--- product_id: 69517418 title: "Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent." brand: "goberco" price: "€ 302.80" currency: EUR in_stock: true reviews_count: 13 category: "Goberco" url: https://www.desertcart.at/products/69517418-under-deck-drainage-system-50-ft-roll-with-16-in store_origin: AT region: Austria --- # 50 ft roll, fits 16 in joists Top-of-joist patented Z-fold design 30 mil heavy-duty waterproof membrane Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. **Brand:** goberco **Price:** € 302.80 **Availability:** ✅ In Stock ## Summary > 💧 Keep your deck dry, your space stylish, and your neighbors jealous! ## Quick Answers - **What is this?** Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. by goberco - **How much does it cost?** € 302.80 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.at](https://www.desertcart.at/products/69517418-under-deck-drainage-system-50-ft-roll-with-16-in) ## Best For - goberco enthusiasts ## Why This Product - Trusted goberco brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **No Proprietary Parts Needed:** Compatible with standard gutters and downspouts—save money and avoid specialty components. - • **Precision Fit for Standard Decks:** 50 ft roll tailored for 16-inch joist spacing minimizes waste and speeds installation. - • **Industrial-Strength Waterproofing:** 30 mil thick LLDPE membrane ensures long-lasting protection against moisture and weather. - • **Innovative Z-Fold Drainage Channel:** Patented design creates a 3.5-inch deep water channel that reduces leaks and acts as built-in flashing. - • **Top-of-Joist Installation Advantage:** Protects deck framing from moisture damage by mounting above joists, extending deck lifespan. ## Overview The Under Deck Drainage System by Goberco is a patented, heavy-duty 30 mil waterproof membrane designed for 16-inch joist spacing. Its unique Z-fold channel directs water efficiently into standard gutters, protecting deck framing by mounting on top of joists. Easy to install and compatible with common hardware, it creates a dry, usable space beneath decks while preventing costly moisture damage. ## Description Z/50/16 - Each roll is 50' long x 17 1/4'' width (for 16 in. joist spacing) x 30 mils thick - black astm heavy duty and durable polyethylene - top side is black, back side is Black - Easy to install and affordable: Goberco deck membrane + self-sealing tape + regular downspout total is under 2 $/s.f. - U.S. patent # 9,453,338 - unique Z-Fold/Channel allow membrane to act as flashing against house wall + 3.5'' deep valley between joists + a funnel to close the membrane against rim joist top. This means less risk of leaks at ledger board and at rim joist. Save time and money: no need of extra flashing and a piece of regular gutter downspout attach to membrane hole diverts water into the gutter so no need of expensive funnel. Review: Great system! - Installed this under a deck we are building on a brand new house. It installed fairly easily. We were installing it in 14 and 16 ft runs. It was a two-person job. We used the recommended 4" Grace vycor as our flashing. Also a great product It rained for the first time last night and the patio below is dry. I compared it to another system that installs like soffit underneath the deck boards. The thing that sold me on this system was this actually protects the top of the deck framing. Too many times I have had to tear down a deck because the pressure treated framing has finally deteriorated. I would recommend this to anybody who wants to waterproof under their deck. Review: Great customer service. - After an initial problem with shipping the company resolved the issue very responsibly. Great customer service. This product is not extremely flexible but is very workable. I am using it on 16 inch on center joists that are already tilted for drainage. The worst part is screwing the downspout on. I guess I'm not cutting it correctly. I have a very small gap at the corners of the cut. No problem. I'm just going to apply a small amount of silicone caulk around the spout on the underside. I'm using 6 inch wide butyl tape at the overlaps (Nashua window and door flashing tape from Home Depot. I've also used Trex Rainescape butyl tape but it's double the price). The product can be heated with a hair dryer or heat gun for molding. Overall, other than the shipping problem that the company fixed, I'm pleased with the product and would use it again. ## Features - CREATE A DRY SPACE BELOW YOUR DECK : Capture and redirect rainwater before it reaches the area beneath your deck. Perfect for creating a dry patio, storage area, workshop, or outdoor living space while helping protect your deck structure from moisture exposure - DESIGNED FOR 16 IN. JOIST SPACING: Each 50 ft roll is precision-sized to fit decks with standard 12 in. on-center joist spacing, helping simplify installation and reduce waste. - HEAVY-DUTY 30 MIL WATERPROOF MEMBRANE: Made from durable black polyethylene for exceptional strength, weather resistance, and long-lasting performance. - TOP-OF-JOIST INSTALLATION FOR SUPERIOR PROTECTION :Unlike many under-deck systems installed below the framing, Goberco mounts directly on top of sloped joists to help keep both the framing and under-deck area dry. The patented design also allows the membrane to act as flashing against the house wall. - NO PROPRIETARY ACCESSORIES REQUIRED: Uses standard gutters and standard downspouts available at most hardware stores. No expensive proprietary funnels, specialty downspouts, or brand-specific drainage components required. - PATENTED Z-FOLD DESIGN HELPS REDUCE LEAKS :U.S. Patent #9,453,338 features a 3.5 in deep drainage channel between joists and an integrated funnel design that efficiently directs water toward the gutter while helping reduce common leak points at the ledger board and rim joist. - HEAVY-DUTY INDUSTRIAL-GRADE MEMBRANE – Made from 30 mil thick Linear Low-Density Polyethylene (LLDPE) manufactured to ASTM standards for long-lasting waterproof performance. Each roll measures 50 ft long x 17.25 in wide for 16 in joist spacing. Made in Canada and designed for easy DIY or professional installation. - EASY TO INSTALL: 1. Staple on top of joists 2. Self sealing tape over joints 3. Screw downspouts