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 with Article of the Regulation 350/06, as amended, the Building Code. AND IN THE MATTER OF an application by Paul Mior, Abbotsford Group Inc., for the resolution of a dispute with Ann Borooah, Chief Building Official, City of Toronto, to determine whether the proposal to install an un-vented roof assembly, using 2 lb. medium density polyurethane spray foam to insulate the roof, provides sufficiency of compliance with Article of the Building Code at 39 Alma Drive, Toronto, Ontario. APPLICANT RESPONDENT PANEL Paul Mior Abbotsford Group Inc. Toronto, ON Ann Borooah Chief Building Official City of Toronto Prabhakar Mahant, Vice Chair Mina Tesseris Doug Clancey PLACE Toronto, Ontario DATE OF HEARING October 22, 2009 DATE OF RULING October 22, 2009 APPEARANCES Paul Mior Abbotsford Group Inc. Toronto, ON The Applicant Al Jasinevicius Chief Building Official City of Toronto The Respondent

2 -2- RULING 1. Particulars of Dispute The Applicant has received an Order to Comply under the Building Code Act, 1992, to remedy certain alleged code contraventions at 39 Alma Drive, Toronto, Ontario. The subject building is an existing two storey, residential dwelling, comprised of combustible construction with a new third storey addition. The construction in dispute is with respect to the installation of 2lb medium density closedcell polyurethane spray foam insulation in the void space between the roof joists and roof sheathing of the new third storey addition, which contains both flat and sloped portions. Except where it can be shown to be unnecessary, Sentence (1) of the Code requires a space to be provided between the insulation and the sheathing, where insulation is installed between a ceiling and the underside of the roof sheathing and requires vents to be installed to permit the movement of air from the space to the exterior. In this case, no air space has been provided between the roof sheathing and the insulation and no vents have been installed. The Applicant is of the position that the spray foam insulation proves that venting in this case, is unnecessary and therefore, sufficiently complies with Article of the Code. The Respondent s position is that adequate roof ventilation must be provided for the spaces between the roof sheathing and the proposed insulation in accordance with Sentence (1) of the Code. 2. Provisions of the Building Code in Dispute Required Venting (1) Except where it can be shown to be unnecessary, where insulation is installed between a ceiling and the underside of the roof sheathing, a space shall be provided between the insulation and the sheathing, and vents shall be installed to permit the movement of air from the space to the exterior. 3. Applicant s Position The Applicant submitted that the subject building is a single family residence that is being renovated and a new third storey has been added to the building. The third storey roof structure consists of both flat and sloped portions framed with cm deep wood joists. The Applicant advised that although the original permit drawings called for mineral wool batt type insulation to provide the necessary thermal resistance rating and venting above the insulation, the owners had since decided to install 2lb medium density closed-cell polyurethane spray foam to insulate the roof instead. The Applicant submitted that Morrison Hershfield Ltd, and independent consulting engineering firm, was retained to conduct a review of the installed closed-cell, mediumdensity, spray applied polyurethane foam insulation. The Applicant stated that Morrison Hershfield s report concluded that due to the unique nature of the polyurethane spray foam used in this application, venting is not required. The report indicated that since there are no gaps or empty spaces between the insulation and the

