Module INS-01Module TAP01 COMMERCIAL ROOFING Tapered Insulation Systems

Module INS-01Module TAP01 Learning Objectives Tapered Insulation Presentation  Tapered insulation – what is it?  Why do we use it?  Various designs from good to best  Crickets function and design  Specifying a good design

Module INS-01Module TAP01 What, Why, and How? Tapered Insulation Systems

Module INS-01Module TAP01 Tapered Insulation  Rigid roof insulation  Made from various materials Polyiso Extruded & Expanded Polystyrene Perlite  Typically 2x4 or 4x4 panels  Provides r-value and slope  Typical slopes available 1/8”/ft., ¼”/ft., ½”/ft.  Arranged by a designer into a tapered system to promote positive drainage

Module INS-01Module TAP01 Why use a tapered insulation system?  Main Goal  Eliminate the amount of ponding/standing water on the membrane when the roof deck does not provide adequate slope

Module INS-01Module TAP01 Ponding may void the roofing warranty Why is it Important?

Module INS-01Module TAP01 Prevents the potential for roof collapse from excess weight Why is it Important?

Module INS-01Module TAP01 Prevents growth of vegetation, fungi, and bacteria. Why is it Important?

Module INS-01Module TAP01 Why is it Important? Extends the overall life of a roofing system.

Module INS-01Module TAP01 Why is it Important?  National Agencies & Code Groups require a minimum slope ¼”/ft. minimum in most cases Provided by structure or a tapered insulation system Ponds existing after 48 hours not acceptable to any of the major code bodies

Module INS-01Module TAP01 Tapered Insulation Designs  Numerous possible designs even for the simplest roof  Individual job parameters determine which design is the best option 4-way slope Modified 4-way slope with cricket Valley & Cricket

Module INS-01Module TAP01 One Way Slope to Gutter  Most basic design  Simple installation

Module INS-01Module TAP01 Two Way Slope to Gutter  Second most basic design  Roof is cut in half which reduces the maximum thickness  Simple installation Ridge

Module INS-01Module TAP01 Valley and Cricket to Drain  Commonly used design with drains  Cheapest material cost in most cases (versus 4- way slope design)  Potential small ponding along cricket edges (typical)  Not the most effective drainage design Potential ponding area

Module INS-01Module TAP01 Modified 4-Way Slope to Drains  Second most effective drainage  Used when no overflow drains exists  If one drain is clogged the water can flow over to other drain

Module INS-01Module TAP01 4-Way Slope Design  Most effective drainage design (any compromise will effect performance)  Every tapered system should start with this design  Next step is to identify justifiable reasons to alter this layout

Module INS-01Module TAP01 Common Attempt to Show a 4-Way Slope Design Randomly drawn valley lines at no specific angles

Module INS-01Module TAP01 Correct Way to Show a 4-Way Slope Design Zoom Window

Module INS-01Module TAP01 4-Way Slope Design Zoom Window Valley Lines should be drawn at a 45 degree angle out of each drain

Module INS-01Module TAP01 45 Degree Valley Miter 45 degree angle

Module INS-01Module TAP01 4-Way Slope Design

Module INS-01Module TAP01 Reasons to Alter 4-Way Design Complex existing drain locations

Module INS-01Module TAP01 Reasons to Alter 4-Way Design Constant perimeter height is required

Module INS-01Module TAP01 Reasons to Alter 4-Way Design Multiple drains at low point with no overflow drains Overflow drains added

Module INS-01Module TAP01 Reasons to Alter 4-Way Design When cost is a bigger issue than performance 4-Way Design -Most effective drainage -Higher material cost Valley & Cricket Design -Least effective drainage -Lower material cost

Module INS-01Module TAP01 Reasons to Alter 4-Way Design Multiple roof top units prevent layout from draining

Module INS-01Module TAP01 Tapered Cricket Tapered Crickets  Used on both: Full tapered systems Structurally sloped decks

Module INS-01Module TAP01 Tapered Cricket Tapered Crickets  Also called: Saddles Hog Backs

Module INS-01Module TAP01 Tapered Crickets  Secondary application of insulation used to divert water from roof top curbs, valleys, and low points to drains or scuppers Tapered Crickets

Module INS-01Module TAP01 SLOPE OF TAPER SLOPE OF CRICKET Secondary application of insulation used to divert water from roof top curbs, valleys, and low points to drains or scuppers RAIN Tapered Crickets

Module INS-01Module TAP01 Tapered Crickets

Module INS-01Module TAP01 Types of Crickets

Module INS-01Module TAP01 Types of Crickets

Module INS-01Module TAP01 ½ - Diamond Cricket Types of Crickets

Module INS-01Module TAP01 Types of Crickets

Module INS-01Module TAP01 Types of Crickets

Module INS-01Module TAP01 Incorrectly drawn crickets Correctly drawn crickets Tapered Crickets

Module INS-01Module TAP01 Tapered Crickets

Module INS-01Module TAP01 4x4 Tapered panel Portion of tapered panel that is field trimmed as waste Crickets are created in the field by field trimming tapered panels as shown Tapered Crickets

