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.
Thanks for joining us yet again for a continued discussion about firestopping shaft wall assemblies. The discussion today will continue along the question asked during the start of this never-ending series of “how do you properly firestop penetrations in a shaft wall”. If you remember a few weeks ago I told you, that for the sake of this discussion let’s say we are talking about a mechanical shaft so the penetrations might be 1) bare metal pipe 2) plastic pipe 5) insulated 7) ductwork. If you think my numbers are not in the right order please look at this post so you understand why the numbers are in perfect order. Looking at these different penetrations will help you maneuver through firestop submittals much faster, so please become familiar with the UL nomenclature.
The last few posts were talking about the bare metal pipes- aka the 1000 series firestop details. Today we will talk about the 2000 series details, which as you know are the plastic pipes. Plastic pipes provide a whole array of challenges. This means they are easy to do wrong. They are combustible and depending on the chemical composition of the material they will melt between 200F and 500F. If you want to know more about how they are tested please check out the past post (be sure to read the amendment before watching the video). https://halpertlifesafety.com/how-rated-assemblies-are-tested/
First let’s tackle the gypsum wall applications. It will be critical that this be done in stages. For this discussion, we are going to look at a Hilti detail. The detail we are going to look at for this application is WL 2217.
Item 1: It allows for a shaft wall with 1-5/8” studs.
Item 2: It allows for maximum 4” PVC or CPVC. I spoke with a contractor one time who said, “It lists plastic pipe, so its fine.” NOOO. This is not true. When you are dealing with plastic pipes there is SO MUCH to look at.
- the size
- the material
- it must list the proper material if it only lists PVC then you can not use CPVC or any other type of plastic, pex, polypropylene, sprinkler pipes and the list goes on…and on….
- The right gauge or thickness- for example the plastic pipes used for IT are not the same as what is listed above, even if they are made of PVC hey are not likely the right schedule.
- If your field material is cellular core, you need to be sure the submitted detail allows that material to be used.
- If the submitted detail only lists closed or supply lines you can not use that detail for a vent or drain line.
- If your submitted detail is for a specific brand name of pipe, you can only use that detail with that brand of pipe. For example if the detail calls for a polypropylene pipe called Aquatherm, you may not use that detail with a different manufacturer.
- The annular space MUST be adhered to and in some cases, it can be very restrictive. The larger the pipe, the more critical the annular space will be, except for polypropylene pipes, which are really combustible and require unique applications even on smaller pipes. By unique I mean more restrictive annular space and aluminium foil tape around the pipe prior to the installation of the collar.
That is a lot to take in and we have not even gotten to the firestop installation yet. I am going to let you sit on this and throw any questions my way. We will tackle the firestop installation next week, because there is a lot to share with you on that as well.
So have a great week, be productive and keep an eye out in the field for all of your plastic pipe installations. Next week we will go over what to verify when you are looking at the firestop installations. For now, the next time you are looking at a firestop submittal that includes plastic pipes, you now know there is a LOT to deal with.
If you want an extra set of eyes to look over a firestop submittal on your project, please give us a call. We are offering free review and follow up phone call for your project. You just have to send us your firestop submittals and we can schedule a time for a phone conference.
It’s completely complimentary because we want to shed some light on how to do this right. There is of course one catch. This offer is only for contractors who have a desire to do things the right way. If you want to cut corners, you don’t want us on your team.
If you want to build a strong team, we promise after just one project with us, your team will be stronger on their next project. We have been bloging on firestop since 2015. Wee have been sharing information, in hopes of improving this industry. If you have a team of people who want to do this right, we guarantee that after one project with us they will be better able to:
- identify problems before they are built
- know how to resolve common problems
- they will have a list of things to look out for (yes a physical list to check off- but that is only for our clients)
- understand the codes related to firestop
- know the requirements of special inspection
- understand the handful of standards related to firestop
- understand how to troubleshoot common problems
- when to call for help, and who to call (it’s not always HLS)
If you need help, give us a call. If you want to be sure you are heading in the right direction we can help you with that also. We hope to hear from you if we can help. We are offering a complimentary review for the month of July.
Welcome back everyone. On Monday I left you with a bit of a challenge. I asked you if you could use WL1222 for a firestop application for a metal pipe going through a gypsum shaft wall. Then, I told you that the answer to that first question was NOPE, but I asked you to look closer at the detail to find the reason, and then I LEFT YOU.
The suspense is over, keep reading and you will find not only why you can’t use that detail, but we will share a detail that is applicable and a few cautions about the proper use of this detail.
