Episode #23 - Kit vs. Pre-Hung: Choosing the Right Acoustic Door

Kit door or factory pre-hung? It’s a question that surfaces on nearly every project where sound control matters. In this episode of Catalyst Conversations, Grace Jacob of IAC Acoustics and Mike Sirna of Hensel Diversified Construction discuss the differences between the two.

Whether you’re an architect writing specs or a contractor installing in the field, this episode offers practical insight into how your door selection can directly impact performance, reliability, and project outcomes.

To learn more about IAC's acoustic doors, visit: https://www.iacacoustics.com/specialty-solutions-systems/architectural-doors

 

 

Lisa Morrow, Brand Champion, Catalyst Acoustics Group

Hello and welcome to Catalyst Conversations. I'm your host, Lisa Morrow. Today, we're digging into a question that comes up on nearly every project, and in countless conversations with architects and contractors. Is it better to choose kit doors or factory pre-hung doors? In today's discussion, we'll explore how each option affects performance, consistency and installation, and why the right choice can make a measurable difference on the job site.

 

With me are Grace Jacob, IAC Acoustics Architectural Doors and Windows Sales Manager, and Mike Sirna of Hensel Diversified Construction who's experienced installing both types of doors in the field.

 

Let's dive in.

 

Grace, before we compare kits versus pre-hung doors, why don’t you tell me what sets IAC Acoustics’ architectural acoustic doors apart?

 

Grace Jacob, Architectural Doors and Windows Sales Manager, IAC Acoustics

 

Sure.  I have two lines for doors: one is Noise-Lock and the other is Super Noise-Lock. Super really just defines the size. Typically, I can do a Noise-Lock door up to 16’ by 16’.

 

We offer a wide range of veneer options to be stained in-field with those STC-51 through 64 assemblies and up to a three hour fire rating, but only 90 minutes with veneer. Super Noise-Lock on the other hand is anything that swings over 16’ by 16’, anything vertical lift and anything sliding or bi-parting and those come in STCs 51 and 55.

 

We offer supplied and factory-installed hardware to ensure proper fit, finish, and function in the field, as well as factory-installed window options. These are fully factory-assembled door sets that are pre-hung and swung before crating to ensure that they're going to align right in the field. Our not-so-secret sauce is the self-aligning magnetic seals. They ensure contact all around the door jamb to block any flanking paths.

 

Lisa Morrow

 

Awesome. Now, Mike, let's level set. Can you explain to our listeners what a kit door is?

 

Mike Sirna, Hensel Diversified Construction

 

So in my experience, a kit door is something that is, basically, what describes a kit; it comes with the frame, the frame is pre-assembled, but all of the seal beds, the hinges, the door leaf all comes ready to assemble in the field. So ,what we do is, we set the frame, we have to pin it in place. Then we apply the hinges to the leaf, apply the hinges to the frame,install the seal beds, install the seals in the seal beds, and then hang the door. And then we have to make critical adjustments to make sure that all of the seal beds, some are magnetic, some are just foam, that they have a proper alignment so that they get performance out of the door.

 

The other thing that kit doors have is they have a foam seal that's their bottom sweep.  That traditionally needs to be cut to fit in the field, which allows the possibility of misalignment or cutting incorrectly. We get one chance at it and it's a possibility that the door can underperform if that's not done correctly.

 

Lisa Morrow

 

So to be clear, Grace, doors from IAC come ready to install with all performance components integrated?

 

Grace Jacob

 

Correct. Our doors show up fully assembled so that all the installers have to do is wait for it…install the door..and drop the bottom seal so it makes complete contact with the threshold. The reason we factory install all the hardware is to control the quality and any variables.

 

Once you start putting holes into a sound control door, you start playing with fire. These holes must be properly sealed to ensure acoustic performance. Plus, sound control doors are a little extra thick. They're the thick boys of the world, and so the hardware must be modified to bridge that whole gap, and we take care of all that.

 

Lisa Morrow

 

Grace, how does a pre-hung door from IAC acoustic compare in the field?

 

Grace Jacob

 

Well, they're designed to work to meet STC and NIC performance specs. In acoustic installations, even a small gap or misalignment can compromise the performance, so that's why it's important that we pre-hang and swing our doors ahead of time.

 

Sound is like water, so it'll always find a leak, so you have to ensure there are none.

 

Lisa Morrow

 

So, since we are an acoustics podcast, Mike, can you talk to me a little bit about how pre-hung assembly matters for acoustic performance?

 

Mike Sirna

 

Well, like Grace had said, the factory pre-hangs and swings the door to make sure that seals are aligned; gaps look right. The biggest challenge we find in the field is improper rough openings. If the rough opening is plumb, true and correct, the pre-hung door will literally slide right in, square peg and a square hole, and the installation is seamless.