3 -3- underside of the roof sheathing, venting has been shown to be unnecessary in this case. Further, Morrison Hershfield s onsite observations included that polyethylene sheeting and gypsum sheathing had been installed to act as the vapour and air barriers. The Applicant advised that Morrison Hershfield s report indicated that daily test reports were conducted in accordance with Section of CAN/ULC-S , confirming test results for density, cohesion and adhesion surpassed the requirements of the Standard. The Applicant argued that Morrison Hershfield s report states that the practice of insulating the underside of the roof sheathing with polyurethane spray foam insulation without venting is widely and successfully practiced across Canada because the spray foam insulation performance provides the required resistance to vapour diffusion and air leakage where the venting requirement per Article (1) is shown to be unnecessary. The Applicant submitted Morrison Hershfield s opinion that the expanding and bonding nature of the product, the requirements by the manufacturers for skilled installers and the assurance that the material was installed as intended, the spray foam insulation will provide the level of performance required by the Code. Further, the Agent advised that in addition to Morrison Hershfield, an opinion from another independent engineering consulting firm had also been retained. The Applicant informed the Commission that Buchan, Lawton, Parent Ltd., reported the same findings as Morrison Hershfield and that it was their opinion that the installation of the polyurethane spray foam insulation and vapour barrier had been installed in accordance with the manufacturer s specification and the CAN/ULCS705.2 Standard and further, the installation was in conformance with the requirements of the Building Code. The Applicant also presented a Branch Opinion dated May 1997 regarding Section of the Ontario Building Code, issued by the Ministry of Municipal Affairs and Housing, which stated, It is the opinion of the Housing Development & Buildings Branch that, where a roof assembly is filled with rigid insulation (no gaps or empty spaces in between), Subsection 9.19 of the OBC need not apply. In response to questions, the Applicant maintained that airtight and insulated pot lights would be used in the flat portions of the roof installed with the appropriate clearance distance from the insulation. In conclusion, the Applicant maintained that in light of two independent engineering consultant s opinions, the subject foam spray installation would provide a continuous air and vapour barrier and further, provides sufficiency of compliance with Sentence (1) of the Building Code, as venting has been shown to be unnecessary in this circumstance. 4. Respondent s Position The Respondent stated that he was concerned with the products performance in this type of application. The Respondent submitted that the subject product identified as BASF walltite has been evaluated by the Canadian Construction Materials Centre (Evaluation Report No R) and had an approval for installation in open wall cavities only, not in ceiling spaces such as cathedral ceilings, as is in this case. The Respondent maintained that there was lack of technical information on the application and performance of this spray foam on roof assemblies. The Respondent also stated that the subject ceilings will contain pot light penetrations; and

4 -4- as such, the penetrations if not sealed properly could be a source of moisture penetration. Further, the Respondent submitted that as a result of the lack of ventilation, the building materials within the roof assembly (i.e. roof sheathing, roof shingles, and roof rafters) may not perform as intended and as a result, warranties may be voided. The Respondent stated that it was his opinion that adequate roof ventilation must be provided in the space between the roof sheathing and the proposed insulation to satisfy the roof ventilation requirement set out in Sentence (1) of the Building Code. 5. Commission Ruling It is the Decision of the Building Code Commission that the proposal to install an un-vented roof assembly, using 2 lb. medium density polyurethane spray foam to insulate the roof provides sufficiency of compliance with Article of the Building Code at 39 Alma Drive, Toronto, Ontario. 6. Reasons i) Sentence (1) of the Building Code states, Except where it can be shown to be unnecessary, where insulation is installed between a ceiling and the underside of the roof sheathing, a space shall be provided between the insulation and the sheathing, and vents shall be installed to permit the movement of air from the space to the exterior. ii) iii) iv) It is the Commission s opinion, based on the evidence and testimony presented, that the installation of the 2 lb. medium density polyurethane spray foam to insulate the roof provides an air seal that will minimize air leakage and reduce the potential for condensation. Therefore, venting in the subject roof assembly has been shown to be unnecessary. Sentence of Division B of the Building Code requires that spray-applied polyurethane insulation be installed in accordance with CAN/ULC-S The Commission heard that the closed-cell spray polyurethane foam has been installed and tested in accordance with CAN/ULC-S Standard for thermal insulation as referenced by the Code. The Commission was advised that a vapour barrier has been provided, as per Subsection of the Building Code. The Commission was advised that the pot lights that have been used are sealed units with a vapour barrier around them and are ULC listed. v) Considering the design of this roof and the climatic data for Toronto contained in Supplementary Standard SB-1 of the Ontario Building Code, it is the Commission s opinion that the potential for ice damming is minimal

5 -5- Dated at Toronto this 22 nd day in the month of October in the year 2009 for application number Prabhakar Mahant, Chair Designate Mina Tesseris Doug Clancey