Appeal 9710

R102.7.1 & R311.5.2

R102.7.1 Additions, Alterations or Repairs
The section reads in part: "Additions, alterations or repairs shall not cause an existing structure to become unsafe or adversely affect the performance of the building."

§: R311.5.2 (Stairways) Headroom
"The minimum headroom in all parts of the stairway shall not be less than 6 feet 8 inches measured vertically from the sloped plane adjoining the tread nosing or from the floor surface of the landing or platform."

Interior stair to basement to have not less than 6 feet 3 inches headroom at one area of the stair run.

The existing unfinished basement of the residence is being altered into habitable living space under two building permits (#2007-159545-000-00-RS & #2008-147075-000-00 -RS). The existing stair from the main level to the unfinished basement was badly deteriorated, unsound and had no handrail. Under permit #2007-159545, the existing basement concrete slab was to be removed and a new concrete slab poured. It turned out to be unfeasible to support and salvage the existing stair and pour the new slab. A decision was made to remove the existing stair at that time and reconstruct the stair with new materials after pouring the new basement slab.

Under the current building permit #2008-147075-000-00-RS, a framing inspection was called for to inspect the work in the basement. The City inspector raised the issue of the fact that now that the stairs had been rebuilt - they were no longer grandfathered¬in with the prior non-conforming headroom clearance. To address this problem, the Owner was instructed to file for a building code appeal.

The existing floor framing for the stair opening and the location of the walls at the main living level prevent a reconfiguration of the stair location, rise, or run so that the stair could come into compliance with current code. The rebuilt stair utilizes the same location, rise and run of the original stair assembly. The rise of the stair is 8" and the run is 10". With the addition of a post to one side of the stair, a beam intruding into the headroom clearance can be reduced in depth to increase the available headroom. This will create an improvement over the original headroom clearance that previously existed with the original stairs. Even with this modification, the best that can be achieved is a clearance of 6'-3".

Two mitigating factors that lessens the impact of this stair: At the rear of the basement is an external door 36"W x 78" H leading to an existing exterior set of concrete stairs 3'-6" in width. Also, the new bedroom being created will have an escape window complying with the provisions of §: R310.1 for Emergency Escape and Rescue openings.

Also, even though Appendix J (Existing Buildings and Structures) of the 2006 IRC was not adopted by the State of Oregon - §: AJ501.8.2 Stair headroom reads:
"Headroom height on existing basement stairs being altered or modified shall not be reduced below the existing stairway finish headroom."
This was an acknowledgement by the international code writing body that basement stairs cannot always be brought up to current code when altered or modified. Had Oregon chosen to adopt Appendix J, an appeal for these stairs would not be necessary. The language of Appendix J is reasonable and though not the law of the land, it is an indication of what is considered a reasonable compromise in these situations.

R311.5.1

R311.5.1 (Stairways) Width
The section reads in part: "Stairways shall not be less than 36 inches in clear width at all points above permitted handrail height and below the required headroom height. Handrails shall not project more than 4.5 inches on either side of the stairway and the minimum clear width of the stairway at and below the handrail height, including treads and landings, shall not be less than 31.5 inches where a handrail is installed on one side and 27 inches where handrails are provided on both sides.
Exceptions:

1. Where the floor is served by more than one stairway, stairways other

than the first stairway may have a clear width of not less than 30 inches. Any handrail may encroach a maximum of 4.5 inches into the clear width."

Interior stair to basement to have not less than 29 inches in width

The rebuilt stairs to the basement are limited to the width of the old stair assembly that it replaces due to the existing floor opening framing. The stairs will typically be 30 inches in width. However, at the bottom trea the width will be reduced to 29" to allow for the newel post. The stairs will have a ha drail on only one side.

Because there is the direct exit from the basement to the exterior which is served by the external 3'-6" wide set of stairs, the rebuilt interior stair can be considered a "second" stair and not the "first" stair, which would require the 36 inch clear width. As a second stair, the reduction from the required 30 inches to the appeal request of 29 inches at only one or two of the treads is a minor variation for the intent of the code and should pose no life safety hazard.