Let’s talk about Prohibited Penetrations (part 5)

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.

Are your Firestop Submittals Missing Shaft Details? (part 4)

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.

NJ DCA CEU Classes

If you want to learn more about protecting commercial kitchen exhaust or the new requirements for AHJ’s with the need for firestop special inspection or when they are required we have some classes for you to consider.  If you want information on other classes provided by DCA please see this brochure.  Sharron is excited to be teaching these two classes again this year.  I know  we will be talking about codes and standards but we actually manage to have a bit of fun.

Are your firestop submittals missing something for shafts? (part 2)

In our last blog post we talked a little about shaft walls, what they are made of and some things to keep an eye out for. We will build on that as we go.

Today we are going to look at firestop submittals as they relate to shaft wall assemblies, so the next time you are reviewing project documents you will have a better idea if something is missing. The easiest way to understand this discussion is to quickly review the UL nomenclature post found here so this will be easier to follow. If you do not know this nomenclature its much more difficult to conduct this exercise.

First let’s think about the RATED JOINTS. Let’s assume that the project has both block shafts and gypsum shafts. As you look at the firestop submittals pull out the HW (head of wall) details and look for the types of shaft walls you have on your project. For this discussion we will assume you have both gypsum and block shaft walls.

GYPSUM WALL:

You will likely have a handful of HW details but if you have gypsum shafts you need to be sure the project has a detail for firestopping this gypsum shaft. When you look at the WL details for gypsum walls, you will notice it is not like the standard gypsum wall details, namely because the shaft walls are built differently so they need to be firestopped differently as well. This will require sealant at the shaft liner as well as on the outer layers of drywall. If you allow this wall type to be firestopped when the wall construction is complete, you will not have a compliant system because you will only have protection from one side of the wall. This would create a major liability for the installer as well as the GC, building owner and building occupants.  If you are looking at a WL2000 series detail for plastic pipes, be sure to take a closer look, but do the same for all your penetration types.

BLOCK WALL

If you have access to both sides of the wall, as you would in an elevator shaft, then it is easy to firestop the head of wall joint on a block wall from either side of the wall. Likewise you can firestop your through penetrations with either a CAJ or WJ detail. If you only have access to one side of the wall, you will need what is commonly referred to as a sandwiched detail and my guess is that it will likely be a WJ detail or possibly an engineering judgement. This would allow for firestop to be installed in four steps. Typically there would be installation of mineral wool recessed maybe 4-1/2” into the joint, then firestop sealant (let’s say it calls for ½” of sealant) then another layer of 3-1/2” of mineral wool followed by another ½” of sealant. There are 4 steps to this installation, which means 4 steps to any firestop inspection as well, unless the inspector wants to try to cut into this kind of joint application, which is going to be a challenge in and of itself. This also means that the firestop detail needs to show installation from one side if this is what the installers are doing.

That is what you expect to see when you are in the field, but when looking at the firestop submittals you need to be sure that the block wall detail that is provided can actually be installed on the project. Is it physically possible? You need to be sure there is a head of wall, bottom of wall and possibly a wall to wall detail for the gypsum assembly. It is not uncommon for a contractor to miss these details, so be on the lookout for them.

Next, think about what penetrations will be going through your shaft walls. The block and concrete walls often will not have access from the inside of the shaft so a sandwiched application needs to be used in many cases, though there are devices that can be used and installed from one side. If we are working on a project with you then we can help you determine which different manufacturers products would be best for various scenarios. Let’s say your stairwell walls are block or concrete. This means the firestop details you will need will start with either a CAJ or a WJ (potentially WK for thicker walls). You will need a 1000 series detail for your sprinkler pipes and conduits, unless you have plastic sprinkler pipes then you will need a 2000 series detail as well as a 3000 series for your MC cables. You won’t need a 7000 series detail for your ducts because they are going through a 2 hour wall and will require dampers. Pull out these details and be sure that if you only have one side access that the details will allow one sided access for the installation requirements. If not, you will need an Engineering Judgment. If you are in NJ, remember DCA does not allow EJ’s- sorry NJ.

Typically firestop installers will submit details for the various penetrations through a standard wall. These may be okay if the shaft wall type is included in what is allowed in the listed detail. If it is included, then you are fine, and if not then they need to submit a new detail. This will be found in item 1 of all details. These details will start with WL for gypsum framed walls and if it is a mechanical shaft you will likely have WL 1000 for metal pipes, WL 5000 for insulated pipes, maybe WL 2000 for plastic pipes. When doing the installation or inspection of these walls you will want to be sure to check annular space and sealant depth to be sure it conforms with the details. You will also want to be sure the installer firestops the shaft liner side before the outer two layers of drywall go up as you will see in one of the later posts.

We have given you a few things to be cautious about, but in our next post we will dig deeper into this and the building code. If you have questions about a recent firestop submittal please contact us for help.

Perimeter Firestop Challenge- part 1

There are a number of discussions related to the exterior facades and fire protection. The building codes have, for some time, required that the gap, between the concrete floor and the exterior facade of a building, be filled with something that can prevent the movement of smoke and fire to the upper floors. There is even a test standard developed specific to the unique dynamics of this particular application.