 

We find that in our experience, the lack of preparation of the opening, whether it's a kit door or whether it's a pre-hung, is usually the poison pill in the installation. Knowing that IAC prepares us for a door that has been factory hung allows us to basically continue without much worry about whether or not the door is going to be perfect.

 

We have a project with kit doors right now that the customer’s come back to us and said, hey, the gap on the door gets wider at the hardware and the door's not latching. So, these are factory-installed doors into buildings that we're working in, and what we have to do is we have to go back into those kit doors, disassemble them completely, basically back out the way that they're attached to the framing, the rough opening, shim it, and then put it all back together. Whereas with IAC, the frame’s usually welded in the situations that I'm talking about.

 

We put them in, we level them with lasers. Once the laser says it's perfect, 99.9 % of the time, the door closes and latches perfectly. A lot of times it could be just the lasers a little bit, you know, or you're looking at it and then, you know, it's close. But the thing about when IAC sends out the door, once their technicians in the factory sign it, it gets the QA sticker. We pretty much see that as it being 100%.

 

Lisa Morrow

 

Grace, is there anything you'd like to add about acoustic performance differences between the two types of doors?

 

Grace Jacob 

 

IAC has the ability to go above and beyond the typical expectation of STC options on the market. We have an STC-61 door option as well as an STC-64 door option, which I don't think there's many of those on the market and I'm not sure if there's any that come as a kit. That would be a pretty hefty kit.

 

Mike Sirna

 

That's correct. I can tell you this, we have a job right now with an STC-61, and just to give you an idea, an STC-51 is a two-and-a-half-inch leaf. This STC-61 is a five-inch leaf, it's twice the thickness, and weight wise, it's about 700 pounds. And that's just a standard 3070 door. And there's a lot of things to consider when you're swinging that kind of weight, especially in a 90-degree opening to the rough opening. So when we get into the big boys, what we call the big boys, there's a lot of pre-planning, there's a lot of stuff that we've pushed back on the factory. It has to be perfect because to try and set in a line, a 700-pound door in the field that hasn't been pre-hung in the frame or anything, there's a lot of stuff that could go absolutely wrong. And it has in the past.

 

Lisa Morrow

 

That's a perfect segue for me. I want to jump into a discussion about oversized or specialty doors. Grace, do you want to kick us off? And Mike, maybe you can jump in with some thoughts.

 

Grace Jacob

 

Sure. Not to sound like a mother of 10, but all my doors are special. Each is made to order. But when it comes to the really big ones or the sliders and anything that's Super Noise-Lock, they definitely have a longer lead time, and I want people to be able to note that. So don't wait too long to get that quoted or ordered. A lot goes into making those things as you can imagine, so we require a lot of information upfront in order to properly design the best solution for the application. When it comes to, you know, more basic oversized doors within our Noise-Lock line, think doors over eight foot, but under 16 feet, the fire rating is going to be what you want to consider because for those you can't actually get a UL label for doors over a certain size because they simply can't be tested due to their size. Instead, we can provide a UL certificate, so you can still rest assured that these are constructed with life safety guidelines in mind, but you won't be able to get an actual label.

 

Lisa Morrow

 

Mike, anything to add about specialty doors or just any closing thoughts from the field?

 

Mike Sirna

 

So, in my most recent experience, when you deal with oversized doors, they are usually quite heavy, not able to be handled manually by hand or set by hand. The critical component, like I said before with most doors, is an opening that is plumb, true and correct, meaning the threshold is level, and I mean level within an eighth of an inch. Any variation of vertical plumb, being out of plumb vertically or being out of level horizontally will absolutely affect the way the door looks. So, on oversized doors, the onus is on the contractor to make sure that he provides the install crew, which is us, an opening that is flawless. And if it's not flawless, the only thing we can guarantee is the door's not going to look right.

 

Lisa Morrow

 

Thank you. Mike. Grace, do you have any last takeaways for our listeners?

 

Grace Jacob  

 

Yes, I would like to say that if performance and reliability matter, especially for sound isolation, IAC's engineered factory pre-hung acoustic doors deliver consistency and performance that field-built kit doors just can't match. If your door is going to be tested after installation, you'll want an IAC door in that rough opening.

 

Lisa Morrow

 

That's just about time. Thank you both, and thank you to our listeners. For more on IAC acoustics architectural doors and engineered acoustic systems, visit their product pages and specification guides at iacacoustics.com. If you enjoyed this conversation, be sure to subscribe or share this episode with a colleague. Thanks for listening.