Green Roof Wind & Fire Design Guidelines: After Three Years, Half the Battle is Won

Transcription

1 The Green Roof Guy Green Roof Wind & Fire Design Guidelines: After Three Years, Half the Battle is Won By Kelly Luckett, LEED AP, GRP, The Green Roof Guy Photos Courtesy Kelly Luckett Unless Otherwise Noted December 22, 2009 Southern Illinois University Edwardsville (SIUE) Wind Tunnel Testing in June, Hello once again Green Roof Fans, As many of you know, the Green Roof Guy has been waste deep in the efforts to get design guidelines for minimizing risks of fire and wind uplift for green roof systems inserted into the International Building Code. The journey that started nearly three years ago has been one with many starts and stops and has been a continuous learning process. You may recall the initial discussions throughout the industry as to whether testing was necessary or even possible. The decision was made to develop design guidelines that would govern how we build green roofs rather than attempting to test seemingly infinite green roof variations.

2 However, as we coursed down this winding road, the wind design guide called Single Ply Roofing Industry (SPRI) / Green Roofs for Healthy Cities RP-14 met with some resistance that we could not overcome without conducting some testing. Though the testing we conducted in the wind tunnel at Southern Illinois University Edwardsville this past summer may not be sufficient to gain the endorsement of everyone in the canvass pool, the tests were very enlightening and clearly revealed some issues regarding the minimum level of vegetative coverage necessary to keep the growth media from becoming airborne. The testing report is nearing completion and once it has been approved for release, I will dedicate an entire column to more fully explain everything we evaluated and exactly what we learned. For now, what I can share with you is that RP-14 is being edited to reflect what we learned through the wind tunnel testing and will be sent out for the fourth round of balloting to the canvass pool soon. Testing at SIUE to help develop prescriptive design guides for wind uplift (RP-14) for green roof design and construction. The fire standard called SPRI / Green Roof for Healthy Cities VF-1 received the necessary approval from the majority of the canvass pool and has been submitted to American National Standards Institute (ANSI)

3 for approval as a consensus based standard. We had hoped to have the ANSI approval in hand for the International Code Council (ICC) hearings held in Baltimore in November, When that didn t happen, our strategy for the hearings was to introduce the standard anyway in hopes of gaining acceptance based on the expectation that ANSI approval would be attained before the printing of the updated building code. In addition to proposing the insertion of VF-1 into the fire safety section of the building code, we also felt that that section of VF-1 that deals with maintenance of green roofs needed to be inserted into the property maintenance. This would pull the maintenance of green roof systems into the same category as the rest of the building envelope and effectively making it the property owner s responsibility to maintain their green roof and gives the local building inspector authority to issue citations for noncompliance. Does your head hurt yet? Wait, it gets better. The proposal before the property maintenance committee was the first of our proposals to be heard. Though I felt this was going to be a pretty easy sell to the committee, as I stepped to the microphone I noticed the line forming to oppose the measure. While I ve learned to expect the unexpected at ICC hearings, I was surprised not by the opposition, but from where it was coming. Code enforcement officials testified before the committee that they conduct exterior inspections, in many cases from the street. Additionally, they felt their inspectors were not qualified to inspect green roof plants and were less than enthusiastic about getting them qualified. As the committee makeup was primarily public works employees from various cities around the country, testimony from fellow public works department employees easily swayed the vote; 10-0 disapproval of our proposal. As many of you know, green roof maintenance has been an issue that has been troubling me for some time and as you can imagine I was more than disappointed. I saw this as a missed opportunity for the green roof industry. I invited a friend to engage in a high level strategic planning session at the hotel bar or at least join me in a cocktail while I vented some of the steam from my collar. My friend is far more engaged in the ICC proceedings than I and he informed me that a couple of code change proposals were approved by the fire code committee a week earlier that could effectively accomplish the same thing. Turns out he was right, the fire code committee approved a proposal that says: SECTION 318 VEGETATION ON ROOFS Maintenance of vegetation. Vegetation placed upon buildings shall be maintained to prevent the accumulation of weeds, grass, vines, trees, or other growth that is capable of being ignited. All vegetation that poses a fire hazard to the building or exposure structures shall be removed from the building Maintenance plan. The fire code official is authorized to require a maintenance plan for vegetation placed on roofs due to the size of a roof garden, materials used, or when a fire hazard may exist to the building or exposures due to the lack of maintenance. What is significant here is that our proposal attempted to place the responsibility for policing green roof maintenance with the building inspector. The building inspector typically only gains access to the property when there has been an application for an occupancy permit and his inspection is postconstruction. The proposed code change approved by the fire code committee shifts the policing of green roof maintenance to the fire marshal who conducts routine inspections throughout the occupancy of the building, and allowing the fire marshal to require a maintenance plan moves the review of the green roof maintenance to plan review; which takes place prior to the issuance of the building permit. This moves the conversation that green roof providers must have with property owners about green roof maintenance to the forefront of construction design instead of being an afterthought that only comes up when problems arise.