Module INS-01Module TAP01 Tapered Crickets

Module INS-01Module TAP01 Tapered Crickets Full Diamond Cricket Installed 4x4 Tapered Panels Full Diamond CricketUninstalled Portion

Module INS-01Module TAP01 Tapered Crickets RTU

Module INS-01Module TAP01 Tapered Crickets

Module INS-01Module TAP01 Parts of a Tapered Cricket Cricket Width (Points 4 to 5)

Module INS-01Module TAP01 Parts of a Tapered Cricket Cricket Length (Points 1 to 2)

Module INS-01Module TAP01 Parts of a Tapered Cricket The slope that is created by the structural deck, tapered insulation or a combination of the two.

Module INS-01Module TAP01 Parts of a Tapered Cricket The slope of the cricket panels. Recommended to be at least twice the net Roof Surface Slope that exists. This ensures that the water is directed into the cricket valley.

Module INS-01Module TAP01 Parts of a Tapered Cricket The net slope created along the edges of the cricket. (Points 4 to 1, 4 to 2, 5 to 2, & 5 to 1) This directs the water to the drains.

Module INS-01Module TAP01 Tapered Cricket Tapered Crickets  Caution! If not designed properly crickets can pond

Module INS-01Module TAP01 Three Main Contributors to the Working Effectiveness of a Cricket Cricket Valley Slope Cricket Surface Slope Cricket Width Cricket Valley Slope Roof Surface Slope 1. Roof Surface Slope Crickets divert water, so the greater the Roof Surface Slope the better they will perform!

Module INS-01Module TAP01 Three Main Contributors to the Working Effectiveness of a Cricket Cricket Valley Slope Cricket Surface Slope Cricket Width Cricket Valley Slope Roof Surface Slope 2. Cricket Surface Slope The Cricket Surface Slope pushes the water into the Cricket Valley. Therefore it should be at least twice the Roof Surface Slope!

Module INS-01Module TAP01 Three Main Contributors to the Working Effectiveness of a Cricket Cricket Valley Slope Cricket Surface Slope Cricket Width Cricket Valley Slope Roof Surface Slope 3. Cricket Width!! A WIDER CRICKET IS BETTER! The most important factor in cricket performance! The wider the cricket is made the better the resulting Cricket Valley Slope.

Module INS-01Module TAP01 Calculating Cricket Valley Slope Step #1 Step #2 Step #3 Step #4 Step #5

Module INS-01Module TAP01 Getting an Accurate and Functional Tapered Design  Be clear and concise so that “guessing” by the tapered designer and contractor is eliminated!

Module INS-01Module TAP01 General Required Information to Insure Accurate Designs  Dimensions of building perimeter  Number and location of drains  Mechanical unit, skylight and roof penetration locations  Expansion and control joint locations  Existing height restrictions  Existing unique field conditions Provide accurate information about:

Module INS-01Module TAP01 What Else Can You Do? Add charts to the roof plan page to clearly designate what insulation should be provided for each roof area.

Module INS-01Module TAP01 What Else Can You Do? Use a Roof Legend to clearly label existing conditions and to call out what is needed and where.

Module INS-01Module TAP01 What Else Can You Do? Specify whether slope arrow is designating a required tapered slope or an existing structural slope. Note desired minimum and maximum thickness. Note all components that are included in thickness shown.

Module INS-01Module TAP01 What Else Can You Do? Note desired cricket widths on roof plan.

Module INS-01Module TAP01 Locating Roof Drains  Locate as close to the low point as possible  Locate them symmetrically and in line with each other  Space drains using 2’ or 4’ increments due to modular sizes of tapered panels

Module INS-01Module TAP01 Locating Roof Drains  One drain for every 5000 square feet of roof area  75 feet maximum distance between drains  Sizes are determined by roof area and average rainfall data

Module INS-01Module TAP01 Locating Roof Drains  Provide overflow drain no more than 2” above primary  Avoid having roof top units or penetrations near drains

Module INS-01Module TAP01 Summary  The goal is to drain water from the roof!  Several tapered designs possible  Use 4-way slope design as often as possible  Draw lines at 45 degree angles from drains  Crickets divert water  3 main factors to cricket performance: roof surface slope, cricket valley slope, and cricket width

Module INS-01Module TAP01 Summary  Be clear and concise on drawings and specifications  Provide as much information as possible  Locate drains symmetrically and in line as often as possible  Never space drains more than 75 feet apart  Always have a backup drain

Module INS-01Module TAP01 Summary  You are in control of the project  Make sure submitted shop drawings reflect the tapered design that you want  Reject Non 4-way layouts if that is what you showed in your bid documents  Reject layouts that shrink the cricket widths shown in your bid documents  You have the power to make sure the most EFFECTIVE tapered design is submitted and installed

Module INS-01Module TAP01 QUESTIONS? This concludes the American Institute of Architects Continuing Education Systems Program Firestone Building Products

Module INS-01Module TAP01