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HomeMy WebLinkAbout~Master - Special Meeting of the Ames City Council 10/27/1994MINUTES OF THE SPECIAL MEETING OF THE AMES CITY COUNCIL AMES, IOWA OCTOBER 27, 1994 The Ames City Council met in special session at 5:30 p.m., October 27, 1994, in the City Council Chambers, in the City Hall, 515 Clark Avenue, pursuant to law with Mayor Pro Tem John Parks presiding and the following Council Members present: Brown, Campbell, Hoffman, Parks, and Wirth. Mayor Curtis and Coun. Tedesco were absent. Present from the Building Code Board of Appeals were Harold Pike, William Bossenberger, David Delagardelle, and Bob Friedrich, Jr. WORKSESSION ON PROPOSED BUILDING CODE CHANGES: Building Official Jeff Pearson said the Building Code Board of Appeals has met with the Home Builders Association and concrete contractors to discuss proposed changes to the "Foundations" section of the Building Code. It was noted the Inspections Department does not currently perform foundation wall inspections, but it is assumed homebuilders follow the Uniform Building code (UBC). Mr. Pearson presented a videotape of a restaurant currently under construction, and distributed photographs of other examples to illustrate concepts of steel-tied foundations. Harold Pike, Building Code Board of Appeals, discussed various foundation forms, and explained how the UBC provides guidelines for engineers, architects, and inspectors. He said the Inspections Department and the Building Code Board of Appeals were asking that the current Code be enforced by requiring a foundation wall inspection so citizens have assurance their foundation is of the same consistent quality as the rest of their home. There was discussion of reports of failures, whether those failures occurred in homes with poured concrete foundations as well as in homes with concrete block foundations, and what age homes were experiencing failure. Mr. Pike said he had seen some failures in concrete block, but personally had not seen any in poured concrete. There was discussion regarding whether poured concrete homes had been built long enough to experience failures. There was discussion of how water during periods of heavy rains and flooding creates additional pressure on the walls of a home, and how soil conditions affect moisture retention. Mr. Pike noted the UBC provides latitude in requiring that each structure at a building site be built according to conditions, and spelled out specific guidelines for different types of soils. Coun. Wirth asked whether enforcing the Code meant homebuilders would have to use steel rerods if not warranted by soil conditions. Mr. Pike said if not warranted, the rerods would not be required. Coun. Parks asked the financial impact to the City of required foundation inspections. Mr. Pearson said based on the number of new homes built in Ames last year, Staff estimated required foundation inspections might add 150-200 inspections per year. He said current staff levels were capable of handling an additional 50 inspections each, but if building activity increased significantly, additional staff might be required. Coun. Parks asked the financial impact on housing costs, if conditions warranted rerods be used. Mr. Pike estimated a maximum additional cost of $400 for a $40,000 home, and said the additional cost was primarily due to the cost of steel. There was discussion regarding whether there was a need for different criteria for residential buildings versus commercial, and Mr. Pike noted commercial buildings generally involved architects and engineers, whereas residential buildings did not. Tom Donner, President of the Ames Home Builders Association, said the Home Builders felt a common ground needed to be reached so all homes were built of the same quality. He said the wished to achieve a balance between cost of improvements and necessity. He said the Building Code Board of Appeals' proposal would result in an average additional cost of $500-$800 per home. He explained the Home Builders' request for the ability to relax the UBC for one- and two- family dwellings, to have rebar 24" on center each direction, with verticals "dropped in" as the walls are poured, rather than using the pre-tying process. He said that solution would provide a means of controlling costs while insuring against catastrophic failures later on. He said the fact that the UBC provided latitude for differing soil conditions was not a valid point for discussion of the Ames area, due to the uniformity of soil conditions here. He said the Home Builders were in agreement with the proposed requirement for foundation wall inspections, however, and felt inspections would help increase the safety factor. He noted he had previously supplied Council with information he'd received from discussions with building officials from other major cities in Iowa regarding inspections and specifications for foundation walls. Coun. Hoffman questioned the validity of comparisons with other cities due to variations in soil conditions throughout the state, and Coun. Brown agreed. Mr. Donner said a cross-section of the entire state had been used in the survey and the majority of soils used in the comparison would be similar. Coun. Hoffman noted several Council members had toured a construction site to view the process of pre-tying reinforcing steel, and the process appeared to move quickly. Mr. Donner said most of the poured foundations were done by companies other than the builders themselves. He described the process used by foundation companies and said interrupting or changing