Replacement Windows on Lot Line

[Mech]

2009 IBC

Existing multi-story building whose exterior walls, with operable wood framed windows, are built on the side yard property lines.

3404.1 General. Except as provided by Section 3401.4 or this section, alterations to any building or structure shall comply with the requirements of the code for new construction. Alterations shall be such that the existing building or structure is no less complying with the provisions of this code than the existing building or structure was prior to the alteration.

Am I correct in assuming the existing windows can be replaced with operable non-fire rated windows, provided the areas are not increased?

Can they be changed to act as mechanical air intakes or exhausts? I would think they cannot.

Thanks in advance.

 

[mtlogcabin]

The IEBC seems to agree with you unless there is a change of occupancy

See definition

CHANGE OF OCCUPANCY. A change in the purpose or level of activity within a building that involves a change in application of the requirements of this code.

912.6.2 Exterior wall rating for change of occupancy classification to an equal or lesser hazard category.

When a change of occupancy classification is made to an equal or lesser hazard category as shown in Table 912.6, existing exterior walls, including openings, shall be accepted.

912.6.3 Opening protectives.

Openings in exterior walls shall be protected as required by the International Building Code . Where openings in the exterior walls are required to be protected because of their distance from the property line, the sum of the area of such openings shall not exceed 50 percent of the total area of the wall in each story.

Exceptions:

1. Where the International Building Code permits openings in excess of 50 percent.

2. Protected openings shall not be required in buildings of Group R occupancy that do not exceed three stories in height and that are located not less than 3 feet (914 mm) from the property line.

3. Where exterior opening protectives are required, an automatic sprinkler system throughout may be substituted for opening protection.

4. Exterior opening protectives are not required when the change of occupancy group is to an equal or lower hazard classification in accordance with Table 912.6

 

[Mech]

There is a proposed change of occupancy, but not in the area with windows on the lot line.

 

[mark handler]

Were the windows, on Lot Line, permitted?

What is on the "other side, of Lot Line? PRoW?

I typically require rated or fill in.

 

[steveray]

Are they separating the changed area?

912.1.1.1 Change of occupancy classification without separation. Where a portion of an existing building is changed to a new occupancy classification and that portion is not separated from the remainder of the building with fire barriers having a fire-resistance rating as required in the International Building Code for the separate occupancy, ********the entire building shall comply with all of the requirements of Chapter 8 applied throughout the building for the most restrictive occupancy classification in the building and with the requirements of this chapter.

912.1.1.2 Change of occupancy classification with separation. Where a portion of an existing building that is changed to a new occupancy classification and that portion is separated from the remainder of the building with fire barriers having a fire-resistance rating as required in the International Building Code for the separate occupancy, that portion shall comply with all the requirements of Chapter 8 for the new occupancy classification and with the requirements of this chapter.

 

[Mech]

Were the windows, on Lot Line, permitted?

Building is from the 1920s, so I am guessing they were legal.

What is on the "other side, of Lot Line? PRoW?

There is another building on the other side of the lot line. It looks like back in the day, there was a fire escape from the taller building down to the lower building's roof. Those openings have been blocked shut. Means of egress is being updated.

Are they separating the changed area?

Yes, they will be separated.