--- product_id: 1889812 title: "636 Steel Roof Vent Cap for 3\" and 4\" Round Duct, For Bathroom Ventilation Fans, Black" brand: "broan-nutone" price: "$111.09" currency: USD in_stock: true reviews_count: 13 url: https://www.desertcart.us/products/1889812-636-steel-roof-vent-cap-for-3-and-4-round store_origin: US region: United States of America --- # Built-in bird screen keeps pests out Backdraft damper prevents unwanted airflow Steel construction for lasting durability 636 Steel Roof Vent Cap for 3" and 4" Round Duct, For Bathroom Ventilation Fans, Black **Brand:** broan-nutone **Price:** $111.09 **Availability:** ✅ In Stock ## Summary > 🌟 Elevate your ventilation game with the stealthy, durable Broan-NuTone 636! ## Quick Answers - **What is this?** 636 Steel Roof Vent Cap for 3" and 4" Round Duct, For Bathroom Ventilation Fans, Black by broan-nutone - **How much does it cost?** $111.09 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/1889812-636-steel-roof-vent-cap-for-3-and-4-round) ## Best For - broan-nutone enthusiasts ## Why This Product - Trusted broan-nutone brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Universal Fit:** Designed to seamlessly fit both 3" and 4" round ducts, making installation effortless on pitched roofs. - • **Durable Steel Build:** Engineered with premium steel and a sleek black powder coat for long-lasting performance and style. - • **Pest-Proof Protection:** Integrated bird screen ensures your ventilation stays clean and critter-free—no more unexpected guests. - • **Optimized Airflow Control:** Backdraft damper blocks reverse airflow, maintaining fresh air circulation and energy efficiency. - • **Trusted Ventilation Solution:** Perfect for bathroom and home gym fans, enhancing air quality while blending into your roofline. ## Overview The Broan-NuTone 636 Steel Roof Vent Cap is a robust, easy-to-install ventilation solution designed for 3" and 4" round ducts. Featuring a durable steel construction with a black powder coat finish, it includes a backdraft damper and bird screen to prevent reverse airflow and pest intrusion. Ideal for bathroom and recreational room fans, this vent cap ensures reliable, efficient rooftop ventilation while maintaining a sleek, low-profile appearance. ## Description The Broan-NuTone 636 Steel Roof Vent Cap is an easy-to-install vent for ventilation fans (bathroom, rec room, home gym, etc.). This vent cap provides reliable roof top ventilation and features both a back draft damper and bird screen, preventing outside air from entering the home and birds and small animals from entering duct work. Compatible with 3" and 4" ducting. Not suitable for dryer venting or flat roofs. ## Features - HIGH-QUALITY ROOF CAP: Steel roof cap for use with bathroom ventilation fans to maximize the air and sound performance of your bath fan - RELIABLE: Includes a built-in, backdraft damper and bird screen to provide a dependable roof cap you can rely on - DURABLE: Constructed of steel with a black powder coat finish to ensure durability and lasting use - EASY INSTALLATION: Roof cap is designed to fit with either a 3" or 4" round duct to provide a simple pitched roof installation ## Technical Specifications | Specification | Value | |---------------|-------| | Additional Features | Backdraft Damper, Bird Screen | | Asin | B000BQW6LE | | Best Sellers Rank | #27,327 in Tools & Home Improvement (See Top 100 in Tools & Home Improvement) #34 in HVAC Ducting | | Brand Name | Broan-NuTone | | Color | Black | | Customer Reviews | 4.5 4.5 out of 5 stars (782) 4.5 out of 5 stars | | Finish Types | Black | | Global Trade Identification Number | 00026715000609 | | Included Components | Roof Cap, damper, birdscreen | | Item Dimensions D X W X H | 30"D x 8"W x 6"H | | Item Form | Roof | | Item Type Name | Roof Vent Cap Only | | Item Weight | 1.6 pounds | | Manufacturer | Broan-NuTone | | Manufacturer Part Number | 636 | | Material Type | Steel | | Model Number | 636 | | Mounting Type | Roof Mount | | Number Of Items | 1 | | Unit Count | 1 Count | | Upc | 696335226149 026715000609 049403210210 