Were you able to identify WHY you can’t use the WL1222 for a shaft wall application? If not, look at the detail once more, but this time focus on item 1A. Please click on the link above and open the detail so you can look at it.
Did you find the answer this time?
How many shaft wall assemblies have a stud that is 3-1/2” wide?
If you are thinking that the gap doesn’t matter, you need to tune in to a future blog post about T ratings. That discussion will take me into several different directions; so, I will side bar that discussion for a later date, but hopefully some time this year.
For now let’s just say that if your field conditions don’t match your paperwork then you are non-conformant. If you are non-conformant then you are creating a position of liability for your company and whatever company you are working for regardless of whether you are an installer, inspector, GC or owners representative.
For now, let’s get back to identifying the right solution. In this case, our contractor is using STI firestop. We know this because item 3 of WL1222 lists LCI and also because the firestop detail has the STI logo on it. Again, I don’t have a favorite firestop manufacturer. I have favorite sales people and favorite products but not a single favorite manufacturer. My stance is, if they have the tested and listed details to support whatever project I am working on, then they are good for my project! Even if I am stuck with a sales guy I don’t like, I still have resources within the various companies to get what I need. That said, it has been a while since I have run into a sales person who has not been capable, qualified, professional and helpful. They are out there, but I have been lucky enough to not run into them.
Since our installer is using STI, let’s try to stick with this manufacturer as we look for a detail. In this case when we go to their website, or contact the sale rep, the search for me ended with WL1251. Please click on the link and have a look at this detail. Take a moment to think about the things you want to be sure the installer does right.
Item 1 in this detail allows for C-H or C-T studs that are min 2-1/2” wide and 1-1/2” deep (item 1A). Item 1C offers a caution that the circular cut out cannot be larger than 10”.
Item 2 notes a sleeve. It does not say OPTIONAL so this means the sleeve is a requirement. If you don’t have one of these fun toys I suggest you get one because it will help you verify that the sheet metal is the proper gauge. This detail says you must have a min 30 gauge galvanized sheet metal sleeve.
Item 3 is the penetration and the annular space. Obviously a larger pipe or different type of pipe than what is listed will not be acceptable for use with this detail.
Item 4 is where you will find the information about how to install the firestop material and what is required
If you have a 6” pipe centered in an opening that is 3” larger than the pipe, you will be okay. However if you have an 8” pipe in the same scenario you would not be able to use this detail because in 1C it says the opening can’t be larger than 10”. This means that despite the fact that the detail allows for a max 2” annular space you cant have more than 1” all the way around if you have an 8” pipe.
- The sleeve is a requirement and not optional:
- If you don’t use a sleeve then the mineral wool and sealant will not stay in place during installation.
- If you tell me that the wall cavity is already filled with mineral wool so you don’t need the sleeve, then you are not thinking about what will happen in a fire scenario after the shaft liner has burned away and the mineral wool falls out along with the burnt gypsum board. The sleeve is a requirement for a reason, don’t let the installer skip this part.
- You need to ensure the gauge of the sleeve is accurate.
- The overlap on the sleeve needs to be 2” minimum in order for it to:
- Comply with the detail
- Be expected to maintain its integrity in a fire scenario when we remember the fire side of the wall is going to be gone as the fire rages
- The sleeve has to be long enough to be captured both by the shaft liner as well as the outer layers of the shaft wall. If it is too short you may have a problem in an actual fire scenario.
The only caution I have to share with you here is to be sure that the annular space is sufficient to allow for the installation of the mineral wool and the required sealant.
- If you are on a stick built project and the roofers are using 2pound density mineral wool on the roof, DO NOT ALLOW THIS TO BE USED FOR FIRESTOP. Installers may tell you, “it’s the same stuff….it’s rotten cotton” What they are missing is that the detail calls for a minimum 4pcf and I have yet to find a firestop detail that allows the use of 2pcf. It is probably fine for roofers, but it is not okay for firestoppers.
- If you have the chance to watch the installation, you need to be sure the mineral wool is recessed 1” into the wall so there is enough space to install the 1” of firestop sealant.
- If annular space is tight, installing 1” of sealant will be tough, if not impossible
That was with a gypsum wall. Below is a detail for a concrete or block wall. Take a look at the detail. What are the critical items you will verify if you are doing an inspection?
Is your head spinning yet? I will go easy on you with the next post. I promise! But if you are wondering how to firestop shaft applications, this is valuable information and we have only addressed the 1000 series details. These are the EASIEST details to deal with in our mechanical shaft application.
Thanks for reading this all the way to the end. I know there was a lot here. See you next time for more firestop information.
