A long-term, problem-free commercial flat roof solar installation starts with knowing about the roof systems themselves and how to keep them protected. This isn’t easy. For one, there is an alphabet soup of acronyms: PVC, TPO, EPDM, SBS, APP, BUR, PUF, PIB, CSPE, EPS and XPS. The roof industry lingo doesn’t seem to make much sense either, such as the difference between mechanically attached (MA) and fully adhered (FA), even though both are essentially screwed down mechanically.In order to mitigate roof damage during construction, there are a few things we need to know. PVC, TPO, EPDM, PIB and CPSE are all single ply membranes, typically between 3/32 and 1/8-in.
/. Advertisement./In general, roof protection falls into two categories:. Temporary protection is the roof safeguard deployed during construction to avoid damaging the roof and is subsequently removed upon completion of construction. Some of these protections are universal among roof types and some are membrane specific. Permanent protection will include slip sheets, separator sheets, walk pads and walkways. These items stay on the roof for the life of the PV system.Guidelines for temporary protectionInspect the roof prior to starting work. Ensure there is no damage to the roofing membrane, including punctures and scratches to the surface.
New Flat Roof with Tapered Insulation August 5, 2010 by Thomas Petrilli This is an EPDM (rubber) roof; it was installed over an existing built up (tar and gravel) roof; due to a number of factors it consistently held about 4″ of water on its surface.
Any such damage should be circled and reported immediately so that it may be repaired quickly. Panels must not be placed over damaged areas until the damage is repaired.Treads on wheeled equipment should be covered or other precautions taken to ensure that gravel embedded in the treads does not create a membrane puncture hazard. Motorized equipment should be limited to those that can start and stop gradually to minimize horizontal pulls on the membrane.Avoid damage to the foam board insulation layer below the membrane by:. Place all pallet loads on foam board sheets or similar materials that can spread the load without damaging the membrane or insulation below.
Protect areas that are frequently traveled with plywood or OSB boards (weighted down whenever necessary to prevent uplift by wind). Also, wherever possible, frequently change the travel path location.Avoid separation of the membrane from the insulation by placing a layer of spaghetti matting (or similar approved matting material) on areas that will be rolled over more than two or three times. Any damage to the roof must be identified with a clear mark on the roof immediately after it occurs, and it should be promptly reported to the construction manager.
Place all pallet loads on foam board sheets or similar materials that can spread the load without damaging the membrane or insulation below. Protection proceduresFor hoist landing areas and rooftop storage of any material in excess of 15 lbs/sf, use a rigid temporary protection system consisting of sheets of plywood or OSB, applied unadhered on the roof. Fully cover scheduled work areas with loosely abutting plywood sections, and apply dunnage insulation pieces between plywood sections and the roof membrane for heavy access or traffic conditions.
Protect the plywood sections from wind displacement. Remove temporary rigid protection promptly upon completion of hoisting, loading or heavy traffic work.When constructing ramps and work platforms, protect the roofing by arranging pieces of dunnage insulation between the ramp leading edges and all ramp/platform sleeper and support contact points.Utilize temporary flexible protection consisting of rolls of walk mat material at all traffic lanes, which are essentially any areas subject to repeat or routine movement of personnel or carted materials. Loose walk mat material should be picked up and secured at the end of each day or whenever inclement or windy weather is predicted.Ensure that the wheel load for rolling equipment does not exceed 15 psi. For example, wheeled equipment capable of carrying 1,200 lbs (combined self weight plus load) should have at least 80 sq in.
Of wheel contact area. If the equipment distributes the load on four wheels evenly, each wheel should have at least 20 sq in. Of contact area. If the contact width is 4 in., the contact length must be at least 5 in. If the area is insufficient, either the load must be reduced or additional wheels must be added.