Someone told me they think windows have to be 30" to be code-compliant, I'd be curious if anyone happens to know whether that is code compliant in NYC

You are the owner ... and you are in NYC. Call the code department and ask them.

Normally, "grandfathered" means that an existing thing is OK, but any new stuff has to comply.

You seriously need to call a contractor who has worked in your area.

I don't know if the codes mention a minimum width, but in most historic neighborhoods and buildings, other dimensions are grandfathered in. If it were my house, I wouldn't want a door into the backyard from a dining room--it creates traffic problems and makes the room subject to far more use than before, which will cause more wear to the floors and other finishes .

Your best option is to convert the window in the kitchen--it is 31", and is a more logical entry point without overly increasing traffic. My side and rear doors are both 31" in my 1908 house, only the front door is 36".

And please--do not put in a metal screen/storm door! :)

The Residential Building Code as I understand it requires One entry/exit door to be a minimum clear size of 36" wide by 78" high in a single- or two-family dwelling. Other doors are not required to meet this minimum. This door also goes out to a private deck, which may make a difference. I don't imagine that NYC can be more strict than most municipalities when it comes to minimum sizes with code in existing structures even with remodeling. I do not live in, but frequent NYC and friends who live there have the narrowest hallways, the narrowest door openings, the smallest bathrooms and the least "active" ventilation systems in kitchens and baths of any city I have been in, in the US.

I would not recommend putting the door in the work triangle of the kitchen.

Okay, I don't get the not putting a door in the work triangle of a kitchen--almost every kitchen I have ever seen has a door to the outside as well as doors to other parts of the house...my kitchen has four doors: one to the entry hall, one to the diining room, one to the pantry, and one to the back porch...as well as an average height late victorian window. I have never had a problem cooking and having a back door in the same room--if someone comes in, they go around me.

Just to note, my kitchen is about 11'x12', the sink and stove are on opposite walls, and the fridge lives in the pantry about six feet from the stove.

"Okay, I don't get the not putting a door in the work triangle of a kitchen--almost every kitchen I have ever seen has a door to the outside as well as doors to other parts"

In this case the entire kitchen area is 7 feet +/- which includes two runs of counter and a 3 foot +/- work aisle only, as a galley with the door at the end. The deck is to be used for entertaining and the doorswing is into this 3 foot aisle. A 3 foot work aisle is minimum for a single person, or perhaps two working side by side. This means people going in and out from the deck will be squeezing by at best and there will be interference with cooking. There is more space for the door to open (and be left open) into the dining side of the kitchen. In a kitchen not so narrow, the door there would not have as much negative impact.

I intend for the door to outswing to the outside but then again - downstairs we have a deck off the dining room and actually the interior door swings in and the storm door swings out, so perhaps that is better in which case we might do better with the door off the dining room. A possible contractor pointed out that while the window pane itself is 29", if we put a door on the outside that frame opens much wider, 35" or so, so from the outside we don't have the same issue. I guess we hire the contractor, make sure that the contractor knows that the heck they are doing, and figure it out from there. And I'm not designing the kitchen until the contractor figures out how to open up the window to a door and which way the door swings, and we can work around that. I'm gunning to design the kitchen layout etc. but just have to wait.

Are you sure you're even allowed to remove that window and change the exterior? That's such a shame to do that. You'd be better off putting a door beneath the stained glass (although it kind of looks like there should be (or used to be) a window there, too). But I'd also be too afraid of ruining the bricks outside (or, if it's really a "brownstone," the stonework).

The door has to swing inside for fire safety reasons so that the exit could never become blocked by something on the outside.

Kevin MP, I tend to agree with you. I'm only putting a door off the dining room if the trim stays which probably means putting the door off the outside. I've gotten very mixed feedback from possible contractors about whether the door off the dining room could be built from inside or outside.

I love the idea of a door built from under the stained glass window but the deck design doesn't go across the width of the rear of the house - it only goes as far as the dining room window and the layout would accommodate a kitchen door or near dining room door but not a middle or far dining room door. And it would be much pricier to bust through the wall, bricks etc to create a new opening entirely.

How tall is the window? I have been in a couple old houses where an English basement window or a back window to a deck was converted from a double hung sash window to full inswinging casement window that was large enough to get out onto the deck or patio but not exactly a full sized door. Of course this was done when the floor of the patio or deck was higher than the window inside.

If this is not considered an egress door it may not need to meet the inswinging requirement for emergency egress. After all it was a window and could stay a window, which does not allow the same egress as a door to begin with.

The window is 77" for just the window part and the sill starts at least 24" above the floor, so the window is at least 7.5' tall from floor to top of frame (the ceilings are very high on that floor, ) we'll need an exterior storm door of some kind, and can have an inswinging door that's a normal door with as many glass panes as possible to let in light.

I keep going back and forth on where the door should be. It really should be in both places - kitchen for our convenience, and dining room for when we entertain - but that's not practical or affordable right now, so I have now picked, kitchen. it may be a challenge to get around people when we entertain but hopefully it's the worst thing about having people over, and we'll make it work.

Following up again - I decided on one fiberglass/glass outswing door to the deck from the kitchen, with a retractable screen door on the inside, this way the door off the kitchen isn't as much in the way as an inswing door would be - and have decided to have a kitchen ISLAND rather than a peninsula so people can go from dining room through tail end of the kitchen and out the door without getting in the way of the island/fridge/stove area (the sink will be closest to the door and will be a double sink, so people can come in and grab or drop stuff and get sink access easily). We're doing a temporary kitchen for now with older appliances borrowed from our former tenant's kitchen in part, then designing the cabinets/countertop/backsplash part once we're up and running and have a new tenant bringing in income. If we find this is not workable we can fix it in the final kitchen.

As for layout generally, I finally got the idea to meet lots of neighbors with the same general house, and boy do the layouts differ. But most other houses I saw had the door off the MIDDLE of the dining room, having converted a window between the 2 bay windows, to a door. Well, we don't have a third/middle window, so we would literally have to create a door out of the brick exterior adding thousands to the project, and requiring a wider deck. I seriously thought about it but adding $15,000 to the project would just be too much so we didn't do that. But no one had a door off the side window on an angle - it is either middle of the dining room or off the kitchen. So I chose kitchen. Wish I'd thought to check "precedent" a year ago, would have changed this project big-time! Live and learn.

Thanks all for your feedback, I stumbled on this post when looking for something else (retractable screen door) and figured I'd post pictures of the end result - it turned out great - I'll post a picture of the final kitchen and another one of the door, I'm very happy with it, now we just need a good screen door to keep out mosquitos soon

And here is a photo of the installed door to the new deck

I am so glad you are happy with the change. It looks beautiful.

My sister put up a screen that slits down the center and connects with magnates to keep it closed. It is a set of french doors to their deck, so a screen door isn't an option.

Wow, that came out nice!!!

Nice; if you saved the old window parts and the pile of brick, it could well be put back, if ever one wanted to. And you kept the wood floor, so bless you!
Casey

I stumbled on this old post. @dreamojean, would you have any reference for the contractor you used. I would be interested to do a similar project in my nyc home