{"product_id":"m-d-building-products-71480-backer-rod-1-2-in-x-20-ft-gray","title":"M-d Building Products 71480 Backer Rod 1\/2 in X 20 Ft Gray","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe M-D BUILDING PRODUCTS 71480 is a closed-cell polyethylene backer rod designed for use before caulking in gaps and openings larger than 1\/2 inch wide by 1\/2 inch deep. The nonabsorbent, closed-cell construction prevents moisture intrusion into the foam itself, keeping the backing material stable over time. Its primary function is to control caulk depth and prevent three-point bonding, which can cause premature caulk failure at joints and seams. Installers in construction, weatherization, and building envelope work rely on this type of pre-caulking material to produce durable, properly dimensioned caulk joints on both interior and exterior applications.\u003c\/p\u003e\u003cp\u003eThis backer rod is suited for residential and light commercial projects where gaps or control joints exceed 1\/2 inch in both width and depth. Common applications include expansion joints, window and door frames, concrete control joints, and masonry openings where a proper caulk backing is needed to achieve a two-sided bond. The 20-foot roll length makes it practical for single-joint runs or multiple smaller fills on a job site without excessive material handling.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eClosed-cell polyethylene construction resists moisture absorption\u003c\/li\u003e\n\u003cli\u003ePrevents three-point bonding for longer-lasting caulk joint performance\u003c\/li\u003e\n\u003cli\u003e1\/2 inch diameter fits gaps and openings larger than 1\/2 inch x 1\/2 inch\u003c\/li\u003e\n\u003cli\u003e20-foot roll provides continuous length for single or multiple joint fills\u003c\/li\u003e\n\u003cli\u003eNonabsorbent material maintains shape and density after installation\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as a pre-caulking backer for use with standard caulks and sealants in gaps and openings larger than 1\/2 inch wide by 1\/2 inch deep on residential and commercial building envelope joints.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eBacker rod is typically installed by construction trades, weatherization contractors, or skilled DIYers working on building envelope sealing. Press the rod firmly into the joint so it seats at the correct depth, leaving adequate space for the caulk bead above it. Do not stretch or compress the rod excessively, as this can alter the diameter and affect caulk depth control. Ensure the joint is clean and dry before installation to promote proper sealant adhesion.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Closed-cell polyethylene\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiameter\u003c\/strong\u003e: 1\/2 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLength\u003c\/strong\u003e: 20 feet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor\u003c\/strong\u003e: Gray\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.132 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCell Type\u003c\/strong\u003e: Closed-cell, nonabsorbent\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: M-D BUILDING PRODUCTS\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 71480\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"M-D BUILDING PRODUCTS","offers":[{"title":"Default Title","offer_id":51347894370610,"sku":"71480","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/310549644.jpg?v=1782115651","url":"https:\/\/voomisupply.com\/products\/m-d-building-products-71480-backer-rod-1-2-in-x-20-ft-gray","provider":"Voomi Supply","version":"1.0","type":"link"}