January 22, 2008
Right Sizing Committee
C/O Williams Elementary School
20691 Williams Highway
Williams, OR 97544
Note: The numbers Mr. Pingle refers to are the item numbers from the original TRSD/Crow/Clay cost estimate. They went on to revise the estimate (upwards!) and changed the item numbers around.
Re: Structural Observation of School Buildings
Dear Committee Members,
Rebecca Hinson, a concerned parent, asked me to review the Williams Elementary School Facility Maintenance Recommendations and Cost Estimate, January 2008, prepared by Crow/Clay & Associates, Inc. and to perform my own structural observations of the school buildings. I have also reviewed notes from Robert Morgan (a teacher at Williams) with his perspective on events as they have happened. My site observation was not exhaustive; however, I did look around the entire basement area, in the attic of the gym, in the restrooms and around the exterior of the buildings and parking lots and also spoke with maintenance personnel who were on-site. I am a registered Structural and Civil Engineer in the state of Oregon with over 20 years of engineering experience. My comments and opinions will focus mainly on the structural and civil issues and where possible will reference the numbering from the Crow/Clay report.
Exterior #1: The basement flooding issue has almost nothing to do with the gravel parking lot. The roadside ditch has been re-constructed to prevent water from the ditch to enter the parking lot and contribute to possible flooding. Almost all of the water that enters the basement comes from underground up through the slab and the sump pump sumps. Adding impervious area (asphalt) to the parking areas can also create drainage issues and storm water quality issues. The existing gravel area appears to be in good condition and could continue to serve the school adequately with some minor maintenance. If accessible parking is an issue, those particular parking spaces only could be paved at substantial cost savings.
Exterior #2: The gym currently does have an ADA accessible entrance from the interior asphalt courtyard and the courtyard does connect to the parking area on the north side of the building. It seems that proper signing could easily direct people to appropriate parking spaces and into the gym and the rest of the school.
Exterior #3: If there are “several areas” where wind driven rain enters the wall cavities, why not just take care of those specific locations with proper maintenance and verify if there really is a problem or not, instead of assuming there is a problem?
Exterior #12: A ramp of this nature would destroy the look of the front of the school and would have to be at least 60 feet long because of the height and the required landings. There is an existing ramp in the rear of the school building that functions, even though it does not meet ADA standards.
Exterior #14: During my site visit, I inspected the roof structure and the Bowstring Trusses in the gymnasium. All of the rafters, blocking, bracing and the trusses appear to be in excellent shape. All the bolts I check were tight and I found no cracks, checks, deterioration or deformation in any of the wood members. There were a few spots where there had been a leak in the roof at one time, but the structural members have not been affected by it and appear structurally sound.It is true that the combination of three factors (changes to loading, analysis methods and timber stresses) results in an overstressed condition for most bowstring trusses. (See the attached article). The concern for this truss design and most of the issues with these trusses occur during very heavy and rare snow events. It is also true that this structure has been safely standing and serving its intended use for over 50 years and has experienced many heavy snow and severe weather events without incident and remains in very good condition. The local Lorna Byrne gymnasium roof collapse in 1995 and the history of bowstring trusses in general certainly does warrant concern and it would be prudent to consider upgrading or reinforcing the trusses at some point and until that time comes, continue to monitor the trusses as is being done now and be cautious of severe snow events. Exterior #15: The ditch work along the highway has already been done and most of the other work described is a huge waste of resources. The real problem with the basement flooding is NOT from surface water, it is from abnormally high ground water levels. It is my understanding that during these admittedly rare events, the water remains in the basement for only a couple of days. Many areas around the world routinely flood and much more often that what have to be dealt with here (Venice, Italy and New Orleans). The basement has concrete walls and floors and the only structural elements that could be damaged by water are the large wood posts. Having the bottom of the wood posts in water for a couple of days will not cause them to deteriorate as long as they are dried out again after the event is over, plus it is quite simple and inexpensive to check them and replace them if need be. The non-structural elements in the basement could be minimized, shelving could be changed to steel racks and mechanical equipment could be set 24”above the floor. A small back-up generator for the sump pumps would also help, but this issue of having some water in the basement several times in 25 years is not a structural or safety concern to the building.
Interior #3: The existing girls and boys restrooms could easily be made ADA compliant without having to expand the building by making changes to the stall configurations, sink enclosures and at the worst, relocating some plumbing fixtures.
Interior #8: Fire separation depends upon types of occupancy, materials stored and other factors that the Fire Marshall determines to be hazardous or dangerous. This may be a good idea, but is it absolutely necessary or required? In most jurisdictions, bringing existing structures up to current code and ADA requirements or upgrading structural components for seismic or other loading concerns is only required with a change in occupancy or use or an extensive remodel or addition. General maintenance and upkeep typically does NOT trigger these requirements. I have mainly addressed the issues that I have some expertise in and believe that with appropriate routine maintenance, this facility could continue to provide educational services to the community of Williams for many years to come.
If you need further assistance, please let me know.
Sincerely,
Scott D. Pingle, P.E., S.E.
08008Let1
