BUILDING CODE COMMISSION

Transcription

1 Ruling No Application No BUILDING CODE COMMISSION IN THE MATTER OF Subsection 24(1) of the Building Code Act, S.O. 1992, c. 23, as amended. AND IN THE MATTER OF Article of Regulation 403, as amended by O. Reg. 22/98, 102/98, 122/98, 152/99, 278/99, 593/99, 597/99, 205/00 and 283/01 (the Ontario Building Code ). AND IN THE MATTER OF an application by A.C. Houle, Principal, Morey Houle Chevrier Engineering Ltd., for the resolution of a dispute with Terry Davidson, Sewage System Inspector, Ottawa Septic System Office, to determine whether the repair of an existing Class 4 septic system, specifically with respect to the grain size of the imported sand filter material being used, provides sufficiency of compliance with the provisions of Article of the Ontario Building Code at 1376 River Road, Manotic, Ontario. APPLICANT RESPONDENT PANEL PLACE DATE OF HEARING A.C. Houle Morey Houle Chevrier Engineering Ltd. Manotick, Ontario Terry Davidson Manager Ottawa Septic System Office Bryan Whitehead, Vice-Chair Toronto, Ontario July 4 th, 2002 and August 8 th, 2002 DATE OF RULING September 4 th, 2002 APPEARANCES A. C. Houle, Principal Morey Houle Chevrier Engineering Ltd. The Applicant - via telephone conference Terry Davidson, Manager Ottawa Septic System Office The Respondent - via telephone conference

2 -2- RULING 1. The Applicant A.C. Houle, Principal, Morey Houle Chevrier Engineering Ltd., has applied for a building permit under the Building Code Act, S.O. 1992, c. 23, as amended, and has undertaken a repair to the existing Class 4 septic system at 1376 River Road, Manotic, Ontario. 2. Description of Construction The Applicant is under contract to institute repairs to the septic system serving an existing Class C, residential building having a total finished area of 260 m 2. The dwelling contains a total of 22.5 fixture units and is serviced by the existing class 4 septic system having a total daily design flow rate of 2200 litres/day. The site is grass covered and has a northerly slope of approximately 13%. There is a drilled well on site to supply water to the residential dwelling. The subject septic system is identified as a Class IV F.M. (filter media) type leaching bed, 28 m 2 in contact area. It was approved by the Ministry of Environment and Energy (MOEE) and constructed in The original system was failing and a permit for the repair of the system was sought to rectify the situation. Upon investigation of the malfunctioning system by the Applicant it was discovered that the leaching bed did not have a sand mantle which was to have been provided under MOEE guidelines at the time of initial construction. In addition, it was apparent that filter media sand had not been used in the construction of the leaching bed. Further, the bed had been backfilled and covered with low permeability silty clay material. The pipe between the septic tank and leaching bed was cracked and sloping in the wrong direction and the upper 0.3 m of the sand filter material below the distribution pipes was plugged with organic material (biomat) which was preventing the dispersion of effluent. As part of the repair of the malfunctioning system the biomat impacted sand filter material beneath the leaching bed was removed and replaced with crushed stone. The distribution pipes were also replaced and an additional two runs of pipe to the leaching bed were added, increasing the loading area from 28 m 2 to 42 m 2. Further, the silty clay material was removed from the sides and top of the leaching bed and the 15 metre long, 0.5 m thick sand mantle extending the full width of the bed, which should have been provided with the initial construction, was added. The specific element of the repair in dispute involves the sand filter material used in the repair of the leaching bed. An initial grain size evaluation of the sand filter material, informed that the gradation of the subject material was slightly outside the OBC envelope for filter media sand. The permit which as issued in connection with the repair specified that Filter Media sand was required if the bed was to be rebuilt, as such, the Respondent is of the opinion that the material used in the leaching bed repair does not comply with Code requirements. The Applicant s position in this regard is that the permeability of the subject sand material is at least equal to or exceeds that of the sand filter material used in the original construction. In this regard, as determined by additional testing of the material at the request of the Commission, it was found that the coefficient of uniformity of the original sand filter material was 10.7, while the sample taken from the new material in dispute had a uniformity coefficient of 12. Further, it was determined that the grain size curve for the new material more closely reflected the gradation envelope depicted in the Code.