735090814458 | | Ventilation Type | Ducted/Vented | | Warranty Description | 1 Year | ## Product Details - **Brand:** Broan-NuTone - **Color:** Black - **Finish Type:** Black - **Product Dimensions:** 30"D x 8"W x 6"H - **Special Feature:** Backdraft Damper, Bird Screen ## Images ![636 Steel Roof Vent Cap for 3" and 4" Round Duct, For Bathroom Ventilation Fans, Black - Image 1](https://m.media-amazon.com/images/I/51+ICBj7SbL.jpg) ## Available Options This product comes in different **Size** options. ## Questions & Answers **Q: What is the function of a roof vent cap? Does it keep rain water out of house, or just keep animals out?** A: It does both keeps rain and animals and bugs out. You have to buy the vent collar separately though. So you can connect your exhaust hose or dryer hose to it because some vents on the roof are just for ventilation in your attic space. Them vents you can’t hook your exhaust too. Proper ventilation is key to saving money in your house. I’m going threw the same problem at the time. Make sure you never just vent your fan to your attic space that’s a no no. Also if your fan is anywhere by water make sure your fan is wired inline with a GFCI it’s just the way to do it. Hope this helps you out **Q: I have a 12 in wide metal roof and I need to put a vent to vent out heat from the roof . Would the brown 636 work to do this.** A: It could probably be made to work, but that's not what this vent cap was intended for. It has a flap in it that is normally closed, that would have to be removed. (This vent cap is normally used for a bathroom vent fan that will push the flap open when the fan is running.) Depending upon the style of metal roof you have, it may be difficult to get this vent cap sealed properly. This one is designed to have its upper flashing edge under shingles. If your "12 in wide metal" is in horizontal rows, that may work. Also, this vent cap is significantly smaller than what it normally used for roof vents. It will probably take three times as many of these as regular roof vents, to vent a given area of roof. In short, yes it probably could be used for a roof vent, but it would not be ideal. **Q: Can the damper get frozen shut in the winter?** A: It's possible, but not too likely. And even if it does, when the bath fan is turned on there will probably be enough air leakage that it would thaw the flap in a minute or two. **Q: pulled flapper, replaced cheesy strip at front of flap and added to other three sides with 3/16 thick, 3/8 wide foam weather strip. is this ok?** A: Maybe ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great roof vent! *by on Reviewed in the United States August 1, 2026* Used this to install a new bathroom fan. Way better price than a box store. Worked perfectly. No complaints! ### ⭐⭐⭐⭐⭐ A fantastic buy! *by on Reviewed in the United States April 28, 2025* The Broan-NuTone 636 Roof Vent Cap is excellent! It fits perfectly on 3" and 4" ducts and provides strong, durable protection against weather. Installation was straightforward, and the black finish looks sleek. Great for bathroom ventilation—no leaks or issues so far. Highly recommend for reliable performance and quality construction. A fantastic buy! ### ⭐⭐⭐⭐⭐ Well made *by on Reviewed in the United States February 6, 2026* I was a bit skeptical as to exactly what I was getting but this turned out to be a very well made product . I was pleasantly surprised. I only need it to vent hot air from an 'A' roof that gets very hot in the summer Highly recommended ## Frequently Bought Together - Broan-NuTone 636 Steel Roof Vent Cap for 3" and 4" Round Duct, For Bathroom Ventilation Fans, Black - Broan-NuTone 634M Steel Roof Cap for 6" Round Duct, for Range Hoods, LoSone Fans, and Bath Ventilation Fans, Black - Broan-NuTone DC4 Roof Vent Cap Duct Collar, No Size, No Color --- ## 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.us/products/1889812-636-steel-roof-vent-cap-for-3-and-4-round](https://www.desertcart.us/products/1889812-636-steel-roof-vent-cap-for-3-and-4-round) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-08-22*