Myths of fire-rated walls and doors between house & garage.

A common mistake that home inspectors make when inspecting single family residences is related to opinions stated about the requirements for fire separation between the home and the attached garage. 

Their comments often leave them “out on a limb” when repairs are called for and a builder or repair person informs them there are no “fire-rated” requirements.

I should clarify, this article is based on 2015 IRC and may not be consistent in every regard with the codes amended or otherwise in your area.  Also earlier versions of the codes merely referred to garage house separation as opposed to more modern standards that refer to fire-separation.

The wall between the house and the garage–believe it or not–is NOT a fire-rated assembly and is referred to in the code as the “Dwelling-Garage Fire Separation.”

Meeting the “fire separation” requirements is really quite simple and minimal compared to what would be necessary in an actual “fire-rated assembly”  (As would be required between multiple dwelling units like condos, townhouses and duplexes etc.)

Typically, ½” drywall (or equivalent) is all that is necessary to meet the separation requirement. 

If there is living space above the garage, the ceiling would have to be 5/8” type “X” drywall (or equivalent).  Again, this is not a “fire-rated assembly,” but merely what is required to meet the proper “fire separation” requirements.

These wall and surface finishes have to have a flame-spread index not greater than 200, however wood frames and trim around doors and windows are excluded from this requirement.

Duct-work inside the garage, or duct-work that runs through these fire-resistant surfaces must be constructed of  minimum No. 26 gauge sheet steel or other approved material and shall not have openings into the garage. So this means no return air registers or heat supply registers inside the garage.

Openings around other types of penetrations in the walls and ceilings (ductwork, pipes, wires, etc) must be filled with an approved material to resist the free passage of flame and products of combustion.  There is nothing in the code, for single family residential construction, that prohibits plastic piping through these fire-resistant surfaces.  This is another common incorrect call-out by home inspectors.  The openings around them merely have to be properly sealed.

Pull-down stairs in a garage ceiling would be required to meet the requirements of 1/2 drywall or equivalent, or have a 20 minute fire-rating.

The door or doors placed in this “fire separation” are also frequently misunderstood and incorrectly reported on.

For the door between the house and the garage, all that is necessary is to install a door that meets the “fire separation requirements” of the code.  Of course this door can never lead to a bedroom.

There is nothing that says it has to be a “fire-rated door,” as frequently reported by home inspectors. 

While this may seem confusing, if one looks at the code it becomes clearer.  It also reveals the source of some of the confusion.

To meet fire separation requirements, the door must be one of three types of doors:  a solid wood door not less than 1-3/8 inches thick, a solid or honeycomb core steel doors not less than 1-3/8 inches thick, or a 20-minute fire-rated door, with a self-closing device.  Another thing to note, is that a 1-3/4″ thick solid wood raised panel door would likely not comply because the minimum thickness at the recesses would likely be less than 1-3/8.”

As a side note, that little comma after “door” in: “door, with a self-closing device,” is consistent with its pertaining to all three choices–not just the 20-minute type door.  If it applied to only that type of door the comma should not be there.

The first two types are fairly self explanatory but the inclusion of the third type has lead to a great deal of confusion because a door that is a “20-minute fire-rated door” leads one to think that the door in general, and thus the walls and ceiling, have to somehow be “fire-rated.”

Also having a “fire-rating” (as all materials in the home do) does not make any of this a “fire-rated assembly.”  It just means the fire-resistant surfaces are specified to be constructed of materials known to have known fire-resistant characteristics.

For a door to achieve a 20-minute fire-rating it has to go through testing procedures by Underwriters Laboratories and then it receives its “UL listing” as a fire-rated assembly. 

All three types of doors will require weather-stripping/seals on all four edges of the door to prevent the passage of gases that may be drawn into the home, as well as meet energy efficiency standards and fuel gas code standards.

Hopefully this post will help clear up some of the confusion.

By Charles Buell, Real Estate Inspections in Seattle

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  1. Joe Lundequam says

    Thank you so much for all your posts. The industry is better for what you bring to it.
    Just to be clear and to settle an argument with another Inspector; the door between the garage and house is required to be self-closing, yes?

  2. Daniela says

    Re doors between house and garage: I would like to put a cat door in the door from the kitchen to the garage, but I suspect this would not be up to code — maybe not so much because of fire, but because of the danger of carbon monoxide. My garage (in Oregon) has stuff in it; the car is never in there, so there is no carbon monoxide danger to me. And I have a carbon monoxide detector. What do you think about a car door through the door between garage and kitchen? If I ever sold the house, would I have to get a new door to replace the one with a hole cut in it?