3 -3-3. Dispute The issue at dispute between the Applicant and Respondent is whether the grain-size of the sand filter material used in the repair of the existing septic system provides sufficiency of compliance with Sentence (1) of the Ontario Building Code (OBC). This sentence of the Code provides that, when an existing building system is materially altered or repaired, the performance level of the building shall be at least equal to the performance level prior to the alteration or repair. In this regard, the grain-size analysis performed on samples of both the original and newly added material would appear to illustrate a slight improvement in quality. In other words, while not meeting the requirement for filter media material as outlined in the permit approval in relation to the repair work being undertaken, the grain size curve of the new material more closely conforms to the OBC gradation envelope than does the original sand. 4. Provisions of the Ontario Building Code Material Alteration or Repair of a Building System (1) Where an existing building system is materially altered or repaired, the performance level of the building after the material alteration or repair shall be at least equal to the performance level of the building prior to the material alteration or repair. 5. Applicant s Position The Agent for the Applicant outlined the condition of the existing failed system upon initial inspection. He advised that the leaching bed was surrounded by clay on all four sides and effluent was being discharged to the surface. In an effort to improve the situation, the clay material was removed from three sides of the bed and new sand filter material was laid. Furthermore, although the Ministry of the Environment issued a Use Permit in August 1988, the required mantle for the system was not provided. They have now constructed this mantle in accordance with the original permit. The Agent argued that all of the repair work undertaken constitutes an improvement to the existing situation and, therefore, complies with the Part 11 requirements of the Code. The Agent acknowledged that the permit issued by the Ottawa Septic System Office in connection with the subject repair specified that filter media sand was to be used if the bed needed to be rebuilt. He also acknowledged that there are exacting specifications for filter media sand, in light of the potential for substandard material to contribute to the clogging of the bed. Despite this, the Agent advised that the contractor had obtained sand filter material that did not meet the standards for new construction set out in the Code. He admitted that the subject material was preferred by the installer because it was less expensive than filter media sand. Despite this however, the Agent emphasized that the material which has been used is equal or superior to the original sand filter material employed in the subject system. At the request for testing by the Commission, the Agent submitted results which indicated that the coefficient of uniformity of the original sand filter material was found to be 10.7 while the sample taken from the new material in dispute had a uniformity coefficient of 12. The results further illustrated that the grain size curve for the new material more closely conformed to the OBC gradation envelope than the curve depicted for the original sand. This, the Agent argued, represents an improvement in the quality of material used in the filter bed and therefore provides sufficiency of compliance with the Part 11 requirements of the Code.