Welcome back to our discussion about firestopping shaft penetrations. With this post we are looking into the question of how do you properly firestop penetrations in a shaft wall assembly. First we will look at block wall assemblies. For the sake of this discussion we will assume these are shafts where we have no reasonable access to the inside of the shaft. Clearly, this will exclude stair shafts because in this condition typically we have access to the inside of the stairwell as well as the outside where the rooms would be located. For the sake of this discussion let’s say we are talking about a mechanical shaft so the penetrations might be 1) bare metal pipe 2) plastic pipe 5) insulated 7) ductwork. If you think my numbers are not in the right order please look at this post so you understand why the numbers are in perfect order. Looking at these different penetrations will help you maneuver through firestop submittals much faster, so please become familiar with the UL nomenclature.
If you have any questions or comments about the importance of knowing the nomenclature or asking for submittals feel free to contact me.
So let’s start with the easy stuff first. We know that wall applications have to be protected on both sides for the simple fact that we do not know which side of the wall the fire could start on. This makes it complicated because we don’t have access to both side of the wall in this case. If you have been following this blog post or if you have just now reviewed the link above, then you know the UL listed details we need to look at in the submittal will be either CAJ1000 or WJ1000 details.
My guess is, that what you need will be found in the WJ details because the CAJ details (as you know) can be used both for floor applications and for wall applications.
I’m a dinosaur in this industry (almost 20 years yup I’m a dinosaur- and yes I started when I was 12…LOL) and since I no longer work for a firestop manufacturer I don’t get updated on the new wiz bang details. I had to do a little digging to find you some examples of relatively new details that are perfect for this type of application.
You may have heard me say “I don’t have a favorite firestop manufacturer” so don’t think that because I should you use brand A that means they are the best. The best solution for any application is one with a third-party testing agency standing behind the applications as opposed to 1) the guy in the field “wingin’ it” 2) an engineering judgment.
That said, here is a perfect detail for your metal pipe through a concrete or block shaft wall: 3M’s WJ1108. This is not the only detail, other manufactures have a similar test, but since this tested system exists; I would suggest that jurisdictions not allow the use of an EJ for the simple fact that tested and listed details should trump EJ’s any day of the week for the simple fact that it that has not been tested.
Can you use this for a wall where you have access to both sides? Certainly, but whether you have access or you don’t, be very careful that this is installed properly. Both of these details require 1” of sealant. If you don’t have sufficient annular space then this installation will be difficult to properly install. If you are responsible for special inspection (or even the standard AHJ inspection) you may want to ask to be on site for several installations so you can be sure they install the mineral wool in a way that it is recessed 1” from the outside edge of the concrete. Clearly, if they don’t do this then they cannot install the required 1” depth of sealant.
Imagine you have ¼” annular space. Now, picture trying to install 1” of sealant in that space. It will be easy to make it look good when the installation is complete but it will be a challenge to do this right. As an inspector or part of the QC team, it’s your job to be sure its right. If you have any questions, contact us.
So, let ‘s move on to the gypsum shaft walls. In this case you know that we are looking at a WL1000 series detail. So first take a look at this detail, WL 1222
If we are going to install the firestop in stages as the drywall is installed, this means we will firestop the shaft liner before the outer layer of drywall goes up. So, does WL1222 work for this? Please take a moment to look at the detail and think about this question.
Have you looked at the detail and considered the question? If you think you can use this WL1222 for a shaft wall, I will tell you that you can’t. Go back to the detail and see if you can find out why? Tune in Wednesday to this blog post and I will share the answer with you.
Thanks for reading along so far. We have covered a lot in this series on shafts and hopefully you have been able to put some of this to use in the field. Next up, let’s look at what you should see when you are walking in the field looking at all that firestop stuff. Let’s put all this information to work for you.
First, you must have the firestop submittals if you are going to review (or install) firestop. The submittals should have UL listed details (or other third party testing agency – OPL or WH) that show the firestop requirements for all of these shaft applications. If you don’t have the details, you can’t properly evaluate the field installations.
Let’s walk a site together (You will need to use your imagination here). Say we are on the 5th floor of a hotel project. We are looking at a mechanical shaft. We have bare pipes and insulated pipes stubbing out of the wall to provide water to the bathroom. The shaft liner is up, but there is no firestop on the pipes. We go up to the 6th floor, the drywall is on the outer layer of all the shafts, but they have firestopped only about half of them. As you walk down the hall you see an area where they have not yet firestopped the penetrations into the shaft wall and you can see that they have not firestopped the shaft liner side. This is a problem. Firestop is required on both sides of a wall.