    • Charles Buell says

      If you put a hole in the door you would end up having to replace the door when you sell the home, and you might have issues with insurance if the door is compromised. The door is damaged both for fire-resistance and fume intrusion. I cannot recommend doing it.

      • Well, I pretty much thought so. Thanks for your advice. I guess I can’t get away with it.

      • Hi Charles.

        I have a further question on this subject. I would like to install a door to my garage (mainly so that I could move my cat’s food etc into the garage area). What would be your recommendation for the cat door. Would it be best to put it in the door or in the wall?


      • You have to read IRC 302.5.1 here is very clear about opening between garage and residence

    • Kayli Ana Portanova says

      I just bought a home with one and it passed inspection and we were able to buy it … and now I have to go through replacing the whole door which is annoying as hell. IMO keep your cold air inside and fumes out by leaving the door to garages whole. – from the person who bought a house after someone cut a hole in the door.

  3. Bandacoo says

    Hi Charles,

    Good article.  What about glass in the door between the garage and living space?

    ⁣Thanks, John​

    • Charles Buell says

      It would have to be fire-rated glass—not likely going to happen, but could theoretically.

      • Is there anything you could cover the glasss with to make it meet the fire code?

        • Charles Buell says

          Not that I am aware of

          • Incredible information, Charles. Thank you so much for sharing your knowledge. I have spent the larger majority of this morning shopping for a fire-rated house-to-garage door/fire door/interior garage door. You’re in luck, Judy! I stumbled upon an option to answer your inquiry this morning: There are 20-minute fire-rated glass doors through TruStile.

            I have no idea how much these doors cost, but dang, they look nice so it’s probably worth investigating.

  4. If I use a solid wood door or a solid or honeycomb steel door with auto closing (gravity) on a rolling frame and ensure it is sealed on all four sides, I would have a 1940s type fire door that I could use between my garage and entryway/mudroom. Correct?

    • Charles Buell says

      While the idea seems logical, I would run it by your local jurisdiction, for a better answer than I can give you.

  5. Good evening Charles. Thank you for all the knowledge that you share. My question is when noting that there is a glass door between the garage and the house how do you state it in your report? In looking for the answer to glass in metal fire rated doors, I realize that I did not look at the door for UL listing.

    • Charles Buell says

      It would have to be a fire-rated door, and the glass and frame for the glass would have to be fire-rated as well. Fire-rated glass is obvious as it is only going to be single pane and has an etching that states its fire-rating. These are going to be very unlikely in a residential installation and I would start by “assuming” it is not correct until proven otherwise.

  6. Mark Baliles says

    Hi Charles.
    What would be the issues involved in creating a closet in an attached garage attic, accessible by a door from a 2nd floor bedroom?

    • Charles Buell says

      Interesting question. Since the closet is not likely considered “living space” it might be easy. If it is considered part of living space you would likely have to add more drywall to the ceiling of the garage. You should ask your local jurisdiction—as they will have final say.

  7. Glad to find this interpretation of the Seattle Residential Code for dwelling-garage separation with regard to fire rating. I was surprised that the code appears to only require 5/8 type X on the ceiling of a garage when a bedroom (or other living space) is above. My experience from my drywall days in Page, Arizona (about 25 years ago) tells me that 5/8 type X is also required on all walls of a garage that are adjacent to any living space. The Seattle Residential Code doesn’t even appear to require the 1/2 inch, 45 minute rated drywall on these adjacent walls, which is backed by the fact that none is stocked at any Puget Sound Home Depot.

    • Charles Buell says

      This all IRC, International Residential Code, not Seattle specific. 1/2″ drywall is all that is required on the wall between the house and the garage and on walls that support rooms above the garage. I do not know if Arizona has made the code more restrictive or not, and 25 years ago would have defaulted to UBC (predates IRC) which indeed may have been more restrictive.

  8. Herbert Birthelmer, PE says

    Excellent description of the often misunderstood requirements. One question, though: Where does the code require a seals or weather-stripping at the garage door? While that requirement apply to doors to water heater compartments inside living spaces due to the combustion air draw (see IPC), I didn’t find a reference to doors to residential garages. Can you clarify?

    • Charles Buell says

      The weather-stripping of the door is going to come under fuel gas code and energy code.

      • Herbert Birthelmer, PE says

        I think the door sealing demand is a misinterpretation of the code. NFPA 54 (Fuel Gas Code) is dealing with gas piping, which is not relevant here. While the energy code actually refers to “sealing between garage and conditioned spaces”, this aims at sealing between door jambs and framing, same as for any all exterior doors and windows, to reduce energy loss. No weatherstripping is required for entry doors. The point is, while it might be a good idea to seal the door leading into the garage to conserve energy, it has nothing to do with the code intent to slow done the spread of a potential fire in the garage, which is the only safety issue the code is addressing.

