--- product_id: 335966796 title: "CHIMNEYRX Rx Elastomeric 1/2 Gallon" brand: "chimneyrx" price: "£138.90" currency: GBP in_stock: true reviews_count: 5 category: "Chimneyrx" url: https://www.desertcart.co.uk/products/335966796-chimneyrx-rx-elastomeric-1-2-gallon store_origin: GB region: United Kingdom --- # Water-resistant, weatherproof seal Easy brush-on application, no mixing Permanently flexible elastomeric formula CHIMNEYRX Rx Elastomeric 1/2 Gallon **Brand:** chimneyrx **Price:** £138.90 **Availability:** ✅ In Stock ## Summary > 🛡️ Seal Smart, Leak Less — Protect Your Roof Like a Pro! ## Quick Answers - **What is this?** CHIMNEYRX Rx Elastomeric 1/2 Gallon by chimneyrx - **How much does it cost?** £138.90 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/335966796-chimneyrx-rx-elastomeric-1-2-gallon) ## Best For - chimneyrx enthusiasts ## Why This Product - Trusted chimneyrx brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Weather Warrior:** Creates a durable, weatherproof barrier against rain and moisture - • **Broad Compatibility:** Bonds seamlessly with asphalt shingles, aluminum, brick & more - • **Coverage That Counts:** Half-gallon covers up to 14 sq. ft. for full flashing protection - • **Effortless Application:** Brush-on ready formula—no mixing, no fuss - • **Leak-Proof Flexibility:** Stays flexible to prevent cracks and leaks over time ## Overview CHIMNEYRX Rx Elastomeric 1/2 Gallon is a premium elastomeric sealant designed to permanently stop leaks around chimney flashings, skylights, stacks, and vents. Its flexible formula resists brittleness unlike traditional tar-based sealers, ensuring long-lasting protection. Easy to apply with a brush (not included), it requires no mixing and cleans up with soap and water. Each 1/2 gallon container covers approximately 14 square feet, bonding effectively to asphalt shingles, aluminum, brick, and other roofing materials to create a durable, weatherproof seal. ## Description Use CHIMNEYRX Flashing Sealant to Repair Chimney Flashing Leaks. CHIMNEYRX Elastomeric Flashing Sealant is an elastomeric sealant specially formulated to permanently adhere to asphalt shingles, aluminum flashing, brick and other chimney and roofing materials. Faulty or deteriorated flashings can cause leaks and water damage to the surrounding roof deck or eventually the interior finishes of your home. Unlike tar-based sealers, CHIMNEYRX Elastomeric Flashing Sealer is an elastomeric-based material that remains flexible over longer periods of time. When applied, it will resist the typical brittleness and ing associated with tar-based sealers that ultimately leads to their failure and need for replacement. CHIMNEYRX Elastomeric Flashing Sealant is excellent for use in stopping problem leaks around the base of chimneys. When used to repair chimney flashing leak at the base of a chimney, CHIMNEYRX Elastomeric Flashing Sealant provides a weatherproof “boot of protection” for the chimney. It is also great for sealing around skylights. Repairing flashings that have been tarred, re-tarred or ed has never been so easy. Available in 1/2 gallon plastic containers, each container covers approximately 14 square feet. Brush not included. Review: I really like this product! I like to maintain the flashing around my masonry chimney and I've always done it with a dab of some product here and there, but it is easy to miss an area that might have a gap if it is small. Last year we had an 11" rain here in WI and sure enough, just a small amount of water did leak in around the chimney. With this product you "paint" it over the entire flashing and where it meets the roof and the brick, so there are no missed areas - the entire thing is coated. The product applied quite easily - it's is fairly thick, but it did go on and brush out with a regular paint brush. I followed the instructions and masked the roof and the brick with duct tape and then applied the product. Once done, just remove the tape and you have an amazing looking job! In the on-line instructions the coverage is listed at 14 - 18 sq ft at a thickness of 1/8" for the 1 gallon size. In the desertcart listing it is listed as 12 sq ft, but the product is only 1/2 gallon, so that is not correct. I did 10 sq ft and used about half of the 1/2 gallon container. I would think I must have applied it about 1/16" thick. It is very hard to get an exact thickness when you are applying it. Review: Purchased this to seal around chimney. Applied it over fibreglass cloth and it worked beautifully. Looks great and stays flexible. Easy to apply. ## Features - Stops Leaks Around Chimney Flashings, Skylights, Stacks, & Vents - Remains Permanently Flexible to Stop Chimney Leaks - Easy Brush-On Application (Brush Not Included) - Ready to Use, No Mixing Required, Cleanup With Soap & Water - 1/2 Gallon Covers 14 Sq. Ft. