• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Deck, porch, patio, balcony?

Glenn

Glenn

Registered User
Joined
Nov 1, 2012
Messages
889
Location
Denver
I am asking for your opinion about the various terms used in the IRC to describe exterior walking surfaces: Deck, Porch, Patio, Balcony.

After 16 years of teaching deck codes and 10 years participating in deck code development, it is painfully clear that these terms are not used or interpreted consistently. I listened to testimony in the 2024 IRC hearings from respected professionals stating that because a certain code section said "porch" that it does NOT apply to "decks". Or if you are building a "porch" you would not use the "deck" section 507.

This makes ZERO sense to me.

Crazy as I am, I am already beginning to work on 2027 IRC proposals and dealing with this terminology is one of the lofty goals I am going after. I would like your thoughts and opinions of what these terms are and how they should be used in the IRC. Below are my thoughts. Please comment with yours.

Deck or Porch: From a code standpoint these are the same. "porch" is an older term. "deck" is a newer term. This is what my historical book collection has taught me. "porch" was often on the front of the house and often had a roof. Thus "porch roof" is also a common term. I see no need for the term "porch" in the IRC and believe all exterior, framed walking surfaces should be called "decks". If you disagree, please explain the "code implications" that should apply differently to porches than decks.

Patio: This term is less used in the IRC. I believe this is a walking surface created with materials that are supported entirely on grade. There are no structural applications from the code. However, should other code provisions for "walking surfaces" apply to patios? Such as safety glazing or stairs. What if a flagstone "patio" is adjacent to a 36 inch high retaining wall? Should guards be required when there is a "patio" vs when it's just grass? What do you call a "walking surface"? That's sort of another can of worms.

Balcony: I find this to only be different for structural design purposes. A "balcony" as might be commonly used to describe a small master bedroom deck is really no different than a deck, unless it is a fully cantilevered structure. I find the only reason to differentiate a balcony would be for prescriptive structural design purposes. I am bothered that historically balconies required a 60 psf live load. This was basically a safety factor of sorts for the concerns of the joists not being supported on one side. I find that a huge misuse of "live load". LIve load should be based on the anticipated loading by the occupant and nothing else. Occupants don't load balconies more than decks. What we need to do is create sufficient strucutural provisions to support a 40 psf live load on a balcony (cantilevered deck). That said, the 60 psf balcony provisions have been removed from the IRC a few editions ago. I still bring this up for discussion. The IBC and ASCE 7 require 1.5 the live load of the room served by a deck. So those documents already require all "decks" to be 60 psf in R occupancies. The IRC is still 40 psf and my opinion is that is sufficient.

I look forward to hearing your thoughts. Thank you in advance.
 
Last time I checked, porches were covered (roofed over) structures attached to a primary building, making them additions. A porch can be open on three sides but also can be enclosed. Not mechanically heated or cooled.
 
Just my two cents: When the term deck is used it seems to always be made of wood, built in such a way that it is permeable (drains freely), and has it's own connection to the ground to support gravity loads (at least a portion of the load). A porch could be built off of a deck, or it could be built off of a slab, or even off of grade, but anytime I hear porch I think of an exterior covering over a door. Could be enclosed or not, or adaptable, such as a "three season porch". When I think of a "balcony" I think of it as an element of the building. The entire gravity load is supported by the building and it does not have it's own connection to ground.

Thanks for asking! Great topic.
 
I agree on deck, porch & patio. I think one element of a balcony is that it does not have any exit, stairs, etc other than the way it’s accessed from inside the house.
 
Are you going to propose adding definitions for these items? I think it would definitely be a good idea, as we do not use the words consistently with a normal definition. IRC 201.4 says that terms not defined shall have ordinarily accepted meanings such as context implies. I typically use Merriam Webster's to determine ordinarily accepted meanings, and you can see that would not work very well at all.