  9. Thank you for the helpful article. I’m building a custom house, the garage is tight and I’d like to use a sliding door into the house to save space. The GC says no, but in reading IRC 302.5.1 I don’t see why I can’t use a solid wood sliding barn style door with weather stripping. It would be a custom installation, but certainly feasible.

  10. Thank you for that great article…i installed a solid core 1 3/8 6 panel door in between a garage and the kitchen..the inspector said this door needs to have a metal tag, is this a legitimate request?

    • Charles Buell says

      The reason the inspector wants to see the tag is because then they know it is a 20 minute fire-rated door and meets one of the choices for type of door for garage/house fire separation. It is not likely that any raised panel, 1-3/8″ door will ever have such a rating or qualify for proper garage/house fire separation.

  11. Frank Smith says

    I am a little confused. Is a raised panel steel honeycomb door with seal and self closing device adequate?

    • Charles Buell says

      It certainly can be. Most of those doors will have a 20 minute fire-rating sticker somewhere on the assembly. Without that, I cannot tell you for sure.

  12. Paul Rogers says

    What about the garage wall this is not common to the house (the exterior wall)? Does it have to have drywall or can the framing be left exposed?

  13. Brett Vanderford says

    Does the door have to open inward into the house or outward to the garage, or does it matter?

  14. What are the codes for a closet under the stairs to the second floor with the entrance to the closet in the garage. (One or two 5/8 rock on walls and ceiling .Is a door needed? Thanks

    • Charles Buell says

      I do not have enough information to answer your question. Fire separation requirements are likely going to be the same as if the entrance was to the house. Door has to meet fire separation requirements as do the walls and ceilings.

  15. Great information. I have 5/8″ sheetrock on the inside of my attached garage (living space above garage). I’m now finishing my basement (same level as garage). Do I need 5/8″ sheetrock on both sides of the garage walls or is this only necessary for the inside of the garage? I will walk through my garage in to the finished basement. Hope this is clear.

    • Charles Buell says

      You should always get these kinds of questions verified with your jurisdiction, but generally 1/2 drywall is all the fire separation necessary from the basement. That said, it likely should already be there at least on the garage side as it is a living space supporting wall it sounds like.

      • The reason I am asking is I removed 5/8 drywall from the basement side and plan to install 1/2″ when I drywall the entire basement. I believe they used 5/8″ inside the basement previously because this is what the contractor happened to have at the time and what they were using inside the garage. I will check with the town to be sure. I really appreciate the response.

  16. Newell Harward says

    I have a carport attached to my home built in about 1983. There is a window in the family room next to the car port. I want to enclose it and make into a garage with windows on the outside wall of the garage and keep the window for light and sight from the home through the garage. If I change the window to a fire rated with no vent, would it meet code? I also plan to use a garage door with all glass.

    • Charles Buell says

      I cannot answer your question as it applies to your jurisdiction. I suspect both the door and the window could be done if they are both properly fire-rated. This question should be asked of your jurisdiction in the context of the permit application.

  17. Hi Charles, great information. Would a home built in the 1960’s typically be required to adhere to these fire barrier standards? Or would it be grandfathered? When did fire barriers between garages and living spaces become a thing?

    • Charles Buell says

      Certainly the requirements in 1960 were not the same as current requirements but fires do not understand grandfathering so any improvements that can be made are warranted in my opinion. Modern fire-separation requirements likely take to the 80’s—not sure of exact dates but were certainly in place at the time of the first IRC codes in 2000.

      • I’m pretty sure fire separation was required in 1960.

        My house was built in 1961 to pretty minimal standards with a layer of 5/8″ or double 1/2″ drywall running all the way to the roof between the garage and adjacent living space. (Some holes were subsequently poked through this separation by prior residents, but I’ve patched all but one of them.) I am confident that it wouldn’t have been built that way unless some sort of fire separation or fire barrier was required at that time. Oh, it was also built with a self-closing fire-rated weather-stripped door.

        I fixed the self-closing device because it didn’t usually latch, but pulled out some of the weather-stripping that I thought was interfering with the door fully closing in the process. I need to put replacing that on my to-do list.

        • Charles Buell says

          When you start to dig into the past regarding these requirements it can get difficult really fast. You might find this link interesting:

          • Thanks, Charles. The link is interesting. Whatever code was being enforced here in Contrast Costa County California back in 1960-61, it seems that the building department understood it to require fire separation. I have no beef with the people who built my house back then, unlike the subsequent remodelers/saboteurs, but I see no sign that they voluntarily exceeded what was required by the AHJ, so I assume that they put the double 1/2″ drywall up and installed the fire-rated door because they had to.