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B0060NKMOU | | Brand Name | CHIMNEYRX | | Color | Black | | Compatible Material | Plastic | | Customer Reviews | 4.6 4.6 out of 5 stars (263) | | Item Dimensions | 30.5 x 30.5 x 30.5 centimeters | | Item Form | Liquid | | Manufacturer | SaverSystems | | Material Type | Plastic | | Model | BHBUKPPAZINH2401 | | Part Number | 300054 | | Style Name | Compact | | Surface Recommendation | Roof | | UPC | 709057942645 709057941648 | | Water Resistance Level | Water Resistant | ## Product Details - **Brand:** CHIMNEYRX - **Item dimensions L x W x H:** 30.5 x 30.5 x 30.5 centimeters - **Material:** Plastic - **Style:** Compact - **Water resistance level:** Water Resistant ## Images ![CHIMNEYRX Rx Elastomeric 1/2 Gallon - Image 1](https://m.media-amazon.com/images/I/81+13WKLBRL.jpg) ![CHIMNEYRX Rx Elastomeric 1/2 Gallon - Image 2](https://m.media-amazon.com/images/I/71dAEaX5VoL.jpg) ![CHIMNEYRX Rx Elastomeric 1/2 Gallon - Image 3](https://m.media-amazon.com/images/I/71z3FnIeHKL.jpg) ![CHIMNEYRX Rx Elastomeric 1/2 Gallon - Image 4](https://m.media-amazon.com/images/I/71IUh7QJYeL.jpg) ![CHIMNEYRX Rx Elastomeric 1/2 Gallon - Image 5](https://m.media-amazon.com/images/I/71nOuZgw6eL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Review *by T***R on 17 August 2019* I really like this product! I like to maintain the flashing around my masonry chimney and I've always done it with a dab of some product here and there, but it is easy to miss an area that might have a gap if it is small. Last year we had an 11" rain here in WI and sure enough, just a small amount of water did leak in around the chimney. With this product you "paint" it over the entire flashing and where it meets the roof and the brick, so there are no missed areas - the entire thing is coated. The product applied quite easily - it's is fairly thick, but it did go on and brush out with a regular paint brush. I followed the instructions and masked the roof and the brick with duct tape and then applied the product. Once done, just remove the tape and you have an amazing looking job! In the on-line instructions the coverage is listed at 14 - 18 sq ft at a thickness of 1/8" for the 1 gallon size. In the Amazon listing it is listed as 12 sq ft, but the product is only 1/2 gallon, so that is not correct. I did 10 sq ft and used about half of the 1/2 gallon container. I would think I must have applied it about 1/16" thick. It is very hard to get an exact thickness when you are applying it. ### ⭐⭐⭐⭐⭐ Review *by B***N on 19 November 2025* Purchased this to seal around chimney. Applied it over fibreglass cloth and it worked beautifully. Looks great and stays flexible. Easy to apply. ### ⭐⭐⭐⭐⭐ Review *by E***A on 2 June 2023* I was a bit concerned when I opened the shipping box and saw that the lid of the plastic tub had leaked a bit, as though the lid may have popped from pressure during shipping. Sealer seemed ok. We assumed that our interior ceiling leak was from the chimney flashing. The sealer was brushed liberally around and on the flashing. The next 5 days we had heavy downpours. No interior ceiling leaks. Very pleased. ## Frequently Bought Together - ChimneyRx 300054 Brushable Chimney Flashing Repair Sealant – Black Elastomeric Waterproof Coating Leak Protection for Chimneys, Vents & Skylights - Bonds to Shingles, Bricks, & More - 1/2 Gallon - ChimneyRx 300014 Brushable Chimney Crown Repair – Elastomeric & Waterproof Coating for Crowns & Masonry - Fast-Setting & Long-Lasting Protection Crack & Leak Prevention - 1 Gallon - ChimneyRx 300119 Masonry Chimney Water Repellent - Siloxane Based, Non-Film-Forming, Breathable, and Transparent Waterproof Coating for Brick Chimneys & Other Vertical Surfaces - 1 Gallon --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/335966796-chimneyrx-rx-elastomeric-1-2-gallon](https://www.desertcart.co.uk/products/335966796-chimneyrx-rx-elastomeric-1-2-gallon) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-06-25*