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two duplexes or a four plex

Francis, Buelligan is asking about a different project than the OP (retire09).

Buellgan, In answer to your question, Yes they qualify as 'townhouses' under the IRC.
 
I have what is essentially two duplexes
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This is confusing

I think you are saying you have a 4 unit Townhouse and can the common each wall between each unit be reduced to one-hour if all the units are sprinkled?

Answer: yes
 
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The above is how they are laid out. They for all intent and purposes are sold and marketed as "duplexes" and look more like that than the traditional "3-story" townhouse. But by my understanding it falls very clearly in the IRC "definition" of a townhouse.

So let me pose this question. Considering the separation and lot lines could this still be submitted under R-3?
 
mtlogcabin said:
This is confusingI think you are saying you have a 4 unit Townhouse and can the common each wall between each unit be reduced to one-hour if all the units are sprinkled?

Answer: yes
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Yes that is what I am saying. Just not sure because of the "Marketing Term" used. They are being sold as "Villas" and even using the term "Duplexes". I guess because they are not your typical skinny 3-story townhomes they are more like 4 attached ranchers if you will.
 
Well I'm (was) confused; I thought a duplex is another name for 2-family dwelling. Townhouses are 3 or more attached single family dwellings.

Four attached ranchers would be under IRC and also Chapter 11 of IBC; unless they've deleted R320
 
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Remember to qualify as a townhouse the fire rated wall has to extend from the foundation to the roof deck and parapets need to be installed or the exceptions need to be followed.
 
You do not have duplex townhouses. You have two, R-3, two dwelling unit buildings separated by a 2 hour fire wall.

You can call them Villas but they are technically not townhouses or duplexes. They are compliant with the IBC and do not qualify for construction per the IRC.

It all makes perfect sense if you don't think about it. :)
 
Trail braked and didn't see it coming, now off in the sand pit

Post #51 shows 4 lots and 4 homes with 2hr firewalls on property lines = 4 townhomes. Marketing terminology is not accurate, code definitions are applicable to code discussions.
 
retire09 said:
You do not have duplex townhouses. You have two, R-3, two dwelling unit buildings separated by a 2 hour fire wall.You can call them Villas but they are technically not townhouses or duplexes. They are compliant with the IBC and do not qualify for construction per the IRC.

It all makes perfect sense if you don't think about it. :)
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Why would they not "technically" be townhomes? In this case they meet the definition posted above EXACTLY - 3 or more attached with yards on 2 sides.

I absolutely understand that "Marketing terms" are not relevant to code but it gets a little worrisome when these look like and are sold as attached "Duplexes" even if they call them "Villas". I felt comfortable with my decision to consider them "townhouse" by code definition, regardless of any "terms" used.

The reason this is an issue is that our state adopted 2009 with an amendment to 313 for One and Two Family dwellings that gives alternatives to sprinklers. But they left Townhomes out of the amendment! This contractor is upset because as he states, "these are not townhomes". But I got him to understand that it is not a One and Two Family dwelling and that it is either a townhouse or he can use the IBC R-3. Either way he has to sprinkle these units.
 
A townhouse is attached single family with a fire wall between each. A duplex is detached two family.

It is my understanding, you have two units on each side of a fire wall.

Not being single family, it is not a townhouse.

Not being detached it is not a duplex.

It is still an R-3 per IBC
 
I have not seen a drawing; but if all individual dwelling units have the required fire wall separations; they are townhouses.

If the fire wall is only provided at every other unit they are not.
 
The ORIGINAL POST was about 2 duplexes on adjoining lots with a 2 hour wall.

BUELLIGAN's post is about a DIFFERENT scenario.

OP is NOT townhouses, Buelligan's are.
 
JBI said:
The ORIGINAL POST was about 2 duplexes on adjoining lots with a 2 hour wall. BUELLIGAN's post is about a DIFFERENT scenario.

OP is NOT townhouses, Buelligan's are.
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Exactly! Two different scenarios...two different answers.
 
Thanks guys!

One question though. In the OP, would the duplexes on either side of the "center" wall be required to be separated by 2- hour as well? or did I miss something, like them being stacked or are they all on the same lot maybe? Just curious
 
Buelligan, The OP had duplexes on adjoining lots with zero lot line clearance. Honestly, I'd have to check the IBC for required rating and limitations, but I think the 2-hour wall and limited mechanicals would comply depending on construction type (sprinklers would be a given for a new R occupancy in IBC).
 
The two unit buildings are separated by a two hour fire wall the individual units are separated by the required one hour between dwellings.
 
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