{"product_id":"cromar-bitumen-felt-adhesive","title":"Cromar Bitumen Felt Adhesive","description":"Cromar is a cold-applied, solvent-based bituminous adhesive designed for bonding multiple layers of roofing felt. Formulated for both ease of use and strong adhesion, this reliable product ensures a durable and lasting bond to bituminous membranes, providing a professional finish on flat roofing systems.\n\nIdeal for both residential and commercial applications, this adhesive delivers dependable performance whether you're working with timber, metal, concrete, or asphalt surfaces. Its black finish blends in seamlessly with most roofing materials.\n\n\u003ch3\u003eVersatile Uses\u003c\/h3\u003e\n\nThis adhesive can be used in a variety of roofing applications, including:\n\nBonding roofing felts to timber, concrete, asphalt, or metal\n\nActing as a lap cement for felt joins\n\nSecuring chippings to flat roofs\n\nIt’s also suitable for both first-time roof installations and repairs or refurbishments, making it a go-to product for roofers and DIYers alike.\n\n\u003ch3\u003eSurface Preparation and Application\u003c\/h3\u003e\n\nBefore applying, ensure the surface is clean and free of dirt, dust, oil, and loose debris. Any signs of algae or fungal growth should be brushed off and treated with a fungicide to prevent regrowth.\n\nThe adhesive can be applied using a stiff brush, mop, or squeegee. For best results in cold weather, store the container in a warm environment overnight before use. Once applied, the adhesive should be left for 15 to 30 minutes to develop a tacky layer before laying the felt. Carefully press or roll the felt into place to remove any trapped air and ensure a strong bond.\n\nOn timber roofs, the first felt layer must be nailed down, with additional layers bonded using Cromar adhesive. For porous concrete surfaces, a primer must be used first and allowed to dry thoroughly.\n\nLap joints should be 75mm on the sides and 150mm at the ends. For extra strength, adhesive can also be applied to the underside of the felt at lap areas before pressing down firmly.\n\n\u003ch3\u003eCoverage and Sizes\u003c\/h3\u003e\n\nEach litre of Cromar covers approximately 2m², depending on the surface condition and method of application. It is available in 1kg, 2.5kg, 5kg, and 25kg containers, supplied in either plastic or metal formats.\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\nSolvent-based, cold-applied bituminous adhesive\n\nExcellent bond to timber, metal, concrete, and asphalt\n\nIdeal for bonding felt, lap joints, and chippings\n\nEasy to apply with brush, mop, or squeegee\n\nProvides lasting waterproof adhesion\n\nAvailable in multiple container sizes\n\nBlack finish for a seamless appearance\n\nApprox. coverage: 2m² per litre\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\n\u003ch4\u003e1. Can I use Cromar in cold weather?\u003c\/h4\u003e Yes, but for best results, **store the adhesive in a warm room overnight** before use to avoid thickening. This will help maintain smooth and easy application during colder conditions. \u003cbr\u003e \u003ch4\u003e2. Do I need to use nails or just adhesive on timber surfaces?\u003c\/h4\u003e When applying to **timber roofs**, the **first layer of felt must be nailed down**. Successive layers can then be securely bonded using Cromar Roofing Felt Adhesive. \u003cbr\u003e \u003ch4\u003e3. What should I do if the concrete surface is porous?\u003c\/h4\u003e Porous concrete must be **primed first**. Make sure the **primer is completely dry** before applying the first layer of felt to ensure a strong and lasting bond.","brand":"JJ Building Materials","offers":[{"title":"25 ltr","offer_id":54802319901014,"sku":"954","price":41.97,"currency_code":"GBP","in_stock":true},{"title":"5 ltr","offer_id":54802319933782,"sku":"955","price":12.36,"currency_code":"GBP","in_stock":true},{"title":"1 ltr","offer_id":54802319966550,"sku":"33824","price":3.23,"currency_code":"GBP","in_stock":true},{"title":"2.5 ltr","offer_id":54802319999318,"sku":"33825","price":8.04,"currency_code":"GBP","in_stock":true}],"url":"https:\/\/jjbuildingmaterials.co.uk\/products\/cromar-bitumen-felt-adhesive","provider":"JJ Building Materials","version":"1.0","type":"link"}