4 Left: A highly maintained greenroof, Photo Courtesy ZinCo; Right: A not-so maintained greenroof, Photo Courtesy and By Janet Faust. But wait, there s more. The fire code committee also approved a measure that contained the core action items from VF-1. The following language was approved for inclusion in the next printing of the International Building Code: SECTION ROOF GARDENS AND LANDSCAPED ROOFS General. Rooftop gardens and landscaped roofs shall be installed and maintained in accordance with this code and Sections and of the International Building Code Rooftop garden or landscaped roof size. Rooftop garden or landscaped roof areas shall not exceed 15,625 ft2 (1,450 m2) in size for any single area with a maximum dimension of 125 ft (39 m) in length or width. A minimum 6 ft (1.8m) wide clearance consisting of a Class A (per ASTM E108 or UL790) rated roof system shall be provided between adjacent rooftop garden or landscaped roof areas Rooftop structure and equipment clearance. For all vegetated roofing systems abutting combustible vertical surfaces, a Class A (per ASTM E108 or UL790) rated roof system shall be achieved for a minimum 6 ft (1.8 m) wide continuous border placed around rooftop structures and all rooftop equipment, including but not limited to mechanical and machine rooms, penthouses, skylights, roof vents, solar panels, antenna supports, and building service equipment Vegetation. Vegetation shall be maintained as described in Sections and Irrigation. Supplemental irrigation shall be provided as necessary to maintain levels of hydration necessary to keep green roof plants alive and to keep dry foliage to a minimum Dead foliage. Excess biomass such as overgrown vegetation, leafs and other dead and decaying material shall be removed at regular intervals not less than two times per year (IBC [F] ) Roof gardens and landscaped roofs. Buildings or structures with roof gardens or landscaped roofs that are equipped with a standpipe shall extend the standpipe to the roof level on which the roof garden or landscaped roof is located. Let me remind you that all this happened before our scheduled time slot at the code hearings to introduce VF-1, which has not yet garnered ANSI approval. While having this language in the fire code section of the building code is great, it needs to also be in the fire safety section of the building code, which is where we our proposal was to be presented. Coincidentally, the gentleman who sponsored the code change proposal that the Fire Code Committee approved had a proposed code change on the

5 schedule immediately before the VF-1 proposed code change. After some code hearing wrangling, the gentleman agreed to modify his proposal to simply read as a pointer from the fire safety section of the building code to the fire code section of the building code, instructing code enforcement officials enforcing the building code requirements for green roofs to reference the language in the fire code. When the committee approved the pointer proposal, some of the urgency to propose VF-1 was relieved. Rather than to introduce VF-1 now, without ANSI approval in hand, and be subjected to opposing testimony, we decided to request the committee to disapprove the proposal; which automatically keeps a placeholder at the committee action hearings next spring. By then we will have ANSI approval in hand and can testify that the core action items have been accepted by ICC committees and that acceptance of VF-1 at that time, only brings the building code into alignment with what the other committees have already approved. Kelly Luckett Well, green roof fans, that s almost half the fire and wind uplift battle. Wind uplift issues and RP-14 still remain. RP-14 goes out for the fourth round of balloting in the next few weeks. I will keep you posted as the standard evolves. As the holiday season settles in and we turn our focus toward issues a little closer to home, I d like to wish you and your family a wonderful holiday season. Between bail outs and reforms, incitements and accomplishment, I am confident that the dream is still alive. We will, once again, unleash that special quality that makes us American and sees us through to a brighter tomorrow.