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Transparency on a Zero set back lot line

S

Shams Gannon

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Joined
Sep 9, 2019
Messages
49
Location
Austin Texas
Here's a question for y'all... I have a client who wants to build transparency into the side of his building that faces an empty lot. Both lots are zoned Commercial Services and there is a zero setback between lot lines. Our city prohibits windows on a zero lot line, as there's nothing stopping the owner of the second lot to build directly up to our building, but does anyone know if transparency is included? We've been discussing using glass block or something else that will allow light in, but obscures any views in or out.

Thanks!
 
What code are you using? There is this in 2018 IBC:

706.1.1 Party walls. Any wall located on a lot line between
adjacent buildings, which is used or adapted for joint service
between the two buildings, shall be constructed as a fire wall
in accordance with Section 706. Party walls shall be constructed
without openings and shall create separate buildings.
Exceptions:
1. Openings in a party wall separating an anchor building
and a mall shall be in accordance with Section
402.4.2.2.1.
2. Fire walls are not required on lot lines dividing a
building for ownership purposes where the aggregate
height and area of the portions of the building
located on both sides of the lot line do not exceed
the maximum height and area requirements of this
code. For the code official’s review and approval, he
or she shall be provided with copies of dedicated
access easements and contractual agreements that
permit the owners of portions of the building located
on either side of the lot line access to the other side
for purposes of maintaining fire and life safety systems
necessary for the operation of the building.
 
Shams Gannon said:
Here's a question for y'all... I have a client who wants to build transparency into the side of his building that faces an empty lot. Both lots are zoned Commercial Services and there is a zero setback between lot lines. Our city prohibits windows on a zero lot line, as there's nothing stopping the owner of the second lot to build directly up to our building, but does anyone know if transparency is included? We've been discussing using glass block or something else that will allow light in, but obscures any views in or out.

Thanks!
Click to expand...


So what is the use of the building?
 
I am very interested in how you are complying with Table 602 and Section 705.8.

The AHJ should not need to "prohibit windows on a zero lot line"; the aforementioned sections of the Building Code should suffice to limit openings.
 
steveray said:
Unless you use 2018 IBC 706.1.1 and you need nothing.....
Click to expand...
That only applies if it is one building that extends across a property line, or the two buildings provide joint service.

You cannot build a single building right up to the property line and not protect the exterior wall by way of 706.1.1.
 
classicT said:
Take a look at Table 705.8. Even protected openings are prohibited where FSD is less than 3-ft.
Click to expand...
It wouldn't be an opening if it's a glazed curtainwall product to meet the required fire rating. They have 1- and 2-hour assemblies.
 
classicT said:
That only applies if it is one building that extends across a property line, or the two buildings provide joint service.

You cannot build a single building right up to the property line and not protect the exterior wall by way of 706.1.1.
Click to expand...
Connect them and it is one building....I guess that is irrelavent until the second "building" is built....Hope they like the view....
 
classicT said:
Take a look at Table 705.8. Even protected openings are prohibited where FSD is less than 3-ft.
Click to expand...


There are transparent assemblies that are tested as rated fire-resistive walls that happen to be transparent, so they are not classified as "openings" at all.

I once used that TGP system on a zero property line wall on a small office building a So Cal beach town. The neighboring property was unlikely to build for the foreseeable future, and though the transparent wall was extremely expensive, it was worth it for the owner to capture views of the nearby harbor.

From the TGP website https://www.fireglass.com/resources/fire-rated-basics/intro-to-fire-rated-glass-and-framing/ - -

"When specifying fire-rated glazing, it is crucial to understand the difference between fire-protective vs. fire-resistive glazing products (technically referred to as fire-protection rated and fire-resistance rated):

fire-protective-glass.jpg
fire-resistive-glass.jpg

Fire protective: Fire protective means the glazing defends against the spread of flames and smoke for its designated fire rating. Such materials include traditional wired glass, glass ceramics, and specially tempered glass. Fire-protective glazing typically is suitable where building codes allow “opening-protective” assemblies, including doors, sidelites, and windows. Such glazing is available with fire ratings ranging from 20 to 180 minutes, with varying impact safety ratings. Since it does not block the transfer of radiant and conductive heat, it is subject to area and size limitations under the applicable building code (typically the International Building Code – IBC, in the U.S.) and/or authority having jurisdiction.

Fire resistive: Fire resistive glass provides the same defense against flames and smoke as fire-protective glazing, but adds further protection by blocking the transfer of radiant and conductive heat. It is tested to the stringent fire-resistance test standards for walls, including ASTM E119: Standard Test Methods for Fire Tests of Building Construction and Materials and Underwriters Laboratories (UL) 263: Fire-resistance Ratings.

Given these performance benefits, fire-resistive glazing assemblies are typically suitable where building codes require an assembly designated “fire resistant” to enclose a space."
 
Last edited:
Shams ... you said the zoning is zero setback but you didn't say how far back your structure will be. You have to assume the worst case for the unbuilt neighbor, but you can control your side.
 
An architect I used to work for built a new office building less than 5 ft. from a property line. The part of the adjacent property next to the building was used for parking, and was likely to remain parking. His original plan was to put exterior sprinkler heads over the windows insted of using fire sash. The local fire safety reviewer pointed out that the annual inspection & testing costs for the sprinklers would be significant, and suggested buying an easement from the adjacent property owner. He did this, which increased the fire separation distance enough to allow the windows to be unprotected.
 
20 years ago we did "No Build Easements" and found out a lot of them where built on over the years. They where impossible to know where they where with out a title search or survey and we do not require those documents for issuing a permit
 
mtlogcabin said:
20 years ago we did "No Build Easements" and found out a lot of them where built on over the years. They where impossible to know where they where with out a title search or survey and we do not require those documents for issuing a permit
Click to expand...
I've rejected this approach on many occasions due to the implacability of ensuring the easement is maintained and not relinquished. Locally, relinquishment of such an easement would not involve the AHJ, as the easement is a private party agreement (i.e. the city is not a benefitted party). Therefore, to relinquish the easement, no action by the city is required. Just paperwork from both interested parties filed at the county. More headache comes in during property transfers and other land actions.

Only once did this approach get approved under my stamp, and it took an act of the city attorney, with the easement falling upon city owned property.
 
classicT said:
I've rejected this approach on many occasions due to the implacability of ensuring the easement is maintained and not relinquished. Locally, relinquishment of such an easement would not involve the AHJ, as the easement is a private party agreement (i.e. the city is not a benefitted party). Therefore, to relinquish the easement, no action by the city is required. Just paperwork from both interested parties filed at the county. More headache comes in during property transfers and other land actions.

Only once did this approach get approved under my stamp, and it took an act of the city attorney, with the easement falling upon city owned property.
Click to expand...
I think with more sophisticated property records and GIS records management systems, this doesn't have to be an issue.
There's not a lot I like about the byzantine approval process it the city of LA, but their computer records are pretty good. When you execute a no-build easement for the benefit of your neighbor it gets put on the property records of both properties, and it will pop up when the plans router does the initial city records search on your property.
 
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