If you are working on a project that involves phone lines, we would like to ask you to take a closer look at the firestop installation for these materials.
This next blog series is going to discuss a few challenges we have found with firestopping phone and data lines and we are going to start our discussion in wood framed buildings, despite the fact that much of this information is relevant to other construction types. Your phone/date teams such as Verizon, Comcast and the rest of them are likely creating a liability on your project when they run their data and phone lines. To those of you who think that I should inform these big companies, I have tried unsuccessfully to find the right person to speak with. The only solution I can think of now is to let the rest of you know about this issue and hope that you can at least make a difference on your projects.
These phone and data installers use two different materials from what I have seen. If you see something different in your area, please let me know. One is the white plastic HDPE lines that are relatively small, maybe 5/8” OD and may be run as single lines or may be run as bundles. They cause an array of issues. The first of which there is that only ONE firestop manufacturer that I can find who has LISTED detail for these microducts . That means that if your installers are using a different manufacturer, they are creating a liability because they are not using the materials as they have been designed and tested. It could be worse than that. They could be installing something that we know WON’T work in a fire scenario.
This blog series will address the following issues. First, we will discuss HDPE, microduct through wood floor ceiling assemblies as a single line. Next, we will look at what to do when they are in bundles through floor ceiling assemblies. The UL nomenclature for both of these applications is FC 2000. After that, we will look at gypsum walls. These are WL 2000 series details. Then we will discuss concrete assemblies. We will group CAJ, FA and WJ details in this same discussion and finally we will look at FE details which are similar to FC details except that FC is wood framed, where there is a plywood floor on top of wood trusses and drywall ceiling to complete the rated assembly. FE details are fluted metal deck topped with concrete sitting on metal trusses and then the ceiling on the underside of the assembly is part of the rated floor ceiling assembly. It is similar to FC, but due to the metal framing there are some unique differences that we will discuss as a separate section that, knowing me, will lead us to a whole new discussion about problems with FE assemblies. Here is a common rated floor assembly in case there is any confusion regarding what type of assembly we are talking about.
If we don’t get sidetracked before we get to the end, we may address ENT. This is Electrical Non-Metallic Tubing or what I have heard in the field called innerduct. It’s the orange corrugated flexible lines that are between one and one and a half inches in diameter. They have very thin walls and the corrugation gives the material flexibility and strength while keeping it light weight for the installers. This is a different material with different fire dynamics so of course it needs a different assembly.
One thing to know before we launch into these individual discussions, is this. Several firestop manufactures’, when asked for a detail for microduct have sent me details for ENT that specifically list PVC. HDPE has very different fire dynamics than PVC. If you were to read about it you may see that it requires a higher melting point than other PE plastics. Polyethylene, when compared to PVC will typically melt much faster. It is true that HDPE requires higher melting temperatures than other PE plastics but let’s put this into the reference of the ASTM E814 fire test. If you have been following this blog for a while, or involved in the industry, you will already be familiar with the time temperature curve. For this discussion we are going to look at it in reference to plastic pipes.
If we were to say that all of these typical plastics, including the CPVC used for sprinkler pipes will melt between 200F and 500F. The difference seems inconsequential when you consider that a one hour fire test will reach 1700F at the one hour mark and 1000F at the 5 minute mark. The difference between 200F and 500F seems inconsequential for this discussion, but the lower temperature plastics will often need a much more aggressive intumescent material to survive the ASTM E814 test. The only way to know what is needed for different applications is to check the third party test details. If you have any questions about a specific installation feel free to reach out for help.
When installing (or inspecting) plastic pipe installations the annular space the type of firestop material used and the type of plastic are all critical to ensuring the installation will perform as expected in a fire scenario. This discussion is not breaking down all those details. We are only focusing on ensuring that the type of plastic you have in the field matches the tested and listed detail. This is critical.
Check in on the next blog to see if your team is installing these data and phone lines correctly. We will break each of these discussions into three parts we mentioned earlier. We will start with the present field conditions we see. We will talk about the problem with that field condition and then we will discuss some solutions to consider. See you again soon. Until then, keep learning and keep making the buildings you are involved with safer.
Please check in for the entire series if you are using this material we want to help ensure it is firestopped right. If we can help with anything please give us a call.
We have blogged about plastic sprinkler pipes in the past but it’s so easy to get it wrong, that it warrants more information. As always, we have a story for you, but before we get to the story however please know that despite the fact that we are mentioning two manufacturers in the story, we are NOT saying one is better than the other or showing favorites in any way. These are just the facts of the story as it played out in the field for us and could for you as well.
I was doing special inspection on a wood framed project where the installer was using STI’s WF300. This is a great material for wood framed projects. It’s cost effective and relatively versatile in wood framed construction. We had our submittals showing the listed details for each application they were using in the field. Towards the end of the project the contractor had the laborers make a supply run to finish up the final touches on the firestop. This is where our problem began.
After being in the industry for 20 years, a slight change in that iron oxide red causes one to take a closer look. The plastic sprinkler pipes came through a rated assembly and was firestopped like the other penetrations, but there was a slight difference in the material they used. Just barely enough to warrant a closer look, but just enough to see clearly, they used something different. Further discussion made the problem clear and rather serious.