  18. Is there any covering that can be applied to the garage side of an 1 3/8 panel door to make it fire compliant? Drywall, plywood or whatever?

    Idea being to preserve the decorative appearance of the rest of interior doors in the house.

  19. If there is a garage apartment (living space above the garage), I know that the ceiling has be 5/8″ gypsum and no penetrations. But I didn’t think the walls had to be drywall so I installed 1/2″ cabinet-grade plywood. We were signed off for electrical and gas but now the inspector is saying that I have to cover all walls with drywall (e.g. go over the plywood or take it out). Is this right? Is it because walls are supporting structure? If I added another layer of wood, would that work?

    • Charles Buell says

      Yes, any supporting walls of the second story living space must be drywalled per code. You might get approval to install plywood over the drywall but I doubt two layers of plywood will pass. Consult with the jurisdiction.

      • Thanks – I REALLY appreciate your input and response. Really disappointed that my GC missed this one. This is gonna cost $1000s in time and materials…what a nightmare. Cant believe it didn’t get mentioned when we were discussing the stairway – think some of the inspectors are unclear on this…which verifies the importance of this article.

  20. I am planning to build a carriage barn with living space in the loft and 1 or 2 of the lean to’s on the side or back of the barn. The main part on the barn I plan to use as my garage/ work shop which I will store my cars/ trucks in. I plan on going with a barn manufacturer who specializes in these types projects, but I know my county inspectors are real sticklers. I want to keep the “rustic” wood look through out the building and avoid using sheetrock as much as possible. So if my garage is below the loft where my main bedroom will be, how can I get it to pass code without sheetrock on the garage ceiling, besides an expensive sprinkler system? Any advice would be greatly appreciated!!

    • Charles Buell says

      You have gone past my paygrade on this one 🙂 I recommend you run this by your building department for the answer—I suspect it is going to be difficult though.

      • Only way to do it that I know of is to apply drywall first per code in all applicable areas (5/8″ & tape all joints). Then apply wood over that. Also recommend that unless you are using a channel rustic profile or something like that that you paint the wall black it you don’t want to see white through the joints when the wood shrinks. Been there done that. 🙂

  21. Do you know if the man door entering into a garage can go through a mud room in the garage first or do I need to put in 2 doors. One directly into the garage and another into the mudroom? Thanks

  22. Mark Jones says

    Thanks for this information. If I have breached the ceiling in my attached garage by creating a simple opening between joists, trimmed it out and just set a painted piece of plywood over the opening; how can most easily remedy this for inspection before sale purposes? Can I simply cut a piece of drywall and lay it in place of the plywood?

    Thank you for your time in advance.

  23. Can you comment on an attached garage that was recently attached to a stucco wall that was the original exterior wall of the home. Does the stucco require a new layer of drywall? What about the cement foundation that is part of the wall below the stucco?

  24. I am bulding a 2nd story living area (game room) above my unfinished garage- We are creating a hallway that leads to our exterior w/ a fire rated door. The question we have is that in keeping with the style of the interior, we were planning on insulating the walls, and rather than drywall, using shiplap on the walls- Does that meet the same code standard as drywall? Also, if we do a 3 inch layer of spray foam insullation on the garage ceiling, does that suffice, or would we need to finish the ceiling of the garage with either drywall or shiplap?

    • Charles Buell says

      I do not know what you mean about “creating a hallway that….” All surfaces that are below and/or supporting the upper structure is required to have fire-resistant materials installed, typically 5/8″ type x drywall on the ceiling and 1/2″ drywall on the walls. No exposed foam is allowed exposed on the interior of the garage. Any doors between living space and garage are required to meet fire-resistant requirements.

  25. James Gainfort says

    Did the Code ever require garage floors to be LOWER than the adjacent floor of the residence as a measure against migrating carbon monoxide/other gases from entering the house?

  26. We have a garage that was converted into a living room and laundry room. Obviously, it cannot be used for an automobile anymore. Do the same rules still apply for cutting through or making a whole in the firewall?

    • Charles Buell says

      What do you mean by “firewall?” Is there a garage or is it attached to another building like a condo/townhouse? I assume the overhead door has been removed and walled in?

      • I’m sorry. Let me be specific. I meant the fire separation wall between the home and the attached garage. The door to the garage was removed and the space enlarged to open up the garage to the home and the garage is now a living room area and a part of the home. Specifically I was wondering about the attic area above the living room (which used to be the garage). The fire separation wall has another whole cut in the attic for the AC duct to go through to the living room. I am wondering if the old rules apply now that the garage is a part of the home and can no longer hold a car.

