moisture, dimensional stability and rot resistance make it an ideal replacement for organic base sheets.\u003c\/p\u003e\u003chr\u003e\u003ch2\u003eExpert Verdict — Reviewed by the SuperArbor Pro Desk\u003c\/h2\u003e\u003cp\u003eReach for Ventsulation Felt when a re-cover over an existing asphalt roof or moisture-prone lightweight insulating substrate risks blistering; the waffle channels relieve vapor pressure that would otherwise lift the new membrane. Fasten and lap the base sheet per JM's specifications before mopping or torching plies. It is not a finished roof layer, so always cap it with a full BUR or modified bitumen system.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eFollow safe roofing practices including fall protection and safe handling of hot asphalt, torches or adhesives used over the base sheet.\u003c\/em\u003e\u003c\/p\u003e\u003chr\u003e\u003cp\u003e\u003cstrong\u003eOrder Johns Manville Ventsulation Felt today to protect your re-roof from moisture blistering.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Johns Manville","offers":[{"title":"Default Title","offer_id":53522882888047,"sku":"JMVS","price":91.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0830\/3499\/7051\/files\/ProductImage_JohnsManville_VentsulationFelt.jpg?v=1790232437","url":"https:\/\/superarbor.io\/products\/johns-manville-ventsulation-felt-venting-base-sheet-black-36-in-x-36-ft-roll","provider":"Super Arbor","version":"1.0","type":"link"}