Allow me to change gears for a moment and then we will bring these two discussions full circle.
CPVC pipes such as Flowguard, BlazeMaster, Corzan and TempRite are developed by Lubrizol. They have two great websites that you should keep handy if you work with projects that use plastic sprinkler pipes or CPVC.
This first one lists materials that have been tested and found to be compatible with these types of plastics.
This next one lists materials that are found to be incompatible. There are a handful of firestop products on this list. One of them is 3M’s CP25WB. Again, this is not a bad product, it is just not the appropriate material in this scenario and there are plenty of other materials on the list, so 3M is not alone. The problem is that the chemical compatibility can cause splits or holes in the plastic pipes. If the sprinkler pipes don’t start to leak before the sprinklers are needed, the change in pressure when the sprinklers engage will certainly test any system and one with small holes could impact water pressure and prevent sprinkler systems from performing as designed.
Here is another blog post on this topic in case you would like additional information.
This news article is just one of several that touch on the topic of compatibility issues.
So now that you have a little more background let’s get back to the story we started, back to our jobsite. The contractor sent a laborer to a local shop to get the firestop material they needed to finish the job. Certainly, on the shelf there was CP25WB and IC15WB. CP is red and IC is yellow. They knew that if they showed up on site installing yellow firestop that the inspector (aka me) would ask them for new firestop submittals for this new and different material, so they went with what seemed like the easy route.
When we returned for the inspection and noticed a slight difference in the color and started asking questions the installers brought the tube of the material they had used. They used CP on the CPVC pipes and as you can see from the links we shared; this creates a problem. Now that the materials have made contact the compatibility issue is present and you can’t just remove the sealant and replace it with the right red stuff or even the yellow stuff. You have to replace that section of pipe. If you don’t believe me, check with the various manufacturers or even your own corporate legal or risk management team.
It is not clear what this contractor chose to do, but after being informed of the issue and the potential severity we hope they chose to do the right thing.
Welcome back to the series where we talk about “stuff we see wrong in the field.” This blog is going to discuss a few challenges we have found with PEX lines in wood framed buildings. If you are working on a concrete project that is using PEX, you should still read this just in case you are making the same mistake. We hope it is useful.
Here is our field condition:
The plumber drilled a hole through the two by fours that are sitting on the plywood floor to frame the wall that will be built. The hole is less than ½” larger than the pex line they are running. This gives them just enough space for the bracket the plumber is using. In the field, they call them mickey mouse ears. I’m not sure what they call them in your area but here is an example of one.
The firestop installer simply smeared firestop around the pex line and covered the mickey mouse ears. It wasn’t until we did destructive testing that we discovered the problem. So, if you are an inspector on a project that is not going to require special inspection, please walk the site before the firestop is installed to see if they are using these things. If they are, you may want to ask a few questions. If you need some help give us a call.
The mickey mouse ears use up all the annular space that you need for the installation of the firestop material. With plastic pipes you typically need to have an intumescent firestop material. This is one that is capable of expanding to fill the void created when the plastic pipe melts away during a fire. The intumescent material can close down the opening and prevent the passage of fire.
Intumescent materials act like most things in nature. That is to say that they move in the area of least resistance. That means if it is sitting on the top of the two by four and adjacent to the pex pipe, when it starts to expand its going to move in the area of least resistance. This will be away from the pipe.
For this reason, the intumescent material needs to be forced into the opening so that the two by four, the concrete or the drywall can contain the sealant as it expands so it is forced into the center of the opening. This enables the material to close down the opening as the plastic pipe softens in a fire and yields to the expanding intumescent sealant.
This is also why, when a plastic pipe touches the side of the opening, its required to have a bead of sealant, which is a build-up of material along the edge of the penetrant and against the rated assembly.
However, when a detail allows for annular space to be 0-1” for example it does not mean that you can have 0 annular space all the way around the opening. If this is allowed the detail should say “continual point contact” and few details do.
There are a few ways to handle this. One would be to not use the Mickey Mouse ears. Another would be to install the firestop first and then force the sealant into the opening as you push the bracket into place. Inspection would be difficult and ensuring proper sealant depth during installation would be imperative.
If you run into this issue, let us know how you handle it.
Thanks for taking the time to read this. We hope you found it valuable. If you did, please leave comments and let us know what other topics you would like to see us address in future blogs. Share this with anyone who can benefit and keep learning. Check back for more in this blog series as we discuss other field issues we encounter.
Firestopping Soda Lines-
This blog series is going to highlight some issues we have seen on projects that are easily overlooked if you are moving too fast, or if you are new in the game. It is our hope that by sharing these things with you and your team that you can avoid the mistakes. If you have any questions let us know. Especially if you have suggestions for supporting the rest of the people out there who want to do firestop right, then please share your ideas. Thanks for taking the time to learn.