4 -4- In summation, the Agent stated that, when considering Article , the repair which was undertaken does not reduce the performance level of the system. The tests conducted prove that the filter sand used to replace the existing material is better than what had been approved for use by MOEE at the time of original construction. He emphasized that this is a repair situation and should not be held to the same standards as new construction. 6. Respondent s Position As background to the subject dispute the Respondent advised that the sewage system was approved by the Ministry of Environment as a filter bed in May The sand supplier, Greely Sand and Gravel Inc., for the 1988 bed provided weigh bills for filter media for the sand fill for the bed. The contractor Eric Draper certified that sand filter material was used. The Ministry of the Environment issued a Use Permit (August 8, 1988) for the system, despite the absence of a mantle, backfilling and grading. No mantle was installed. The Respondent submitted that, in response to the Applicant s request, a sewage permit was issued by the Septic System Office for the repair of the tile bed on the subject property. Further, it was specified on the permit that if the bed was to be replaced, filter media sand was to be used. In this regard, by way of a letter from the Agent for the Applicant dated May 2, 2002 it was acknowledged that (t)he grain size distribution of the filter sand is also known to be a factor contributing to the clogging of the filter sand. For this reason, there are strict specifications for filter madia sand material. Agreeing with this analysis the Respondent advised that receipts/waybills are required to be provided by permit applicants to prove that the grain size of the filter media sand would meet Code requirements. No such receipts were supplied in connection with this case, however it appeared evident upon inspection that the grain size of the new material used would not meet Code specified standards. Furthermore, the Respondent stated that the work that has been undertaken on the subject site constitutes more of a replacement than a repair. He was uncertain exactly how much sand had been used and believed that the entire bed had been replaced and expanded. In any event, he was not satisfied that the material that had been used was at all satisfactory. He also argued that the Agent s claim that the system had been improved was not entirely valid. He stated that any repair made to a failed system will result in some improvement in performance but this does not mean that all changes will result in a viable sewage system. The standard which must be met is whether it constitutes an improvement to what the system was originally designed and constructed to achieve. The benchmark of Part 11 is not the failed system but the old, original, system. The Respondent submitted that, in his opinion, filter media sand was required in the construction of the original system and, therefore, filter media sand must be used in the repair. In respect to the results of the testing done at the Commission s request, the Respondent admitted that the new material tested marginally better than the original sand but stated that neither is acceptable, and both have coefficient uniformities greatly beyond OBC requirements. The Respondent also provided the Commission with a report of what has occurred on the property between the initial hearing of this matter and the reconvened session. He submitted that, in contravention of acceptable standards of practice, the installer had proceeded to backfill the site without inspection and has sodded the area. Moreover, the Respondent argued that, because of the new runs of distribution pipe added, this repair also contained an element of new construction that is required to comply with the minimum standards of the Code. In summation, the Respondent reiterated that the permit which had been issued specified the use of filter media sand. Cost, he argued, should not be an acceptable reason for not complying with the Code. He is concerned that the system, as now constructed without the benefit of inspection, will fail again.

5 -5- He submitted that as little as three inches of biomat material would cause a system to fail and with the use of this substandard material in the bed, he felt that failure would likely occur. 7. Commission Ruling It is the decision of the Building Code Commission that, in the matter of the grain-size quality of the imported sand fill used to repair the existing leaching bed, the sand fill provides sufficiency of compliance with Sentence (1) of the Ontario Building Code at 1376 River Road, Manotic, Ontario. 8. Reasons i) Based on the construction details provided by Morey Houle Chevrier Engineering Ltd. and the single grain-size analysis for the existing sand fill, the existing bed, although approved in 1988 as a filter bed (now defined in Section ), and provided with a Use Permit on August 8, 1988, was not constructed to the prevailing standards. ii) iii) iv) The sand fill used in the repair, based on the two grain-size analyses provided is, on average, superior in quality to the existing sand fill. Although the Building Permit and the Engineer s specifications both required filter sand (as defined by Sentence (3)), no Order was issued relative to the system and, therefore, Part 11 of the Code applies to the repair that has been undertaken through a permit. In viewing the repair, it is considered that the quality of the new sand fill provided will not result in a loss of performance when compared to the existing sand fill, prior to the plugging of the sand by biomat. 9. Comments/Recommendation Although not considered in this Decision, it is recognized that the provision of the mantle (not considered a compensating measure because it was required in the original approval) and the extra runs of pipe and accompanying stone should improve the performance of the system. However, it should be noted that the substandard filter sand material may result in a future failure because of plugging and biomat formation. In addition, the system expansion by the provision of extra runs of distribution pipe supplied does not meet the requirements of Sentence (1), in that the sand fill used in this new construction does not meet the requirements of Sentence (3) of the Ontario Building Code. In view of the discrepancy between Part 11 and the requirement of the Septic System Permit (and design specifications) outlined in Part 8 and issued for this repair, it is recommended that the Building and Development Branch of the Ministry of Municipal Affairs and Housing consider an amendment to the Ontario Building Code which would require that any construction undertaken under Part 11 must, at a minimum, conform to the requirements outlined in the Building Permit which was issued for the original construction.

6 -6- Dated at Toronto this 8 th day in the month of August in the year 2002 for application number Bryan Whitehead, Chair