  27. I am planning to replace a wood hollow core door between my garage and single family residential laundry room (LR has access/egress to the rest of the home) with a fire rated door. Should the door swing into the laundry room or into the garage?

  28. Henry Guttormson says

    Hi Charles:
    I am remodeling/refurbishing my attached garage and am confused as to what the 2015 IRC reqts are concerning interior wall sheathing. My garage is attached to my single story, hip roofed house by one wall. The garage is currently completely drywalled with 5/8 drywall over the 16″ spaced wall studs and ceiling joists. I want to remove ALL the drywall and simply insulate the walls and then put pegboard over the studs which I believe is OK for exterior walls as I have seen in this thread. But what about the wall shared with the house?…it is insulated and drywalled on the house side of the studs so can I just put pegboard on the garage side?…or do I have to sheath it as well with drywall?…If I have to sheath it, do I have to use drywall?….can I use a plywood or OSB product instead? For building codes, my city uses 2015 IRC without amendments and without any other requirements.

    • Charles Buell says

      A assume the non-house walls to not support upper levels. If they do not then I suspect the pegboard may not meet the requirement for the insulation to be covered. Cover with drywall or plywood first would be my recommendation, but I recommend consulting your local building department.

      • Henry Guttormson says

        Hi Charles:
        Thanks for the info. Since my house is single story, non-house walls only support the roof structure which is a 5:12 hipped roof. They have a 5/8″ exterior drywall mounted between the studs and the brick facia or veneer on the outside. The builder also put in those 1 x 5 diagonal braces on the studs. The insulation I plan on using between the studs is the R-13 roll insulation which is about 5″ thick and then the paper facing would be on the interior side. I dont think I need the sheathing for structural support so that is why I would like to go with just pegboard on top of the paper faced insulation…but if there is a question I will contact my city. I really would like to use plywood or OSB if I can because I hate drywall in the garage as my garage is a working place and the drywall is fragile and messy even under pegboard. For sure I will sheath the wall that is shared with the house before I pegboard it. Can you tell me what paragraph or section in the 2015 IRC actually discusses this subject matter so I can study it some more?

  29. Hello Charles,
    We are a small community and bought a residential building in CA to convert it into a commercial building(church).
    I have a question regarding these 45 minutes fire doors for commercials. There is this door between the garage and the building hallway. The wall between the garage and the building is one hour rated wall. Is that true that all commercial single fire doors needs to to be self-latching and self -closing? Also what kind of doorknobs has to have? We have already bought one metal door but is not self closing and had the 2 door knobs like a regular door. What is your advice on it?

    • Charles Buell says

      Hi Alice, unfortunately I am not going to be able to be of much help to you on a commercial building. You would be better served asking the local jurisdiction as to the requirements.

  30. John Powell says

    You wrote about and posted information about fire rating myths for doors between house and garage which I found most interesting. I have a related question. There is such two doors between garage and interior of house of a kitchen and laundry room. One of two doors is hopefully a barn door type, sliding on a heavy duty track overhead. There should be no problem with the door’s construction and frame at opening isn’t required to be fire rated materials. What I understand is that at place where door is covering the “cased opening” then there must be seals preventing carbon monoxide from passing through edges. As most barn doors swing freely at bottom there would be a need to prevent it from doing so as to enter a special kind of threshold track. Am I right about this scenario?

    • Charles Buell says

      John, I am not quite sure about what you are describing, but the opening that is in the actual wall that separates the garage from the interior space (guessing laundry room?) has to meet fire-resistance requirements—so that is where the door that meets those requirements would be located.

  31. In my situation, the door from the garage to the dwelling is at the top of a set of 8 steps in a finished drywall stairwell. Does that door need to be of said fire rating? It is a hollow core unit now and id like to replace it.

  32. If you mean the landing the yes that is garage floor level at the first step then you continue to the door that is then when opened in an interior hallwayz

  33. Wow sorry for the spelling errors!!!

    • Charles Buell says

      The stairwell would be considered part of the garage if the door is not at the garage floor level and as such would need to meet all the fire-resistance requirements. The stairs themselves would likely prove to be problematic if the fire-resistant door is not at the garage floor level prior to entering the stairwell.

      • Thank you for the explaination. Yes the door is at the top of the steps and the lower landing and stairs are open. Foundation block is about half way up and then drywall finished walls complete the stairwell up to the hollow core door as it is now.
        So a fire resistant door would be appropriate.

  34. Maelene Mays-Rodriguez says

    And if there is a breezeway separating the house and garage. What types of doors are required from garage to breezeway?

