Accessing Attic Via Exterior Door Gable Wall
Debra_Ann
| Posted in General Questions on
The house we are designing will have an attic with roof trusses. No ductwork in it, just lots of insulation. The only time I think it would need to be accessed would be to check for or repair roof leaks. Properly air sealing and insulating an indoor attic access hatch seems somewhat expensive.
Does anyone access their attic through an exterior door in the gable wall – where it would need to be weatherproof, but not air-tight or insulated? Not sure if that is feasible or practical.
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Replies
Debra,
Q. "Does anyone access their attic through an exterior door in the gable wall?"
A. Builders of energy-efficient homes do as you suggest all the time. I addressed the issue in my article, "All About Attics," in which I wrote, "Some energy-conscious builders argue against attic hatches — they prefer to install an exterior access door in a gable wall, to prevent homeowners from entering their attic without an extension ladder..."
A photo of a house with a gable-mounted attic access door (and the required extension ladder) is shown below.
.
We did this at our house and it has worked out well. Attic with roof trusses, ceiling drywall is a very well sealed air barrier and tons of cellulose insulation on attic floor. I would also consider skipping soffit/ridge venting and just do gable venting.
One side of the house is a smaller fixed gable vent and the other side is a larger hinged gable vent:
http://www.customgablevents.com/Hinged-Gable-Vents.html
We built a small platform just inside the hinged vent and built a simple walkway down the attic (all above the cellulose). Two photos attached, each side of the house.
I would like to see how the walkway above the insulation is supported
micheal_obrian,
Depending on the truss layout I have built them two ways.
- Attach 2"x10" x however high your insulation is to the side of each bottom chord and run a 2"x10 on top as a catwalk.
- Attach 2"x4"s horizontally on each truss between the webs and run a couple of 2"x8"s on top.
Make sure your insulation contractor knows your attic access is in the gable wall. When our insulation contractor couldn't find an access in the usual places, they created an access by cutting a big hole in the ceiling drywall. Then, the drywall contractor had to be called back to fix the hole, the insulation contractor had to be called back to insulate the area over the repaired hole, and finally, the insulation contractor had to be called back a second time to fix the crappy job they did insulating the area over the hole the first time.
Martin, it's almost unheard of locally in my area. Glad to hear it's possible.
Ouch, Reid! Sorry you had that experience, and thanks for the heads-up. Brian, nice photos! Good suggestion about the platform and walkway. Thanks for the link. I wasn't able to find hinged gable access panels locally.
Debra,
Q. "I wasn't able to find hinged gable access panels locally."
A. This type of access panel (or access door) can be built by any carpenter. It's not something that you pick up at a lumberyard.
I couldn't find it in a quick search, but I have recollections of a previous discussion on this topic where an experienced hand suggested talking with your truss manufacturer about building supports for an elevated walkway into the trusses.
Congratulations for thinking of this sort of thing at the design stage.
I ended up going this route. Basically used an attic truss with a webbed floor. The webbed floor truss gives me a raised heel, and something to place the subfloor on. Worked out well.
Resurrecting this a bit with a twist. Only part of our second story will have an attic. The rest is vaulted ceilings. Because of the location of the attic floor (in the bathrooms) pull down stairs can work but just impractical and not wanted. Can this outdoor solution be implemented indoors? Is there a solution out there that has the ladder built into the door similar to pull down attics? Is there some other solution?
The attic hatch doesn't need to have stairs attached. The only time stairs make sense is if you're going to put a floor down in the attic and use it for storage. This was common decades ago, but doesn't make much sense with trusses and modern insulation depths.
A much better approach is to make a well insulated and air tight hatch panel.
What I like about this is that it reduces the temptation to put HVAC equipment up there in the future.
I would also check with the building department as to whether there are any access requirements to the attic needed by the fire department.
rockies63 makes a good point. My architect insisted the building code required an interior hatch. I wanted to use a high-end storm door.
blountwood,
The IRC says attic access must be "readily accessible", and gives the minimum dimensions for the opening, but I don't see any language that prohibits it being located on the exterior. This is something that is done fairly regularly.
Just ordered my hinged, sealed gable vent from Custom Gable Vents (https://www.customgablevents.com/). It isn’t actually a vent, of course, just made to look like one. They offer stock and custom sizes, hinged on either side. The one I ordered is for a conditioned storage attic over new shop building. It comes with a nail flange for mounting. I’ll apply rigid foam board to the inside of the “vent.” If you’re curious, give them a call. The fellow I talked to was knowledgeable and helpful
Malcolm, Unfortunately, just because something is or isn't mentioned in the IRC code doesn't mean that a local building inspector (or department) will allow it. I'd always run any design ideas past them first before investing a lot of time and money on something "different".
rockies,
Building codes are for the most part prescriptive. If the requirements are laid out, as they are in IRC 807.1, they may be superseded by other codes which are enacted regionally, but there really isn't any mechanism for inspectors or departments to ask for anything beyond them. So if you meet the requirements of whatever code is in effect, you are good to go, whatever your inspector's preferences.
I don't think locating attic access on gable walls is "different". It is done regularly (because it is code compliant), and companies sell doors for that purpose, including those designed to meet the envelope requirements in high wind areas.
I am planning on doing the same thing. I have two separate attic spaces with a ceiling vault in between. I am going to either use a small custom-made door or a window that can be installed in reverse to accomplish this task.
I've got a house where I do this. It's not an issue at all really. The access door is above the insulation so there is no reason for it to be sealed tighter than to keep out bats and varmints. It's actually not a door at all but there was once a window there but I had to break it out to gain access after a contractor sealed up my access from the interior. I replaced it with a piece of plywood with a gable vent to complement the roof vents. The door/window/access is above a porch so I just have to get a ladder to get on the porch to gain access which is rarely if ever so it's not an issue at all really. I just added it recently when I needed to do some detective work on a wire to a receptacle.