METHOD OF APPLICATION First Layer of Bauder Bakor 790- 11 The application of the Bauder Bakor 790- 11 system to the main deck area is carried out in a planned and organised manner to achieve an even monolithic application of the system across the deck. The hot melt membrane is applied in two 3 mm thick layers at the combined nominal rate of 6.5kg/ m ² for the two layers. The system is installed using a grid method to accurately control the consistent application rate of the membrane across the whole area of the deck. Working methodically within a 900 mm wide grid line, the first 3 mm layer of membrane is installed by pouring the Bauder Bakor 790- 11 hot melt onto the deck and spreading it with a rubber bladed squeegee, to achieve an even coverage over the whole width area within each grid line. Reinforcement Sheet When the first section of hot melt membrane has been spread and is still hot, the relevant reinforcement layer, usually the Bauder Polyester Fleece is carefully placed into the first layer of hot melt, and rolled out, fully bedding the fleece into the hot melt membrane. A wide headed clean brush can be used to brush down the fleece into the hot melt to ensure it is fully bedded into the membrane with no air pockets and no bare areas of deck beneath. The fleece, which is white in colour, will turn grey as the bitumen starts to partially bleed through. The installer only lays enough of this first layer that can be safely covered by the second coating layer and its relevant access/ protection layer by the end of each day or according to the prevailing weather conditions. Second Layer of Bauder Bakor 790- 11 The second layer of membrane is always installed on the same day as the first and is applied in the same manner; pouring, and evenly spreading the membrane to a 3 mm depth within each ' grid line' formed by the polyester reinforcement. As the installation of the second layer progresses, the appropriate Access/ Protection sheet is bedded into the membrane while it is still hot. Typically, hot melt monolithic rubberised bitumen systems are installed, by first waterproofing the details of the deck such as upstands and outlets, before applying the membrane to the main field area of the deck. Standard method of detailing using Hot Melt The Bauder Bakor 790- 11 is first poured carefully into the nick of the upstand, and then drawn up the upstand in a series of passes with the trowel or plywood spreader. With each pass, the membrane is built up to 3 mm in thickness. The relevant reinforcement is then bedded into the membrane whilst it is still hot. Where the upstand is monolithic concrete, block or brickwork, the reinforcement will be polyester fleece. Where the upstand is formed in metal, timber, plywood or any other material, the reinforcement will be part- cured neoprene. The second 3 mm layer of membrane is then applied using the same method as previously described. The specified Bauder access/ protection sheet is then fully bedded into membrane while it is still hot. Waterproofing to items of complex detailing The application of the waterproofing system to these details will vary depending on a number of factors, including the construction sequencing, design of the protrusion such as a balustrade base, size & shape etc. Other considerations include surface levels, expansion joint widths, and initial construction movement or anticipated post- installation movement. CAD drawings for standard detailing are available for download on our website, www. bauder. co. uk/ technical- centre Additionally we can advise, design, and provide CAD drawings to illustrate the waterproofing detailing to any structure on receipt of drawings, for guidance. Complex detailing may include: n Balustrades n Vent pipes n Expansion joints n " I" beams n Metal upstand brackets n Concrete stairways n Smoke vents n Glazing cills An example of now a very complex detail features can be undertaken using the Bakor 790- 11 waterproofing. 78 bauder. ie

TESTING AND INSPECTIONS As part of their own quality control procedures, the installing Bauder Approved Contractor will mechanically test the membrane as it is installed to ensure that the membrane is at least 6mm thick beneath the protection sheet. Additionally, our site technicians will randomly inspect the work during installation. To meet the criteria of the Bauder System Guarantee, we will carry out the final inspection with the Approved Contractor in attendance to ensure the integrity of the finished roof and that it meets the required standards of installation. Any issues identified will be reported to the Bauder Approved Contractor for immediate rectification. Any remedial work will then be re- tested. As the Bauder Bakor 790- 11 monolithic membrane system is described as a ' Protected Roof Membrane' it should always be covered by some form of build up. This will generally entail following trades accessing the roof and using it as a platform to install the additional finish. Bauder recommends that integrity testing be carried out and the results notified to the client and Bauder prior to any other trades works starting. There are a variety of testing options available: Leak Testing Immediately prior to installing any landscaping, the integrity of the waterproofing system must be independently checked for leaks. The method of testing should be agreed with the client's representative. Electronic Test This method is considered the quickest and most accurate method of testing, as this accurately locates very small penetrations on main deck areas. Independent certification is a warranty requirement and a copy of this test certificate must be submitted to Bauder Ltd prior to the issue of the Guarantee. Additional Localised Testing It has been known that the electronic method can be inaccurate when conducted in close proximity to metal objects, such as outlets, & metal upstands. In these cases a localised flood test against the areas/ details to be checked is more accurate and may be done in conjunction with the electronic test method. Once all additional trades have completed their works, it may be necessary to re- test any affected areas and remedial repairs made. EQUIPMENT The Bakor 790- 11 material must first be heated to the correct temperature until it is molten, during which time it is constantly mixed to ensure its full physical properties develop. The rubber content of the membrane, which is integral to this form of waterproofing material, makes it necessary to use indirect heat, as achieved by using a double- jacketed hot melt mixing machine ( unlike a standard single- shell asphalt mixer). The outer jacket holds a heat transfer oil that when heated by one or two propane burners, gently warms the Bauder Bakor 790- 11 compound in the inner jacket. This type of mixer ensures uniform heating of the material. Air jacketed machines are also a popular alternative, which can offer additional benefits of economy and versatility. A mechanical sweep agitator within the machine keeps the melted compound stirred. This is usually at the bottom of the inner shell and takes the form of a reciprocating blade, driven via external cranks and powered by a small engine mounted on the machines chassis. The oil- jacketed melting machine is typically equipped with two temperature gauges, so that the mixer operator can continually monitor both the temperature of the heat transfer oil and the 790- 11 compound. The safe operating temperature ranges from 162° C to 215° C ( 320° F to 419° F) with the most common operating temperature range from 180° C to 200° C ( 356° F to 392° F). ACCESS AND PROTECTION LAYERS For all applications, whether it is roofing or tanking, the membrane requires an access/ protection layer bedded into it to protect it from trafficking and likely damage from following trades. The protection layer also allows for access for the safe installation of the landscape finish. The type of protection layer will depend on the proposed build- up and the expected period of time that the system is going to be exposed to following trades. Bauder AP1 This is a 2.2 mm reinforced modified bitumen membrane for use on horizontal and vertical surfaces to provide access and solar protection. Bauder AP2 A 4 mm reinforced modified mineral surfaced bitumen membrane root barrier for horizontal and vertical surfaces, and solar protection to exposed areas. Bauder AP3 This is a rigid 3 mm polymeric composite board for horizontal and vertical surfaces. It is used for heavy landscaping, tarmac and areas requiring substantial protection. 79 bauder. co. uk Image courtesy of IRT Surveys TECHNICAL GUIDE