From Merriam Webster:

Definition of deck​


2: something resembling the deck of a ship: such as
a: a story or tier of a building (such as a sports stadium)the upper deck
b: the roadway of a bridge
c: a flat floored roofless area adjoining a house

Definition of porch​


1: a covered area adjoining an entrance to a building and usually having a separate roof

Definition of patio​


1: COURTYARD especially : an inner court open to the sky
2: a recreation area that adjoins a dwelling, is often paved, and is adapted especially to outdoor dining

Definition of balcony​


1: a platform that projects from the wall of a building and is enclosed by a parapet or railing
 
Wood decks built on grade:
R507.1 Decks. Wood-framed decks shall be in accordance with this section. For decks using materials and conditions not prescribed in this section, refer to Section R301.

Everything else:
R301.1 Application. Buildings and structures, and parts thereof, shall be constructed to safely support all loads, including dead loads, live loads, roof loads, flood loads, snow loads, wind loads and seismic loads as prescribed by this code. The construction of buildings and structures in accordance with the provisions of this code shall result in a system that provides a complete load path that meets the requirements for the transfer of loads from their point of origin through the load-resisting elements to the foundation. Buildings and structures constructed as prescribed by this code are deemed to comply with the requirements of this section.

When considering a deck, patio, porch or balcony there is a specific example in mind. There is either an example in front of you or a proposed whatever it is. It is not confusing until they are all called decks.
 
I agree it's a little unclear now and am glad you're working on it.

Patios can be "attached" or a ways from a house, and can be roofed. When does a patio become a porch, or vice a versa, since concrete porches are not uncommon.

Can a deck ever have a masonry walking surface, or is it always light framed? And can a deck be roofed or does that make it a porch ( and only if attached to a house?)

I've lived in several houses with porches - roofed and open to exterior - not built of treated wood, and they have been fine after 100 years. I would not be in favor of all porches having to be built of pressure treated wood like R507 decks.

Is a traditional sleeping porch actually a balcony?

Just thinking about features like these in the half dozen buildings I've lived in, it seems to defy categorization, which a prescriptive code like the IRC depends on.
 
We only call them decks and covered decks here no matter what the applicant calls them. Fully enclosed porches we call additions or sunroom additions

Glenn, I like your definitions, how ever I have more problems with the difference between a deck and an exterior wood landing. Sometimes the landings are to small to put on 4 lateral load brackets.
But in the definition of a deck maybe it should say something about being sperate decks when they go around the corner to the side of the house or when they are on different levels because of the lateral load brackets requirements.

Also I had a post on here with questions about the 2015 IRC porch header tables that I posted once, had a hard time understanding it, this could use cleaning up. Maybe call it a open or deck roof beam table? Funny now I can't find it in the 2018 IRC. Where did they hide it? And why would a span table be different for porches than other beam tables?

I like the new footing tables in the 2018 IRC we just started using, I think they require too big of a footing for my rocky area but at least I have something to go by. Contractors hate them. We use to allow 12' snontubes. They don't make 14" sonotubes. But I would like to see a table like this for covered decks, landings, additions and buildings. I inspect a lot of small houses, covered decks and additions on piers.
 
Inspector Gift said:
Research the UBC for definitions of "Balcony". I don't believe that a balcony is only an exterior element. Many churches and auditoriums have interior balconies.
Click to expand...
Yes. I didn't say anything because this is IRC, but I try to remain vigilant in IBC changes because they can cause problems to assembly space balconies.

I wondered if a deck was a deck if it had direct stairs to grade but a balcony if not? They could otherwise look very similar.
 
Thank you for all the comments and I hope to see more. A few responses.

The terms used in the code should relate to the implications and applications in the code. I see no reason to call the walking surface a "porch" simply because a roof was built over it. Or calling it a deck, because it doesn't have a roof. In my first post, I provided terms and and explained them. This time, let me provide "descriptions as concerned by the code" and we can assign terms to them.

