A seamless sheet installation system preferably includes a seamless sheet and a plurality of sheet retention devices. The seamless sheet is retained on a tube. A pair of rotating retention devices may be inserted into ends of the roll. Each rolling retention device includes a tube plug and a rotating handle. An end of the seamless sheet is secured to the top eave flange. The seamless sheet is held against a bottom of the eave purlin web with one of the plurality of sheet retention devices. The sheet retention device may have any suitable design. The seamless sheet is rolled out to successive purlins, wrapped over the top flange and anchored to a bottom of the vertical web with one of the plurality of sheet retention devices. The seamless sheet wrapping process is terminated at an opposing eave purlin or a ridge purlin. Insulation is then inserted between adjacent purlins.

An induction heating tool that holds voltage or current supplied to the induction tank circuit constant and tracks changes in the other of voltage or current during each induction heating cycle. The disclosed induction heating tool exploits the fact that the resistance an attachment plate increases along with the temperature of the attachment plate. During an induction heating cycle, the attachment plate is magnetically coupled to a work coil and the resistance of the attachment plate is reflected to the circuit. Changes in the resistance of the attachment plate alter the pattern of energy delivery from the work coil to the attachment plate in a predictable way. Calculations accurately predict the temperature of the attachment plate over a wide variety of ambient conditions, including the presence of moisture at the membrane/attachment plate interface. The disclosed induction heating tool produces consistent results without calibration for ambient conditions.

A foam roofing underlayment is provided with a reinforcement membrane having an array of fastener elements for engaging fastener elements on a flexible roof membrane. The underlayment is formed by molding foam between the reinforcement membrane and a carrier membrane. The underlayment in secured to the roof using washers having fastener elements for engaging the fastener elements of the flexible roof membrane. An anti-peel flap with fastener elements is provided around the periphery of the washers. A slip sheet is used between the underlayment and the flexible roof membrane to permit accurate positioning of the flexible roof membrane prior to engagement of the fastener elements. The interstices between the fastener elements provide lateral moisture paths to vents in the flexible roof membrane.

A foam roofing underlayment is provided with a reinforcement membrane having an array of fastener elements for engaging fastener elements on a flexible roof membrane. The underlayment is formed by molding foam between the reinforcement membrane and a carrier membrane. The underlayment in secured to the roof using washers having fastener elements for engaging the fastener elements of the flexible roof membrane. An anti-peel flap with fastener elements is provided around the periphery of the washers. A slip sheet is used between the underlayment and the flexible roof membrane to permit accurate positioning of the flexible roof membrane prior to engagement of the fastener elements. The interstices between the fastener elements provide lateral moisture paths to vents in the flexible roof membrane.

An induction heating tool that holds voltage or current supplied to the induction tank circuit constant and tracks changes in the other of voltage or current during each induction heating cycle. The disclosed induction heating tool exploits the fact that the resistance an attachment plate increases along with the temperature of the attachment plate. During an induction heating cycle, the attachment plate is magnetically coupled to a work coil and the resistance of the attachment plate is reflected to the circuit. Changes in the resistance of the attachment plate alter the pattern of energy delivery from the work coil to the attachment plate in a predictable way. Calculations accurately predict the temperature of the attachment plate over a wide variety of ambient conditions, including the presence of moisture at the membrane/attachment plate interface. The disclosed induction heating tool produces consistent results without calibration for ambient conditions.

A method of securing a thermoplastic roofing membrane onto a roofing assembly, by: (a) providing a roofing component positioned at the top of a roofing assembly, wherein the roofing component has a thermoplastic top surface; (b) placing a thermoplastic roofing membrane over the top of the roofing component; and then (c) heating the thermoplastic roofing membrane together with the top surface of the roofing component to cause the thermoplastic roofing membrane to fuse to the top surface of the roofing component.