I hope you liked the last post, that was just a warm up as we bring you to this new document by the International Firestop Council. Its 7 pages and packed with great information and I will expound on it in the next blog series because this document does a great job of explaining what needs to be done, it doesn’t tel you the common things installers do wrong, or things they miss. So please start with a read of this document and then come back and we expound on this a bit further in the next few series of posts. IFC Membrane Penetrations
There are a few other membrane penetrations to consider depending on the type of construction you are looking at- so while this is not an exhaustive list it adds to the one in the article because you need to keep an eye out for any of these items that are not surface mounted. If they are recessed or semi-recessed in a rated wall then they are membrane penetrations. Please pay attention when looking at the following- fire hose cabinets, fire extinguisher cabinets, time clocks, elevator call boxes, IT control panels, electrical panels, shower diverter valves or anything that punches through one side of a rated wall. So have a read of the IFC document and check back for our next blog as we take the discussion a little further.
In the meantime, let us know if you have any questions or concerns.
See you next time!
Firestop applications that only breach one side of a rated assembly are called membrane penetrations. They are often poorly reviewed. This is true of wall penetrations but even more true of floor penetrations. If you have been following this blog for a while, you know we are big on offering information in multi-part series and this topic will be NO DIFFERENT. We will start with two different documents one from UL and the other from the IFC and we will build on those documents in hopes of helping you see what to look for on job sites. This doesn’t matter if you are an AHJ part of a QA/QC team or a special inspector. You need to know the information in this series to help increase the level of life safety and reduce liability. So please read and challenge yourself to apply this information on your projects.
We will start you on this UL document.
Here are a few key takeaways-
Plastic Electrical outlets-
- Look for the UL logo
- be sure it is listed for use in a rated floor/wall/ceiling that it is installed in
- if you don’t find it, the box is not tested to be used in a fire rated assembly. You can’t just throw a putty pad on the non-rated boxes to fix the problem. It’s not that simple.
- Check the size of the boxes, because even if it is UL listed it can only be up to a certain size before it requires a putty pad, regardless of its proximity to any other boxes. Metal boxes cant exceed 16 sq in, plastic boxes may vary by manufacturer depending on what was tested (and what passes) so look at the paperwork
- When you are reading the firestop detail (because that’s everyones favorite thing to do RIGHT?!) pay attention to whether or not the application requires
- a metal cover plate
- a ball of putty inside the box (I have never seen anyone do this unless they get called out- and I rarely see people called out even when it is a requirement)
Metal Outlet Boxes-
- don’t assume that you can throw a putty pad on any sized box. Refer to the CLIV (the tested detail) for the limitations
- depth of box is a big deal. We will get into this in a future discussion, but if you recall our conversation about shaft wall assemblies it is related too that. If you didn’t see that you can review here.
- Again if you install a box in a wall/floor/ceiling you have to be sure it is rated for that use. If it is rated for use in a wall, it can automatically be used in a ceiling or floor.
I know the firestop details for putty pads are cumbersome and painfully boring so if you have any questions, ask your electrician or your firestop installer for the CLIV document, email it to me and then let’s have a chat. I can help get you on the right track to ensure these are done right.
Have you ever searched for a UL detail on their website? The original website required a special degree in UL nomenclature. Then they made some huge changes and it got much easier. They have made some new changes that you are likely to enjoy even more.
That is not to say you will specifically enjoy the search for the perfect rated detail, but it certainly will be easier. Plus the old site will be retired in a week, so you won’t have any other options.
If you haven’t already, please check out the new site. You may even want to bookmark it.
You have all heard the whole, “What Happens in Vegas, Stays in Vegas” line from way back when? Even before that, you have likely heard of the fire at the MGM Grand in 1980 where 85 people died and over 600 were injured. Well, the changes made to the building department in the years since, are lessons that shouldn’t be part of what stays in Vegas. They should spread to other jurisdictions and today I will discuss just one of these points, since it is in line with the discussion about patching rated walls.
Clark County Building Department covers the Las Vegas Strip and they take life safety seriously. I know you all do, but they take it to a different level and one that some of you may want to consider taking a closer look at. They actually have a FIELD INSPECTION GUIDELINE that tells, not only field inspectors, but also builders and facilities maintenance teams how they should be repairing walls if they want to pass inspections.