This is the first of a two part challenge to the industry to make something better then what currently exists. If you have any questions about an installation on a project you are on, contact me and I will help you figure out if there are any concerns.

Firestop Classes

Hi everyone!

We have the schedule for the next semester of classes at Rutgers.

The first class – Understanding the Requirements of Firestop Special Inspection will be in Vineland on Thursday, March 29th and at Budd Lake Holiday Inn on Tuesday May 8th.  This class doesn’t go over what you need to do the actual firestop special inspection.  We discuss how the adoption of the 2015 building code changes the responsibility of the jurisdictional inspector who is now responsible for identifying who is qualified to conduct this scope of work.

The second class is on the Installation and Inspection of Grease Duct Wrap. The first date this class will be available will be in Mahwah on Friday April 6th and the second class will be in Monroe on Thursday April 26th.  In this class we talk about the test standard for grease duct wrap. We do some quick training on how to install the material, then we let half of the class participants install an actual mock up duct, while the other half of the class conducts the inspection. We discuss the various things to review during an inspection, and common errors.  The class wraps up with a discussion about some of the more complicated grease duct wrap installations.

If you are interested in joining the class, please check this site for more details and registration.

Why Firestop in Shaft Walls is Often Improperly Installed (part 1)

If you have been following this blog you know how I love to do a series of posts on a topic. If you have been to one of my classes, you know how often I segue to other topics. This one is going to be a combination of these habits and we will come full circle, eventually (there is A LOT to share with you all).

This is going to be a series dedicated just to shaft walls. Our hope is that after this series you will have a few new tricks up your sleeve  when it comes to reviewing firestop submittals in the early stages of a project and knowing better what to look for when you are walking a project during construction. This series is for firestop installers, inspectors, superintendents of any trade, building owners, architects or GC…anyone who ever has to look at that red stuff and wonder if it’s right or not.

Let’s start with looking at the different types of shafts and what purpose they serve from a code perspective.

WHY DO WE HAVE SHAFTS?
The building code basically says you have to firestop any hole in the floor, or you have to stick the hole in a shaft. There are some holes in the floor that you really need, such as the hole that is created for an elevator or stairs. There are other holes that you could firestop, but it’s easier to just protect the hole with a shaft, one such example could be a mechanical shaft.

Generally, when you build a shaft, it will have the same rating as the floors that it runs through, so in most concrete projects we are talking about a 2-hour shaft.

The 2015 IBC section 713 is all about shaft enclosures if you want some light reading. You can find copies on line these days.

WHAT ARE SHAFTS MADE OF?
Here are three basic types of shaft wall assemblies you will see: concrete, block and gypsum. We will discuss all three here and remind you of some common problems with each type. Bear in mind one shaft could potentially be made of all three materials.

Concrete shaft walls are the easiest ones to get right. One reason is because there are fewer rated joints that need to be firestopped. Also, it’s not easy to punch a hole in a solid concrete wall, so penetrations are typically planned for or avoided. Still, you may have penetrations for electrical, sprinkler or ductwork. Please remember that firestop on walls needs to be on BOTH sides of the wall. Let’s think about this for a moment and talk about the problem this creates for installers. If you only have access to one side of the wall, how do you propose protecting both sides of the wall? Hang on, we will get to that in a bit.

Block walls are not so bad to firestop either. That is except when you are talking about a stairwell, because then, the head of wall joint that requires firestop is often blocked by the stair runners. When the joint is not firestopped properly, this can leave the area vulnerable for the passage of fire, smoke and toxic gas. Keep in mind that the stairs are typically your means of egress in an emergency because you won’t be able to use the elevators. This means that getting the fire protection right in these areas is critical to the life safety of a building.

Gypsum shaft walls create the most problems we’ve seen, from a shaft perspective at least. It starts with the basic construction. Does the contractor know that they need to stagger the corners of the wall and not run both layers in the same plane? A typical 2 hour gypsum shaft wall is going to be made with 1” shaft liner and 2 layers of type X drywall. The seams of these two layers of type X should not line up anywhere, including at the corners. Since drywall shrinks during a fire, any seams that line up create an extra risk. The required overlaps allow for the shrinkage without the risk. Corners are critical because too often the drywaller lines up the two layers rather than staggering them making a straight line seam rather than a stair stepped seam.

Remember, regardless of what type of shaft you build, the head of wall joint needs to be firestopped. Remember also that it needs to be firestopped on BOTH sides of the wall. If you have an elevator shaft, then someone will likely have to ride on the top of the car to firestop the joints and penetrations inside the shaft. The same is true for a mechanical shaft except access will be… shall we say… limited, if not impossible.

Next up, let’s look at the penetrations through these shaft walls. They, too, need to be firestopped from both sides. If access is impossible there are a handful of alternate solutions. Many of these will require an Engineering Judgment that should be created following the IFC guidelines found here.

In our next post we will go over what to look for when you are reviewing the firestop submittals specific to shaft walls.

Fireproof, FIRESTOP, Fire Block- what is the difference- (part 3 of 4)

Hello again, welcome to part 3 of the series where we explain the difference between fireproof, firestop and fire block. You can get the new post here. If you missed the previous blogs here are part 1 and part 2!

Enjoy and keep learning and share this with the next person who gets here terms confused!