# Non-combustible rainscreen drainage mat **URL:** \ **Category:** Archive - Product Discussions #6\ **Created:** [January 31, 2017, 9:32pm UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187 "2017-01-31T21:32:28Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![vivianvolz](https://yyz1.discourse-cdn.com/flex047/user_avatar/forum.4specs.com/vivianvolz/32/231_2.png) [@vivianvolz](https://forum.4specs.com/u/vivianvolz)\ **Post date:** [January 31, 2017, 9:32pm UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/1 "2017-01-31T21:32:28Z")
I’m looking for a non-combustible drainage plane that is noncombustible per ASTM E136. A mat would be great, since it’s behind stucco and needs a fabric to keep the plaster out of the drainage plane. Seems like all these tangled-mesh plastic products with the filter fabric have a decent flame spread (less than 50) but aren’t tested per ASTM E136. I’m trying to take advantage of the exception in IBC 2015/CBC 2016 1403.5 that allows a tall wall assembly not to need an NFPA 285 test if the air barrier is the only combustible component in the wall. Whatcha got? Name names, please! ---
**Author:** ![ecwhitby](https://avatars.discourse-cdn.com/v4/letter/e/94ad74/32.png) [@ecwhitby](https://forum.4specs.com/u/ecwhitby)\ **Post date:** [February 2, 2017, 3:14pm UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/2 "2017-02-02T15:14:16Z")
Perhaps you could use metal lath, installed on vertical hat channels. Galvanized or stainless steel of course. ---
**Author:** ![David\_Axt](https://yyz1.discourse-cdn.com/flex047/user_avatar/forum.4specs.com/david_axt/32/24_2.png) [@David\_Axt](https://forum.4specs.com/u/David_Axt)\ **Post date:** [February 3, 2017, 6:41pm UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/3 "2017-02-03T18:41:46Z")
Vivian, I highly recommend The Stucco Resource Guide from the Northwest Wall and Ceiling Bureau. It is a great reference for technical data and details for stucco. [http://www.nwcb.org/stucco-resource-guide.html](http://www.nwcb.org/stucco-resource-guide.html) ---
**Author:** ![vivianvolz](https://yyz1.discourse-cdn.com/flex047/user_avatar/forum.4specs.com/vivianvolz/32/231_2.png) [@vivianvolz](https://forum.4specs.com/u/vivianvolz)\ **Post date:** [February 7, 2017, 12:01am UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/4 "2017-02-07T00:01:07Z")
I did find a few lath-like solutions and spacer solutions galore. And I had one manufacturer (in keeping with my request to name names, it’s Stuc-O-Flex) point out that the drainage plane could reasonably be considered part of the air barrier, and thus be allowed to be combustible. I haven’t tried that approach yet with the code official, in the hopes of finding a true tested solution. David, it’s a brand new exception in the code (for us in California, anyway), so since the stucco guide is $95 and I just bought its competitor for $89 from WWCCA, do you mind taking a look at it and seeing if it contains answers to my question? (The WWCCA book is not helpful on this topic, but has terrific photos of plaster textures.) ---
**Author:** ![vivianvolz](https://yyz1.discourse-cdn.com/flex047/user_avatar/forum.4specs.com/vivianvolz/32/231_2.png) [@vivianvolz](https://forum.4specs.com/u/vivianvolz)\ **Post date:** [February 8, 2017, 12:45am UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/5 "2017-02-08T00:45:06Z")
I have officially given up trying to find a non-combustible mesh drainage plane. If the owner team decides they’re comfortable calling it part of the weather barrier, I will report back how that goes. ---
**Author:** ![guest](https://avatars.discourse-cdn.com/v4/letter/g/8dc957/32.png) [@guest](https://forum.4specs.com/u/guest)\ **Post date:** [February 8, 2017, 4:24pm UTC](https://forum.4specs.com/t/non-combustible-rainscreen-drainage-mat/3187/6 "2017-02-08T16:24:17Z")
Vivian, would something like Tyvek’s Stucco Wrap work? It is a weather barrier designed to act as a drainage plane. “DuPont Tyvek StuccoWrap WRB has an engineered, grooved surface that is designed to be installed as a drainage plane behind stucco facades and EIFS systems.” [http://www.dupont.com/products-and-services/construction-materials/building-envelope-systems/brands/water-barrier-systems/products/tyvek-stuccowrap.html](http://www.dupont.com/products-and-services/construction-materials/building-envelope-systems/brands/water-barrier-systems/products/tyvek-stuccowrap.html)