    • Charles Buell says

      Typically doors to breezeways have not fire-stopping requirements but the connecting roof structure likely does. Can vary from jurisdiction to jurisdiction as well.

  35. I am considering buying a older single family home that later had a 2 car garage added onto the home. Two rooms in the house have windows that face into the garage. The rooms both have other exterior windows. Would removing the original windows and adding commercial grade 45-60 minute fire rated glass block windows be sufficient? Or do I need to remove the windows completely?

  36. Tony Crawford says

    Hello, A house I am looking has a cat door in the garage door from the house. Will that be a problem with a VA appraiser?

  37. Question. If the wall separating my house from the garage has 1/2 plywood on the garage side, spray foam insulation and 1/2 drywall on the interior. Do I need to drywall over the plywood inside the garage to meet fire regulations?

    • Charles Buell says

      I would think so, but this is a question you should ask your local building department as some may be OK with it.

  38. Barbara M LaChance says

    I am selling my home and the buyer wants the door and frame between the dwelling and garage fire rated to 20 mins, and similar for the garage attic access (currently a 2’ x 2’ piece of plywood resting on trim). What must I do to meet the request? Is there ‘fire rated’ framing for doors? Likewise, your recommendations for the garage attic access? Thank you – this is a great site with helpful information!

    • Charles Buell says

      There is no requirement for the door or jamb to be 20 minute fire-rated. Likely the access hatch should be drywall instead of plywood. Consult with your applicable building department though.

  39. Just to be clear 1- 3/4 inches (44 mm) is thicker than 1-3/8 inches (34 mm)

  40. Jake Howard says

    Im selling a house in Olympia and the buyer is requesting the garage to have a lid, right now its open to the rafters but the walls touching the living areas are insulated and rocked,

    Thanks for a great blog by the way,

    • Charles Buell says

      From what you describe it sounds like you may be good to go. The only time the lid needs to be covered is when the garage supports living space above and then the walls would need to be covered too. Do you have pictures of the wall between the house and garage?

  41. Leonard B powell says

    Hi I have a garage under my house, it has 5/8 type x on the ceiling but just plain masonry on the 3 walls , including the wall connected to the home, should it be covered also with 1/2 sheet rock or is concrete block ok for fire separation.

    • Charles Buell says

      I cannot imagine the concrete block not being adequate—I guess if there is any exposed wood between the blocks and the drywall might be required to be covered but you would have to check your jurisdictional requirements for that.

  42. Regarding the myth on fire rated walls and doors between the house and garage. Does the drywall have to be mudded and taped at the seams?

  43. I just went for my C of O and the inspector is questioning if i should have a fire rated door at the bottom of the stairs from the garage to the basement. There is a door currently installed but is not fire rated. I cannot find anything in the code regarding this. Any ideas?

    • Charles Buell says

      Per current IRC it does not have to be “fire-rated” although that is one option. Solid wood minimum 1-3/8″ thick and self closing and weatherstripped also meets the requirements. Regardless it does need to meet fire-resistance requirements as spelled out in the IRC.

  44. Hi charles we are selling a 1920’s bungalow with a garage under two rooms of the home. The home inspector is requesting gypsum board on the ceiling. Is this required in a home of this age? Thanks

    • Charles Buell says

      Inspectors typically do not “request” anything, but instead “recommend” improvements and upgrades for safety. I would do the same. This would not only involve the drywall for me, but insulating and doing any re-wiring that it warranted—before it is covered over. This is not something, in my opinion is the responsibility of a seller, but could be undertaken by either party. If it is actually going to knot up the sale, then that could be a problem. Most people are going to want this fire-resistance requirement upgraded to modern standards. Typically I see this kind of improvement not get done by the seller but instead the parties work out an agreeable credit.

  45. Robert Hollifield says

    Hi Charles, I happened upon your blog and am hoping you could give me some info. I’m in southern California but I’m hoping the building codes would be similar. I have a single car garage with a 400 sq. Ft. workshop. Currently there is a walk through door way with no door. Also there is a 2 sided gas wall heater on the seperating wall. I have a couple questions as to what I would need to do to permit this room as living space. I assume I would need to remove the heater and replace it with a single side unit and enclose the garage side with drywall. Also I understand that I must close the walkthrough off and drywall it if I were to use it for guest quarters. My question is since my garage is entirely drywalled except for the areas mentioned would I still need to go into the attic and drywall to the roof? Also would my garage require a exterior man door?

    • Charles Buell says

      These are questions better answered by your local building department. Give them a call they are almost always willing to help or tell you where to get help.