Let’s take the same scenario, but this time they did have firestop on the shaft liner side on the 6th floor. However, when you were on the 5th floor you noticed that the hole that was cut for the small, insulated copper pipe is just big enough to get the pipe and the insulation through. The insulation was almost touching the cut edge of the drywall all the way around. You don’t have firestop submittals for the project so you can’t tell that the detail requires annular space of 0-1/2” and what you have in your field condition is continual point contact.
If you don’t understand why this is a big deal please review the previous post here. If you are not familiar with how firestop is tested however I suggest you start here because this is the start of that series.
If you want to scream at me, “SHARRON YOU CAN’T USE ANY OLD WL DETAIL FOR A SHAFT WALL!!”, check out two posts from now when we address this. If you are not one of the people wanting to scream this at me, then definitely tune in because this is something that even some good contractors might miss.
Let’s get back to our field walk. The other thing you can’t see is that the firestop detail calls for 5/8” of firestop to be installed within the annular space. Since there is no annular space there is no way to achieve this depth requirement.
You have some problems.
The first problem is that you don’t have your firestop submittals, so you can’t reference what is required when you talk to the installer.
Second, they have created an installation that either cannot be firestopped properly or may require a more expensive solution. Of course, if we are talking about a gypsum wall, its not a big deal to make the opening larger (even though the contractor will fight you on this). If you are dealing with a concrete or block opening it will be more difficult for obvious reasons. However, if that opening is sleeved, it may not even be possible to fix.
Please also remember, if you are looking at a block wall, they will have to firestop both sides of the wall, or one side but do it two times. This is true both for joints and for through penetrations. If it is a shaft, you likely can’t get to the inside to check on the installations, so you may need to go to the bottom of the shaft before it is closed off to get a look, or you can conduct destructive testing to confirm that it was done right. Please also remember that the firestop details have to match the field installations. If they don’t, it is non-conformant and should not be allowed.
I thought this was going to be the last post on the topic. However, since the start of this series I have had a few people ask me some questions. The most prevalent is, “Okay so then HOW DO WE PROPERLY FIRESTOP SHAFT APPLICATIONS? “
We will address this in the next few blog posts. If you have any other questions, concerns or photos of WHAT DO WE DO WITH THIS? or IS THIS OKAY? Keep the feedback coming because I have a handful of issues to bring up for you once we complete this series.
Just for this post I have unleashed the code geek. Be scared (no…not really- its painless I promise). After we talk about the code we will discuss the things to look for to ensure your team is conforming to the code.
First let’s clear up the difference between an opening and a penetration. An opening (IBC 2015 713.7) is a hole with a purpose such as a door or a window. Doors and windows are tested to their own standards when acceptable for use in a rated assembly. Note that there is a difference between the test for a horizontal and a vertical opening protection the same way as there is a difference between firestop assemblies. You cannot use a horizontal and a vertical assembly interchangeably. For instance, if you have an access door that you want to put in a mechanical shaft you cannot use that same door in a rated horizontal assembly, unless it is tested for that specific application. Its all about fire dynamics; they simply are not the same in each orientation.
IBC 2015 713.8.1 is on prohibited penetrations and basically says that any penetration in a shaft has to have something to do with the purpose of that shaft.
Here are a few things I have seen.
I was looking at a set of plans with an architect. I asked him if his fire extinguisher cabinets were surface mounted or recessed. Turns out they were semi-recessed and they created a code violation because they were located in the shaft wall assemblies. He relocated them outside of the shaft and all was well with the world (or at least with the extinguisher cabinets).
I mentioned this scenario in a class and someone asked if they could just use a rated extinguisher box. It is a great question, because this is a common misconception. Please remember that the rated extinguisher box or hose box allows you to have a giant hole in a rated wall and not have a code violation, except if that wall is a shaft…then it’s a prohibited penetration. If you have a hose box or an extinguisher box in a rated wall it must be a rated box as well. This is a whole different blog for another time though because there are a whole series of issues we need to talk about related to membrane penetrations. We will get to that later though.
What other things should you look for that are common prohibited penetrations?
Interestingly enough, most of these are membrane penetrations like the extinguisher cabinet. It could be corridor lighting, the magnetic hold open apparatus on smoke doors, exit signs and anything along these lines. These are not serving the purpose of the shaft, so they are prohibited in the wall assembly. This needs to be addressed early in a project or it can create serious headaches down the road.
