Reflective Insulation

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Reflective Insulation Radiant Barriers
R-Values Thermal Performance -

• Presented on Behalf of RIMA

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About RIMA

• The Reflective Insulation Manufacturers
• Association represents manufacturers and
• distributors of reflective insulation, radiant
  barriers and interior radiation control coating
  materials.
• RIMA activities are guided by an active board of
  industry members who participate on national and
  local levels of building code organizations and
  governmental agencies.
• Visit us at www.rima.net.

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RIMA Members

• Advanced Technology, Inc.
• Air-Cell Innovations Pty Ltd
• Astro Reflective Insulation AS
• Celplast Metallized Products
• Cleveland Laminating Corp
• Compac Corporation
• Dunmore Corporation
• DuPont Tyvek
• Heartland Insulation Supply
• Ideal Tape Company Inc
• Innovative Energy, California
• Innovative Insulation Inc.
• Insulation Solutions, Inc.
• Isolant S.A.
• LIT Works Co.

Louisiana Pacific Midwest Low-E MWI
Components Polyair Polyon Barkai Ind. Prodex PT
Insfoil Pradanasakti Radiant Guard Resisto, a
Div. of Soprema Saeyoung Polymer Co. San Miguel
Woven Product Sigma Technologies
Intl Solec Valeron Strength Films Venture Tape
Corp YBS Insulation Ltd.

• Platinum Members
• Astro-Foil - Innovative Energy
• Covertech
• ESP, Inc.
• Fi-Foil Company
• KdB Isolation SA
• Martco Limited Partnership
• Reflectix Inc
• TVM Building Products

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Overview

• Installation
• R-Values, U-Factors and Thermal Performance of
  Reflective Insulation
• QA

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• Installation

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• Installation of Reflective Insulation Systems
• Metal Buildings

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• Metal Buildings New

Various Widths Lightweight With or without
Mass Insulation Aluminum on One or Both Sides
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New Construction RoofWith and Without Thermal
Breaks
Cross Section with Thermal Breaks and Designed
Reflective Air Space
Low Emittance Air Film
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• Metal Buildings Ceilings
• New or Existing

Over-lapped on Bottom
Furred-out Across the Purlins
Installed with the Purlins
Back-filled with Mass Insulation
Thermal Break Vapor Retarder
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Vapor RetarderSealing the Seams

• Options
• Staple Together
• Silicone Between Tabs
• Double sided tape between Tabs
• Foil Tape over seam

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• Metal Buildings Ceilings
• New or Existing

Sealed Seams Easily Trimmed
Obstructions are easily over-come
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New Construction Walls
Low Emittance Surface Back-loaded with Mass
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• Metal Buildings - Walls

Furred-out Installed Perpendicular to Girts
Install with Girts
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• R-Values, U-Factors, and Thermal Performance of
  Reflective Insulation

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Thermal Resistance
R-Values

• Are used to compare thermal insulation products
• Quantify resistance to heat flow
• Are used to calculate heating and cooling loads
• Can be measured for specific conditions
• Can be determined from physical property or
  system measurements

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Many Insulations Derive Performance from the Low
Thermal Conductivity of Air

• Air-Based Insulations Non-Air Based Insulations
• Cellulose Closed Cell Foams
• Fiberglass
• Rock Wool Evacuated Panels
• Perlite Gas-Filled Panels
• Open-Cell Foams Nano-Scale Materials
• Reflective Insulations - Enclosed Air spaces
• Radiant Barriers - Open Air Spaces

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Air-Based Insulations Have Limits

• The maximum R-Values occurs when radiation and
  convection are absent.
• T ( F) k of AIR R per Inch
• -25 0.148 6.8
• 25 0.163 6.1
• 75 0.178 5.6
• 125 0.193 5.2
• These R/Inch limits apply to both conventional
  and reflective insulations.

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How Do Reflective Insulation Systems Fit Into
This Framework?

• Take advantage of the low thermal conductivity of
  air
• Use enclosed air spaces with low emittance
  surfaces
• Have a mass insulation component in many cases
• Aluminum foils or films have emittances in the
  range 0.03 to 0.05 ( The scale for emittance
  is 0 to 1 )
• Emittance is a measurement of how efficiently a
  surface gives off radiant heat. The lower the
  emittance the better !
• Reflectance is the fraction of incoming radiation
  that is not absorbed by a surface. The higher the
  value the better.
• In the case of opaque materials
  reflectanceemittanceone

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R-Values for Reflective Insulations and Mass
Insulations are Determined by Different Methods

• Start with the 1-D steady-state form of
• Fouriers Law - Q -kAdT/dX
• Written in practical form - Q kA?T/L
• Rearranged - k QL/A?T
• and R L/k ASTM C 518
• Heat Flow Meter
• also R A?T/Q ?T/q
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  ASTM C 1363
• Hot Box Facility
• In both cases the R has units ft2hF/Btu
• The R-values for conventional mass insulations
  increase in direct proportion to the thickness of
  the insulation.
• Reflective insulation has a complex thickness
  dependence

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U-Factor Determination

• QUA?T
• Direct measurement using ASTM C 1363 Hot Box
  Facility
• Calculations based on properties
• series-parallel (an
  approximation)
• modified zone method
  (recommended)
• Zone Method
• Path 1 Path 2
• Purlin (low R) Between
  Purlin (high R)
• Mathematical Combination of Results
• Adding R to Path 1 has greater effect than adding
  R to Path 2.
• A continuous layer adds to both paths
• U-factor includes air film resistances
• Low-e improves the air film resistance
• ASHRAE 90.1 provides details

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Hybrid Strategies

• Enclose the space below the R 19 batt insulation
  to form a reflective air space.
• Install RI above the purlins to produce a
  reflective air space between the mass insulation
  and the roof panels.
• Both strategies increase the thermal resistance
  between the purlins and add a continuous layer of
  insulation.

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Calculated R for Enclosed Air Space
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Air Film Resistances (IP Units)

• From ASHRAE 90.1
  
• Exterior 0.17
• Interior
• Heat flow up 0.61
• Heat flow down 0.92
• Horizontal 0.68
• From ASHRAE Handbook of Fundamentals
• Interior High Emittance Low
  Emittance
• Heat flow up 0.61 1.32
• Heat flow down 0.92 4.55
• Heat flow horizontal 0.68 1.70

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Assembly U-Factors for Metal Building Roofs

• Table A2.3 ASHRAE 90.1
• standing seam with one-inch block
• single Layer
• Rated R of Insulation U-Factor Rated R for
  Continuous Layer
• R-5.6 R-11.2 R-16.8
• 16 0.072 0.051 0.040 0.033
• 19 0.065 0.048 0.038 0.031
• 
  
• Add RI to increase Rated R and add continuous
  layer.

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An Example of the U that can be Achieved

• Enclose the region below draped R 19 batt
  insulation
• Heat flow down this adds R 7
• Adds a continuous layer of about 5.6 (air film
  material R-value)
• Adds R 2 in path of purlin
• Using Table A2.3 (90.1) to estimate new values
  
• U 0.042
• R 30 with no continuous layer U 0.051
• R 30 with R 5.6 continuous layer U 0.040

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SUMMARY

• Enclosed reflective air spaces can be used to
  form hybrid metal building insulation systems.
• Continuous added R can be achieved.
• Hybrid systems provide a way to satisfy new
  thermal resistance requirements for metal
  buildings.

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• Questions?
• Call
• Reflective Insulation
• Manufacturers Association (RIMA)
• 4519 E. Lone Cactus Drive
• Phoenix, AZ 85050
• 800/279-4123
• www.rima.net