Modular Building Setbacks

[classicT]

When considering the placement of a semi-permanent (180+ days) modular building, do the minimum setbacks of Table 602 apply?

Proposed location of 435sf modular is 4' from exterior wall of existing 41000sf Type B Occupancy (on the same lot). No fire separation required between occupancies, both are Type B.

2015 IBC w/ WA State Amendments

 

[Builder Bob]

Depends on how your state handles modular buildings. In our state, new construction (modular or traditional) cannot place an existing building into a state of non code compliance for which the existing building was constructed.

Your state/ municipality/ AHJ may differ

 

[SCBO1]

Not sure why a temporary or semi-permanent building would be allowed to be closer than the code allows. The building could still cause issues with the permanent building and depending on its placement could hamper fire fighting activities if either building were to go up in flames.

 

[Paul Sweet]

Is this a manufactured (trailer set on blocks) or modular (on a regular foundation) building?

Is it for temporary offices while the existing building is renovated?

 

[classicT]

Manufactured trailer set on blocks with tie-downs. Temporary offices to accommodate increased staffing.

Not a temporary job shack for a remodel, looking at multiple years of use.

 

[Mr. Inspector]

Maybe this exception can work for you under 705.3 Buildings on the same lot:

1. Two or more buildings on the same lot shall be
either regulated as separate buildings or shall be
considered as portions of one building if the aggregate
area of such buildings is within the limits specified
in Chapter 5 for a single building. Where the
buildings contain different occupancy groups or are
of different types of construction, the area shall be
that allowed for the most restrictive occupancy or
construction.

 

[classicT]

Maybe this exception can work for you under 705.3 Buildings on the same lot:

1. Two or more buildings on the same lot shall be
either regulated as separate buildings or shall be
considered as portions of one building if the aggregate
area of such buildings is within the limits specified
in Chapter 5 for a single building. Where the
buildings contain different occupancy groups or are
of different types of construction, the area shall be
that allowed for the most restrictive occupancy or
construction.

Had the same thought, but modular is Type VB, and the existing IIB is 41000sf; therefore we would be well over.

My thought, as of now, is that a minimum of 20' separation is required (imaginary lot line with 10' setback for each building). Not sure that I totally believe that to be necessary, but that is what the code leads me to.

 

[Francis Vineyard]

In accordance with the existing building code "An addition to a building or structure shall comply with the International Codes as adopted for new construction without requiring the existing building or structure to comply with any requirements of those codes or of these provisions, except as required by this chapter."

An addition shall not create or extend any nonconformity in the existing building to which the addition is being made with regard to accessibility, structural strength, fire safety,

With modular classrooms I require it meets the current code for fire-separations i.e. 10 ft. The existing school can use the fire-separation distance that was in effect when it was first occupied, 5 ft.

This reduces the separation to 15 ft. between structures.

 

[Mr. Inspector]

i don't know how you can call the modular classrooms that are separate buildings additions.

 

[Francis Vineyard]

i don't know how you can call the modular classrooms that are separate buildings additions.

Consider it a reference for an addition to an existing building on the same lot. Do you know of another provision in the IEBC that would be applicable?

[A] 104.1 General. The building official is hereby authorized and directed to enforce the provisions of this code. The building official shall have the authority to render interpretations of this code and to adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures shall be in compliance with the intent and purpose of this code. Such policies and procedures shall not have the effect of waiving requirements specifically provided for in this code.