Now if these same membrane penetrations are in your means of egress, they are relevant to the means of egress and therefore not a code violation. A mechanical shaft has to have mechanical pipes coming out of it to service the floors, it may need to have an access door and all of that is okay provided you are using a rated access door. The mechanical shaft does not have to have corridor sconce lighting and if it does, then you, my friend have a code violation.
Heads up gang, that prohibited penetrations section that we talked about with shafts relates to means of egress as well. If you have a duct or pipe that runs from one side of the corridor to the other side and doesn’t service that area then you have a code violation. In this case, however, the exit sign, mag hold and corridor lighting would not be a code violation because those things presumably serve a purpose in the corridor.
In our next post we will do an imaginary field walk and talk about what we might see. If you would like some help pulling all of this together don’t hesitate to contact us so we can help on your project.
Thanks for reading along so far. We have covered a lot in this series on shafts and hopefully you have been able to put some of this to use in the field. Next up, let’s look at what you should see when you are walking in the field looking at all that firestop stuff. Let’s put all this information to work for you.
First, you need to have the firestop submittals that show the firestop requirements for all of these shaft applications. If you don’t have the details, you can’t properly evaluate the installations.
Let’s walk a site together (You will need to use your imagination here). Say we are on the 5th floor of a hotel project. We are looking at a mechanical shaft. We have bare pipes and insulated pipes stubbing out of the wall to provide water to the bathroom. The shaft liner is up, but there is no firestop on the pipes. We go up to the 6th floor, the drywall is on the outer layer of all the shafts, but they have firestopped only about half of them. As you walk down the hall you see an area where they have not yet firestopped the penetrations into the shaft wall and you can see that they have not firestopped the shaft liner side. This is a problem. Firestop is required on both sides of a wall, even a shaft wall.
Let’s take the same scenario, but this time they did have firestop on the shaft liner side on the 6th floor. However, when you were on the 5th floor you noticed that the hole that was cut for the small insulated copper pipe is just big enough to get the pipe and the insulation through. The insulation was almost touching the cut edge of the drywall all the way around. You don’t have firestop submittals for the project so you can’t tell that the detail requires annular space of 0-1/2” and what you have in your field condition is continual point contact. The other thing you can’t see is that the firestop detail calls for 5/8” of firestop in the annular space. Since there is no annular space there is no way to achieve this depth requirement. You have some problems. The first problem is that you don’t have your firestop submittals so you can’t reference what is required when you talk to the installer. Second, they have created an installation that can not be finished correctly. Remember those blogs where we talked about continual point contact and the importance of proper annular space?
Please also remember, if you are looking at a block wall, they will have to firestop both sides of the wall, or one side but do it two times. This is true both for joints and for through penetrations. If it is a shaft, you likely can’t get to the inside to check on the installations so you may need to go to the bottom of the shaft before it is closed off to get a look, or you can conduct destructive testing to confirm that it was done right. Please also remember that the firestop details have to match the field installations. If they don’t, it is non conformant.
If you are working on a project and you have questions about your firestop submittals, or installations please do not hesitate to give us a call. We are happy to help when we can and if you are close enough we might even swing by to help out if our schedule is open.
The 2015 IBC code section …don’t worry, it will be painless and its SUPER useful information. Stick with me please!
Section 713 is on shaft enclosures and there are a few things you really need to know. I’m going to generalize and just tell you to go online for the specifics when you really need them (or hire me and I can give them to you).
Generally a shaft has 4 sides, a top and a bottom. Your shaft may have 3 sides or it may have 10 sides, but for simplicity we will assume it is like most shafts and has 4 sides. It MUST have a top and a bottom because remember your floors are required to have a 2 hour rating (in most concrete buildings) and the shaft has to match the floor’s rating so that you can have an unprotected hole in the floor that could potentially run the height of the building.
It has to have a bottom, which could be the ground floor, or it could be a horizontal rated assembly made of concrete, gypsum or in some cases firestop materials.
It also has to have a top. That can be the roof or again it could be one of the rated assemblies we talked about. If you have a penetration through the top or bottom of the shaft you will have to firestop those penetrations.
Guess what! If you use a horizontal gypsum assembly then there are no UL listed details for penetrations through a horizontal shaft wall assembly. You automatically have to get an EJ. Is that included in your firestop submittals? It should be!
Now the top or bottom of your shaft could be part of a room, for example if you have a trash chute or linen chute then the bottom of the shaft can be the laundry or trash room provided the surrounding walls are rated and you have no prohibited penetrations.
More on prohibited penetrations in our next post! If you have shafts on your project or are concerned that your firestop submittals might be missing something, as always contact us here.