Have a look at it and let me know what you think. Are you doing something similar to this? If you aren’t do you think it might be time to revisit how patches are made and if so, what do you think should change? If you have any questions, don’t hesitate to reach out to us. If we can help we are happy to.
Thanks for the great response on the last post related to patching rated walls. There is a lot more I want to share with you in the future but I have to find time to create the content. I heard back from so many of you that you liked the post I thought I would at least share some more information that is already created so you can take it a step further.
Three key reasons the California patch will fail in a fire test scenario:
- It will fail at the hose stream test. For more information on this, check out this series we did a while back on Hose Stream and imagine that patch, or any patch you accept being able to pass the hose stream test as it is described in these posts from 2016. https://halpertlifesafety.com/firestop-inspection-f-rating-hose-stream/
- It will fail when you try to achieve the T rating- which is required of all rated walls and floors. There is a bit of information in this article here.
- As the drywall patch (or GOD FORBID drywall tape and mud excuse for a patch) heats up in a fire it will shrink. As the existing wall dries up it shrinks as well. When this happens the gap between the existing wall and the patch material grows. This makes it easier for the patch to dislodge during the hose stream test and this gap will allow hot gasses through and that is how the T rating segment of the test will fail.
So, the next time you see a patch in a rated wall, please take a second look to ensure it is not creating a liability for your project and the community of people who will live work and play in the building when you are gone.
As always, thanks for taking the time to learn more about the industry I love. If we can help you on any project you are working on, don’t hesitate to reach out to us.
I have seen some creative ways of patching walls. Some are UGLY and some are invisible. Here is a great video of how to make an invisible patch BUT you can’t do this on a fire rated wall. This California patch or butterfly patch will not survive the rigors of the ASTM E119 fire test.
If you have been in one of our training classes where we discuss how rated assemblies are tested then you know the two biggest ways bad patch assemblies may fail are either because the fail at the hose stream test segment or even before that as the wall tries to maintain a T rating and the growing gap between the original wall and the patch material shrinks as the fire consumes its mass and the growing gap allows for hot gas to pass through and it will fail at this point.
So, how do you properly patch a rated wall? Check out this guide from US Gypsum association to see if you are doing it right. USGyp repair of wall
If you are looking at a repair of a one hour wall that is relatively easy. Properly patching a two hour wall is a whole different story all together. If you have any questions don’t hesitate to reach out to us. We are happy to help if we are able.
What if there were a terrorist attack on one of your projects? If you are a builder or a developer or even part of the AEC team you can assume a day in court, but did you know you can protect against the outcome and insulate your firm from the litigation? This article will help explain how.
If you have other questions you can reach us here.
Thank you to CONSTRUCTION EXECUTIVE for understanding the value of this discussion for both building owners and builders alike.
We will be at the Tri-State AIA conference tomorrow to discuss this very topic.
If you are looking for more information on tall timber construction check out this slide deck (yes another offering from UL/FDNY/IAFF forum back in January) This presentation shows more information about how the tests were conducted, discusses a handful of projects and then building code information. This presentation was delivered by Cleveland’s former Battalion Chief, Sean DeCrane and you are missing a lot just getting a peek, but even this peek offers a lot of valuable information if you are interested in learning more check it out.
Thank you to UL for allowing me to share this information.
Questions about CLT?
Here is another presentation from the UL/FDNY/IAFF forum Meeting the Challenges of the Future Built Environment at the New York City Fire Training Academy Randall’s Island, New York City. This presentation was delivered by Raymond O’Brocki and discussed things such as the ICC Ad Hoc Committee on Tall Wood Buildings, their objectives, the tests and their findings. There is some great information in this slide deck and it was even more valuable when it was presented in person.
Thank you to UL for allowing me to share this information.
Tall Timber buildings are now a code requirement. How is this going to impact your jurisdiction? There will be a number of variables and one certainly should be the opinion of the men and women who will be responsible for fighting fires in such structures. In honor of these individuals here is a FIREHOUSE article on the topic so you can see what fire fighters think about tall timber construction.