If you are on a project such as a high-rise office or maybe a hotel that will have a bar or restaurant, then there is a good chance you will have soda lines in your project and they likely won’t get installed until towards the end. The conduits look like any electrical conduit so it’s easy to understand how someone inexperienced would allow this conduit to be firestopped with a standard detail that allows for steel, cast iron, electrical conduit as the listed type of metallic penetrating items. This would be a mistake. The fire dynamics are going to be different for metal than they will be fore steel and there is a chance that the firestop requirements will be different as well. If they are different, then the protection method could be different as well.
Then there is the liability. If you firestop it with a detail for steel and something goes wrong, then you are potentially liable for this mistake if you installed this or supervised the installation in any way.
Is there a difference, really?
YES, there is a difference between these two metals. Consider this. Melting point of steel is 2750F. Melting point of aluminum is 1221F. If you have been following this blog, then you may remember the “time temperature curve” (see below). This shows the temperature inside the furnace, for example at the 10-minute mark the temperature inside the furnace will be 1300F.
While I have not witnessed a test with aluminium pipe, I have seen photos and videos of the aluminum transoms and mullions of exterior facades and I have seen them drooping and deformed.
Is it really going to be firestopped that differently?
Here is a detail that allows a max 8” diameter aluminum pipe but it requires a minimum annular space of ½” and it needs a full inch of sealant. A typical steel detail would only need ½” or in some cases ¼” of sealant and would allow the pipe to touch the edge of the opening. http://productspec.ul.com/document.php?id=XHEZ.C-AJ-1342 or this one that allows a 10” aluminum pipe but requires wrap strip at the top and bottom of a floor assembly. If it’s a smaller pipe the parameters are a bit more familiar. These two details and the differences between the standard metal pipes you are likely familiar with should serve as a reminder to look at these details closer if they are on your project. http://productspec.ul.com/document.php?id=XHEZ.C-AJ-1112
How do I tell the difference?
First thing to do is to ask the question. The vendor installing the bar or restaurant equipment would be the first place I would go.
Second thing is to touch a magnet to the pipe. If you wonder whether or not it’s steel, a magnet will tell you. It won’t be attracted to aluminum, so it won’t stick to it. But be careful because this is not a guarantee that you are dealing with aluminum, because magnets may not stick to stainless steel. So, this brings you back to asking questions of the right people on the team.
Third thing to do is to keep your eyes open. You can see in the photo that its clearly marked on the floor SODA. After today, that should be a red flag for you to stop and ask questions before anyone firestops this.
If all you remember, is to ask questions whenever there is a restaurant or bar, then the time we took to write this was well spent. If you have any questions don’t hesitate to contact us. We are happy to help if we are able.
If you want to get firestop right, you can start by tackling the things in this article. There is a LOT in here to digest and each item warrants an article on its own, but this is great information to apply to your work if you are in any way involved in a project that needs firestop. Great job Eirene!
If you have any questions, email me and I will get you answers and may even do a blog post to clarify your question so others can learn from it as well.
Our last blog post discussed clearance requirements for sprinkler pipes when you are working in a seismic zone. The NFPA and the damper manufacturers use the phrase clearance. The firestop industry uses the term annular spaceand defines it as the distance from the outside edge of the penetrating item to the inside edge of the opening in the rated assembly.
Firestop applications often refer to a minimum and maximum annular space. This is because most of the times the pipes are not centered in the opening. This is not going to cause a problem with most applications, but when we look at the NFPA requirements discussed in the last post we used the example of an 8” sprinkler main that would require a 12” opening.
If the pipe is centered in the opening the firestop detail will require roughly 2” annular space. This is not typically going to be an issue, but when reviewing the firestop submittals you need to make sure the annular space of the firestop details will conform with this code requirement. But that is not realistic to have the pipe centered in the opening all the time. If you want to prepare for the worst-case scenario, which would be the pipe slammed all the way to one side of the opening then you have to be sure your firestop submittals allow for this.
If the pipe is completely askew you may have as much as just shy of 4” of annular space o contend with. Well, really it will be less because even if you have an 8” pipe and a 12” opening the outside diameter of an 8” steel pipe is going to be close to 8-1/4” so that would make the maximum annular space around 3-3/4.
Most firestop manufacturers have fantastic websites to help you find the details you need or you can call them directly and talk to their tech team for additional support.
When you are conducting your firestop submittal review you need to be sure that your firestop details can meet this requirement, or that you have seismic couplers on both sides of your rated walls and floors and any “non-frangible” substrate.
Two other things to look for when comparing the firestop detail to the field condition:
- Sleeve: Did the use a thin gauge tin sleeve? Is that allowed by the detail? Firestop details often list a sleeve as optional, but some don’t allow (sleeve is not listed) or some require it. If a sleeve is allowed or required check to be sure the gauge in your paperwork matches what they used in the field. The fire dynamics of a thin gauge sleeve will be different from that of a heavier gauge sleeve so they may need to be treated differently. So, to make this simple for you just remember, you need to look for 2 things:
- Is the sleeve allowed or possibly required?
- Does the gauge match?
- Support Bracket: If firestop is smeared all over the bracket that means that it was in place when the firestop was installed. That seems basic but it means that the firestop may not be installed properly. Check back on our next post for more details on this.
If you have problems or questions, don’t hesitate to contact us for help as well.