to water evacuation holes. ## Technical Specifications | Specification | Value | |---------------|-------| | Manufacturer | Goberco Building Products inc. | | Part Number | 20130001 | | Item Weight | 11.88 pounds | | Item model number | 1725503016 | | Is Discontinued By Manufacturer | No | | Size | 50' long roll-for 16'' joist spacing-30 mil lldpe | | Color | Black | | Thickness | 0.75 Millimeters | | Item Package Quantity | 1 | | Outside Diameter | 10 Inches | | Cutting Diameter | 9.5 Inches | | Batteries Included? | No | | Batteries Required? | No | | Assembled Diameter | 9.5 Inches | ## Images ![Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. - Image 1](https://m.media-amazon.com/images/I/61HRx47WUuL.jpg) ![Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. - Image 2](https://m.media-amazon.com/images/I/61xbj-1Zj1L.jpg) ![Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. - Image 3](https://m.media-amazon.com/images/I/7125SPeElgL.jpg) ![Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. - Image 4](https://m.media-amazon.com/images/I/711VzqUfTiL.jpg) ![Under Deck Drainage System, 50 FT Roll with 16 in Joist, 3-in-1 Waterproof Membrane with Built-in Self-Flashing & Self-Funnel, Heavy-Duty 30 Mil, Top-of-Joist System, US Patent. - Image 5](https://m.media-amazon.com/images/I/81jwlVekmFL.jpg) ## Questions & Answers **Q: how do you deal with water at the fashia end of the joist run? I do not see down spouts listed** A: At the end of the joist bay staple the membrane on top of rim joist then make a hole. Attach a piece of gutter downspout ( about 8'' long ) to this hole, make sure each downspout piece drops far enough into the gutter to prevent wind from pushing water off the gutter. Please see installation video on GOBERCO's website. **Q: How do you account for accumulation of leaves, pine needles & helicopters falling from trees?** A: I usually account them one at a time. But to wash them away i have placed a drain system that allows removal. Just cut 4inch holes in a line opposite joist. Then place gutter under holes. Use gutter downspout pipe to direct flow into gutter. Then when accumulation occurs wash down, then slide out downspout pieces leaves and helicopters fall out. Been working for me. **Q: Is this material non-combustible or a class b fire rated material? I need it to pass hfz code in riverside county ca** A: Hello, NFPA Flammability rating is 1 (Slight), please send us an email then we will forward you the spec date sheet. Thank you. **Q: How many joist will a 50 foot roll do** A: For example a 50' roll will cover 4 joist bay of 12' long ( 12 x 4 = 48 ). If your joist are 16' long a roll can make 3 joist bay ( 16 x 3 = 48 ). ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great system! *by B***R on February 16, 2019* Installed this under a deck we are building on a brand new house. It installed fairly easily. We were installing it in 14 and 16 ft runs. It was a two-person job. We used the recommended 4" Grace vycor as our flashing. Also a great product It rained for the first time last night and the patio below is dry. I compared it to another system that installs like soffit underneath the deck boards. The thing that sold me on this system was this actually protects the top of the deck framing. Too many times I have had to tear down a deck because the pressure treated framing has finally deteriorated. I would recommend this to anybody who wants to waterproof under their deck. ### ⭐⭐⭐⭐⭐ Great customer service. *by R***S on October 22, 2025* After an initial problem with shipping the company resolved the issue very responsibly. Great customer service. This product is not extremely flexible but is very workable. I am using it on 16 inch on center joists that are already tilted for drainage. The worst part is screwing the downspout on. I guess I'm not cutting it correctly. I have a very small gap at the corners of the cut. No problem. I'm just going to apply a small amount of silicone caulk around the spout on the underside. I'm using 6 inch wide butyl tape at the overlaps (Nashua window and door flashing tape from Home Depot. I've also used Trex Rainescape butyl tape but it's double the price). The product can be heated with a hair dryer or heat gun for molding. Overall, other than the shipping problem that the company fixed, I'm pleased with the product and would use it again. ### ⭐⭐⭐⭐ Pros/Cons and Comparisons to competitors *by B***N on August 18, 2020* Pros: - Works great if it is being run with the slope of the deck (no need to worry about building your own slope). - A "funnel" can easily be created at the end of the run to channel water into a gutter. This is done by cutting two small pieces (~8-9" for 10" joists), facing and sloping them towards each other into the gutter. Cons: - As other people have mentioned, it is very difficult to work with at first. I suggest using a small 12" piece and don't fully tack it down for practicing. - Does not work well when the joists are parallel to the structure (house). There is no "natural" slope in this type of installation and requires you to create your own slope. - Creating a funnel like suggested in the video is not easy and requires extra time. Comparison to competitors: - Cheaper than Rain Escapes but more difficult to work with. - More expensive than EPDM rubber roofing but EPDM rubber requires more planning and at least one other person. I personally used EPDM roofing for most of my installation (my joists are parallel to my house) and then used this product to complete it when I ran out of rubber. I also used this to create "funnels" into my gutter. I would have given this a 5 star rating if it was a little easier to work with. ## Frequently Bought Together - Under Deck Drainage System -Z/50/16-50 feet Long Roll, for 16 inches Joist Spacing, 30 Mil Thick Trough, top Side Black + Down Side White. - Deck Flash Barrier, 3-In. x 75-Ft. - RainEscape Deck Drainage System Downspout - Black --- ## 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.at/products/69517418-under-deck-drainage-system-50-ft-roll-with-16-in](https://www.desertcart.at/products/69517418-under-deck-drainage-system-50-ft-roll-with-16-in) --- *Product available on Desertcart Austria* *Store origin: AT* *Last updated: 2026-08-20*