  46. Tangier Clarke says

    California resident: I need to replace an old 24″x80″ door and frame in a 1930s home which leads from inside my garage to a downstairs basement and the crawlspace under the house; the kind of basement just big enough for a water heater, old heating furnace and to store a handful of things, not an actual spacious basement.

    The old door is solid wood as it has some nice weight to it, but just has a sheet of metal nailed
    onto the front (facing the garage interior) and exposed wood like a regular door on the basement stairs side.

    Would I need to replace this with a fire-rated door. I am having a very difficult time finding any place that has a pre-hung 24″x80″ fire-rated door.. Nothing from Lowes or Home Depot offers that not even by special order.

    • Charles Buell says

      You would have to check with your jurisdiction, but as long as the door is solid wood and minimum 1-3/8″ thick it may be OK. Likely needs a self closure device. If you still want to replace the door, a fire-rated door is only one option to meet the fire-separation requirement.”the garage and residence shall be equipped with solid wood doors not less than 1-3/8 inches in thickness, solid or honeycomb-core
      steel doors not less than 13/8 inches (35 mm) thick, or 20-minute fire-rated doors, equipped with a self-closing or automatic-closing device.

    • John Powell says

      Could be that you are looking for a real narrow fire rated door. 24” is very narrow. Try a 32” – 36” wide door.

  47. Fire walls are not CO walls! CO goes right through drywall, especially along edges, corners, seams and where openings of any size are cut for electric outlets, wall switches, and ceiling fixtures. Only the IMC (in 403.3), not the IRC, requires residential attached garages to have 100 cfm of continuous ventilation per bay. This is the only sure way to keep CO and other toxic exhaust gases from being drawn into the home (or accumulating in the garage) after a cold start, before catalytic converter warms up (risk is greatest in winter when outside air is colder than garage air)

    • Charles Buell says

      403.4 is not an IMC number. CO will not move through drywall. Please provide a better reference to support what you are saying.

  48. Dave Jamison says

    I am having a bathroom constructed that is only for the garage, there is no other access to it.
    Does this require a 20-minute fire rated door?

    • Charles Buell says

      The simple answer is no. The real question is, does the door need to meet fire-separation requirements. I doubt it, because the bathroom would not be considered living space and the bathroom is not inside the house. Check with your jurisdiction, they may have another opinion.

  49. Judi Peterson says

    We are selling our home and the inspector made the following finding:
    Garage walls adjoining living space were not fire-taped as is required by generally-accepted current safety standards. The Inspector recommends that the wall be fire-taped by a qualified contractor.

    Is there something special about “fire-taped” between a house and a garage? I’m not finding anything online that suggests anything other than drywall tape and mud.

    • Charles Buell says

      I think it is going to be hard to find a specific requirement for taping and mudding of drywall between the house and the garage. It is generally accepted practice to do so, and sometimes this practice is called “fire-taping,” but again, it is merely common practice. I think this taping requirement myth comes from “fire-rated drywall assemblies” where taping and mudding IS required. Since the garage/house wall is not a fire rated assembly but a structure that must meet “fire-resistance” requirements, there is no code I am aware of that specifically requires mudding and taping. You may also have jurisdictional requirements to check.

  50. Hi, I am selling a 40-year old house and need to change the garage entry door to be fire rated. Is there any store that sells the fire rated with 1 3/8 thickness or can it be custom ordered? I bought a standard one from home depot and it’s 1.75 thickness, so we will have to change the door frame. Would like to just switch out the door if possible. Thanks!

    • Charles Buell says

      Who says you have to install a “fire-rated” door? It is not just the door that is fire-rated. That would include the jamb, weather-stripping, auto close device, threshold etc. If you are just replacing a door that had an 1-3/8″ door previously, you can put in an 1-3/8″ solid core wood door and meet code requirements. Of course adding weather-stripping and auto closure may also be necessary. In my opinion it is going to be easier to take out the whole existing jammbs and door and install a new fire-rated door with jambs and auto closure and weather-stripping.

  51. Marcin Gajowniczek says

    Hello Charles,

    Does a hollow metal door 18 gauge, double leaf (3’ and 4’ wide) 1 3/4” thick with Polyurethane core satisfy the irc definition of ’solid or honeycomb core steel doors not less than 1-3/8 inches thick’?

    Thank you

  52. John McCarthy says

    My local building inspector is telling me the door needs to be 1 hour rated and the common wall between garage and occupied space (kitchen) needs a 1 hour rating with taped 5/8″ Type X drywall with FC sealant for penetrations. Does this fall under the AHJ or is he interpreting the code incorrectly? I am in NH. See you on AR. Thank you!