that cycle would affect costs. adding 1/2 - 3/4 day to the construction timetable. Coun. Brown expressed concerns about structural stability if vertical rerods were "dropped in" to poured concrete as opposed to being pre-tied. Mr. Donner said while the benefit of pre-tying was to assure placement, it did nothing in terms of generating strength. Coun. Brown said accuracy of placement would affect structural stability, and Coun. Wirth agreed. Mr. Donner said he did not feel there was a problem in locating the rerod correctly within the wall using the drop-in process. William Bossenberger, Building Code Board of Appeals, discussed the importance of the definition of "failure," saying to some it may mean simply a crack in the wall that allows moisture to come through; to others, it may mean the loss of a wall. He said he sees very few of the latter. He said at this point, the majority of the failures are in homes 15-20 years old with concrete block walls. He said failures are just starting to be seen in poured concrete walls. Mr. Bossenberger explained how the backfill placed around the outside of a home when it is built is generally not compact, and the lateral pressure on the wall is at its lowest level. He said the backfill material compacts and settles over the years, and if moisture from clogged gutters and non- extended downspouts surrounds the foundation wall, the water pressure adds to the pressure on the wall and failures begin to occur. He said such failures were progressive. Mr. Bossenberger discussed UBC requirements and restrictions, and steel-reinforcing versus thickening walls to combat lateral pressure. He said the UBC specifies looking at the particular conditions. Mr. Bossenberger discussed backfill materials and said using granular materials provides the best solution, as it reduces the lateral force on the wall as well as preventing water from entering the basement of a home. He said however, the Building Code Board of Appeals felt that option would be more expensive than the steel reinforcing. Mr. Bossenberger discussed the "drop-in" method of reinforcing versus pre-tying, and said the Board's concern was that the location of the steel reinforcement was very important. Coun. Campbell asked the cost of foundation repair if failures do occur, and Mr. Bossenberger said repair costs can run from $2,000-$17,000 per house. There was discussion regarding the amount of reinforcing used in the reported failures, and whether it equalled the amount of reinforcing the Home Builders were proposing be used. Mr. Bossenberger said it was difficult to determine the depth and size of the reinforcement used in instances of failure, but the location of the reinforcing could be determined by using a magnetic probe. Mr. Donner said the Home Builders Association's alternative of using a 1/2-inch rebar on 2-ft. centers vertically and horizontally with the vertical rebar "dropped in" during the pouring of concrete, would result in a considerable improvement on the current standard practice for poured foundations, i.e., verticals on 6-ft. centers. He said in addition, the Home Builders were asking that foundation wall inspections be performed to ensure uniformity. Mike Dalton, 1304 Idaho, said he was employed by a construction company in Jewel, Iowa, which made concrete structures throughout the state, and had a foundation company doing work in Ames. He said the poured foundations his company uses are 7 5/8" thick, with vertical bars 4 ft. on center, and 2 ft. horizontally. He said adding a bar every other foot would not appreciably affect the cost of those foundations. He said he felt anything less than what his company was currently using as standards would be dangerous for future owners. He said they were supportive of what the City was proposing, but felt merely adding steel would not attack the real culprits of hydrostatic pressure and differing soils. He discussed soil conditions in this area, and said de-watering the site and providing good granular fill over good footing drains should be looked at. He said for the costs involved, he felt there should be a requirement in terms of soil preparation. He said adding more steel would not offset the need to do those things. He said requiring the steel reinforcement at 1 ft. centers would amount to an additional $1500 cost for the homeowner, who he felt should have the option of using that money elsewhere. Mr. Bossenberger said the point of the Building Code Board of Appeals' proposal was not to add more reinforcing to the walls, but to require that the conditions be considered. He said the American Concrete Institute, the One- and Two-Family Dwelling Code, and the UBC all require that if conditions indicate reinforcement is needed, it be placed at centers not greater than 18 inches. He said the Board's objection to the Home Builders' option is that it tries to assign one solution for every case. There was discussion of how this issue was being discussed in other jurisdictions, on both the local and national level. Dr. Charles Handy, Iowa State University, discussed the combination of soil and hydrostatic pressures, and the effect on foundation walls. Motion by Wirth, second by Hoffman, to direct Staff to provide draft ordinances of both the Building Code Board of Appeals' proposal and that of the Home Builders Association, for consideration at the November 1, 1994 City Council meeting. Vote on Motion: 5-0. Motion declared carried unanimously. COMMENTS: There were no comments. ADJOURNMENT: The meeting adjourned at 7:20 p.m. Sandra L. Ryan, City Clerk Larry R. Curtis, Mayor