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Frontage-public way & open space

Sifu

SAWHORSE
Joined
Sep 3, 2011
Messages
3,391
There are different interpretations of what constitutes frontage, but I think I get the intent (discussed on this forum before). I have stumbled (SHOVED) into another mess on an existing building. The snippet shows the original site plan. No dimensions, so I scaled them. The plan review shows a frontage increase of 33% in one location, and 37% in another (how or why 2 different numbers I can't say). The way I would figure it, it would be different than both. The original frontage uses 20' frontage width, and only 3 sides of the building (not sure which 3). Using 33% it would be slightly over the allowable area. To me it looks like all 4 sides have 30'. Am I missing something that would validate 20' width and only three sides?


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Oh boy, I knew that was coming. It is a tangled web.

Architect has a proposed remodel/change of occupancy. On the code analysis the project data lists the building as type IIB. I questioned this and subsequently found it is VB based on the original building review at birth. So I will request that be corrected. Among other, more important and existential issues is the incorrect construction type, which I decided to investigate in hopes to offer that the incorrect type was mostly irrelevant and required a minor correction, until I realized the allowable area of the VB building has been exceeded...based on their frontage calculation, even though they approved it on review. In looking at the original review I couldn't figure out why they used 20' and 3 sides. By my figuring they would go 30' on 4 sides and the building met and meets code. I just didn't want to call a lot of attention to an original mistake when I ask them to correct the construction type. Of no small matter, the original reviewer is now the CBO. I made him aware of my suspicion about the type and he is the one that found the original review, but not the frontage anomaly. This is mostly for my own knowledge, although it may come up so I am trying to prepare myself to say there was an error, but it isn't a major deal. I may keep my mouth shut if it doesn't come up, but I still want to check my own assumptions about frontage.

I don't want to say "fix your construction type" and call attention to the fact that based on the original review it shouldn't have been approved. So I could ask them to fix it and provide a new frontage calc., but that may cause medical emergencies. I would rather have the info I need before hand in case the issue blows up. It may be the CBO who blows it up without realizing he may have approved it based on data he could easily have checked. So then maybe I get to play good guy for a change by saying, a minor, inconsequential error occurred but it isn't a disaster.

FWIW, I see type IIB called on remodels all the time. A significant percentage are actually VB. When this is discovered I handle this by telling them to reanalyze it as a VB, or go through a process to revise the type. Few need to reclassify, even fewer do it. Part of that reclassification means figuring out what has happened in there since the building was born, and that gets ugly.
 
So going to a higher hazard? If not let it lie....

1011.6.2 Height and Area for Change to an Equal or Lesser-Hazard Category


Where a change of occupancy classification is made to an equal or lesser-hazard category as shown in Table 1011.6, the height and area of the existing building shall be deemed acceptable.
Going to a higher hazard; from B or M (they did not provide me with the previous classification, as I have asked but I know it to have been one or the other) to A2, so either from a level 4 or 3 to a level 2. Among the other issues, the architect apparently doesn't know of the existence of the IEBC. I made the comment to use the IEBC on the first go 'round, then tried futilely to explain that it is 100% the job of the architect to do this work and why to the town officials. I believe the height and area are fine if the frontage is done correctly, so if it comes to compliance I think all I'll need is a better area and frontage calculation. I believe it meets code as is, even if the documentation of it is wrong, so if it comes up that may be the salve I can apply to the situation. I really don't think this is going to be a big problem since the lack of sprinklers looks to be a more existential issue.
 
Unless you have the original drawings to compare what was used for lot lines by the original DP to determine the lot frontage increase it would be difficult to see why they did what they did.

If this is in a commercial complex sometimes building lot lines will move to match the cross easements for driving and parking that are shared uses within the complex after full development is complete.
 
Was the original construction approved under the previous code, which had a much more complex calculation for allowable area increase?
If so, maybe there’s some diplomatic way to ask them to restate the area according to current code.

I recently came across a IIIA building where the CBO had mistakenly approved removal of the rated ceiling membrane years ago, without checking if it would work as type IIIB. Luckily, the new code works out slightly more favorably for the yard increase - just enough that it will all work out as a IIIB under current code.
 
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