    • Charles Buell says

      John, was this an AHJ or a home inspector telling you this? Unless you have some very seriously amended single family residential code, what they are telling you is not consistent with IRC.

  53. Hi Charles,
    When having a new door and door jam installed in the entry between my garage and kitchen, the installer is telling me he needs to also install a threshold. My existing door has a door sweep. My floor is tiled right up to the edge of the kitchen and I’d rather not have a threshold put on top of my tile. Can a door sweep be used to seal off the bottom, or some other type of seal instead?

  54. John McCarthy says

    Charlie, I hit the “Reply button,” but don’t seem to be able to reply. It was one of our town’s two building inspectors. I called a home inspector for a second opinion (why), and he told me home inspectors are trained to look for any rating on the door. Whether it is 20 minutes or 90 minutes is essentially irrelevant. I have a hunch if I had asked our town’s other building inspector, I would have gotten a different answer.

  55. Charles Buell says

    John, I would ask the AHJ for a code cite to support what he is telling you. Color me skeptical.

  56. John McCarthy says

    Thanks, Charlie. I agree with being skeptical. As a purely practical matter, a permit is not required to change out a door, so the only one I need to satisfy is the home inspector when I accept an offer from a Buyer and they proceed with a home inspection. The door will be NFRC rated and depending on the availabilty, 20, 60 or 90 minute rated.

  57. Courtney says

    Hi Charles– thanks for all of this great info. I have an attached sheetrocked garage that passed inspection with no problem a few years ago when purchasing the house. I am looking to frame over top of the current sheetrock, insulate it, and and panel it with plywood. Two walls are shared with the house. If the sheetrock beneath my new additions is ‘fire-acceptable’ will my new framing, insulating, and plywood sheathing be a problem? Thanks for your thoughts.

    • Charles Buell says

      Can’t visualize what you are proposing—sounds like something you would need to ask your local jurisdiction

  58. Mark Durham says

    Hi Charles!

    I have an attached “garage” (3 rooms – workshop, garage, storage room) with OSB walls and ceilings. It has a finished loft over the entire structure. I’d like to make the loft a living space, so can I just sheetrock (5/8″ type X) over the OSB or do I have to remove it and replace it with the sheetrock? And if I install sheetrock on the ceiling (one way or the other), will I need to do the same with the walls? Thanks!

  59. Lance Winter says

    Hi Charles,
    Does a 1 3/4″ wood composite door meet the 1 3/8″ solid wood door requirements for R302.5.1.1 Opening protections?
    I have just bought a 1 3/4 ” solid wood door from my local rebuilding center. I just cut the door down to 32 x 50 “. I ‘ve found out my solid door really is a particle board composite construction. I’m guessing the door does not meet the ‘solid wood door not less than 1 3/8” requirement.
    BTW great information on your site.

    • Charles Buell says

      Since many 20 minute doors are wood composite I would consider it likely but your local AHJ is really the one that is going to have the final say.

  60. Debby G. says

    I live in a rental property. The door from my attached garage into the house had large gaps between the sides of the door and the frame with molding installed. The owner had the maintenance guys come out and put more molding over the existing molding and moved the strike plate further inwards towards the house side of the door causing the door to have to be pulled harder to latch attempting to make better contact with the molding. Now there is still light showing through the sides of the door at night when I look from inside the garage towards the house. The door has to be pulled a few times as hard as I can to get it to latch and my kids can’t possibly close the door themselves it’s just too hard. Being that this is a rental property and I’m having great difficulty getting quality repairs done here what would you recommend me do to help light a fire under them to address my issues. I have several that have been ongoing since I moved in 6 months ago. It took them almost 90 days to get me hot water. Also, for attached garages is there any codes that require specific ventilation to keep the garage cool during the 100+ degree summer days?

    Thank you!

    • Charles Buell says

      All these questions are best addressed by whoever governs landlords in your area.

    • An enclosed garage is not normally a conditioned environment suited for living. As such there are no requirements for ventilation to lower air temperatures. Codes are a “threshold” rule, establishing a line not to cross. To put a car into an enclosed garage there must be a means of entry and exit for the vehicle. Conventionally there is a garage door that rides tracks at edges. As the perimeter walls which are not shared with the dwelling’s heated spaces are left without insulation then inside temperatures can really build up with direct sun radiance through roof and walls. Security becomes a factor when you need ventilation. Opening the garage door can signal a breach in security. Same with a window.

  61. I have 2 doors in my garage, one leads to the main house and the other to a spa/hot tub room. This room is not conditioned space. Does the door leading to this space need to meet fire ratings?

  62. Michael Elsman says

    Any idea if an exterior terrace over the garage counts as a “living space”?


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