1) The code provides prescriptive design methods in 507 for "a wood framed elevated walking surface". If steel was used for joists, beams and posts, it's still fall under this category. If the decking surface is wood, composite, fiberglass, stone, or pavers it doesn't matter if it's on an elevated structure built with joists, beams and posts. If it is water tight or has a built in drainage system, it is still the same thing, unless such waterproofing qualifies as a "roof covering". Otherwise it's just cool gutters. This includes "framed elevated walking surfaces" that cantilever from the house, or any design of "framed elevated walking surfaces" that are engineered. A small landing falls under this, and NO, lateral load connectors should not be required. PLEASE don't let that unbelievably NOT THOUGHT OUT lateral load anchor from 2009 have any part of this discussion. That provision is garbage and based on nothing but fear. I'm biting my tongue so we stay on topic.

2) A walking surface supported entirely on grade. This could be a concrete slab at the front door. Flagstone out in the middle of the yard. There is nothing to "span", not even decking. There is essentially no structural system.

3) Decking spanning across members supported entirely. This is basically a sleeper system over a roof or the exception for footings in 507 when joists are supported entirely by grade. This is almost like #2 above, except "technically" the decking is still a spanning member.

-For structural provisions, these are the distinctions I believe the code should address.

-If you put a roof over any of these. Deal with the roof for the roof. It doesn't change the name of the floor. If you build a deck to also be a roof, then you have a roof and a deck and you must evaluate for both.

-If there is grade-level access or not, it does not change the applications above, thus should not change the term. The NEC deals with exterior door lighting by speaking directly to "access to grade" not by calling the surface by a "name".

- If we start enclosing these, what implications change? What hazard changes? Like a carport vs. garage? At what point is it enclosed enough that the code should address them differently

- If you make it a sunroom, it's a now a sunroom. If you make it an addition, it's now an addition.

And the big issue... codes that address "walking surfaces". In 2021 311 was changed to try to make it clear what "stairways" need to comply with code. I have been teaching this section and the feedback I get is it needs work. It is easy to understand that "non habitable attics and crawl spaces" do not need compliant stairs, but the deck part still gets inconsistent interpretation. That section says "deck and porch", as if there is a difference and so both terms need to be included. But it does not say "patio", as if there is a difference and it is not meant to be included. I assisted in creating that section, and to my understanding that was the intent. A "patio" (supported on grade) that is not "serving the house" (as in a front concrete "patio") does not need compliant stairs. This is meant to allow the casual landscape away from a house to not be scrutinized under 311.

Finally, words matter in a professional standard. I put a LOT of effort into teaching the public about the IRC. The public expects the words to matter. They expect that if one provision says "deck" another says "deck and porch" and another says "patio" that there is an intended difference.

Thanks for all the help. This isn't the only terminology proposal I am working on.
 
Glenn said:
This makes ZERO sense to me
Click to expand...
I agree. Any wood-framed structure whether a deck or porch that is exposed to the weather should be treated the same. No reason to use the word "porch" at all.
Glenn said:
The IRC is still 40 psf and my opinion is that is sufficient.
Click to expand...
Assuming this is specific to wood framed balconies. Some are cantilevered and some are not. Is this reduction to 40psf limited to IRC projects?
 
bill1952 said:
Does the presence of a roof over a walking surface change the design load - snow loads?
Click to expand...
I would say no because snow blows around.
But what if has walls with only open or screened windows and doors?
I think if it needs treaded lumber on the floor it would be the same as a deck. (Enclosed deck? But IRC 301.2.1.1.1 calls this a "Category 1 Sunroom" but the IRC does not define it as a "Sunroom" in IRC 202 Definitions.)
 
With 60 psf snow load, seems over the top to have to design roof and floor under it for that load. And having lived in houses with porches with roofs in snow country, I assure you that very little snow collects on the porch floor.
 
You must log in or register to reply here.
Top