ROOFING AND WATERPROOFING

0,22
MB

93
stron

6375
ID UNITED STATES ARMY CORPS OF ENGINEERS

1997
rok

CONTENTS

Section 1 INTRODUCTION

1.1 Scope 1

1.2 Roof Design Synthesis 1

1.3 Roof-Mounted Equipment . 1

1.4 Climatic Conditions 1

1.4.1 Solar Radiation 2

1.4.2 Wind Velocity 2

1.5 Roofing Material Selection . 2

Section 2 STRUCTURAL DECK

2.1 Functions 4

2.2 Design Factors . 4

2.2.1 Drainage . 4

2.2.2 Deflections 5

2.2.3 Expansion Joints . 5

2.2.4 Roof Assemblies 6

2.2.5 General Precautions 6

2.3 Precautions for Specific Roof Decks 6

2.3.1 Precast Concrete Panel Roof Decks 6

2.3.2 Prestressed Precast Concrete Roof Decks 6

2.3.3 Wood Board or Plywood Roof Decks . 6

2.3.4 Cement-Wood Fiber Panel Roof Decks . 6

2.3.5 Poured Gypsum Concrete Roof Decks 7

2.3.6 Lightweight Insulating Concrete Fills 7

Section 3 THERMAL INSULATION

3.1 Purposes for Insulation 9

3.2 Design Factors . 9

3.2.1 Compressive Strength . 9

3.2.2 Moisture Absorption 9

3.2.3 Dimensional Stability 9

3.2.3.1 Temperature 9

3.2.3.2 Moisture . 10

3.2.3.3 Dimensional Compatibility 10

3.2.4 Compatibility 10

3.2.5 Thickness 10

3.2.5.1 Layering . 10

3.2.6 Design Criteria 10

3.2.6.1 Documents 11

3.2.6.2 Variations . 11

3.2.7 valuation 11

3.2.7.1 ASHRAE Methods . 11

3.2.7.2 Life Cycle Cost 11

3.2.7.3 Important Considerations . 11

3.2.8 Location . 12

3.3 Materials 12

3.3.1 Board Insulation . 12

3.3.2 Insulating Concrete 12

3.3.3 Sprayed Plastic Foam . 12

3.3.4 Properties . 12

3.4 Tapered Insulation . 13

3.5 Application Criteria . 13

Section 4 VAPOR CONTROL

4.1 Psychrometrics . 14

4.1.1 Vapor Pressures and Flow . 14

4.1.1.1 Indoor . 14

4.1.1.2 Outdoor 14

4.1.1.3 Design Criteria 14

4.1.2 Dewpoint . 14

4.1.3 Influence on Roof 15

4.2 Vapor Control Methods 15

4.2.1 Vapor Resistance . 15

4.2.1.1 Materials 15

4.2.1.2 Calculations . 15

4.2.1.3 Location . 15

4.2.1.4 Application 16

4.2.2 Ventilation 16

4.2.2.1 Below Insulation . 16

4.2.2.2 Above Insulation . 16

Section 5 BITUMINOUS BUILT-UP ROOF MEMBRANE

5.1 Material Description . 17

5.1.1 Bitumen 17

5.1.2 Felts 17

5.1.3 Surfacing 17

5.1.4 Flashing . 17

5.1.4.1 Base Flashings . 17

5.1.4.2 Counterflashings . 17

5.2 General Requirements . 18

5.2.1 Felts 18

5.2.2 Modified Bitumen Flashing 18

5.2.3 Compatibility 18

5.3 Membrane Design Recommendations 18

5.3.l Bitumen Slope Limits . 18

5.3.2 Flashing Design Principles . 18

5.3.2.1 Differential Movement 19

5.3.2.2 Contour Flashings 19

5.3.3 Foot Traffic . 19

5.3.4 Details 20

Section 6 SINGLE-PLY ROOFING SYSTEMS

6.1 Single-Ply Roofing Description . 21

6.1.1 Single-Ply Sheet-Applied Materials . 21

6.1.1.1 Elastomeric Sheets . 21

6.1.1.2 Plasticized Thermoplastic Sheets . 21

6.1.1.3 Uncured Elastomers . 22

6.1.1.4 Modified Bitumens 22

6.1.2 Liquid-Applied Coatings 23

6.1.2.1 Uses . 23

6.1.2.2 Advantages . 23

6.1.2.3 Disadvantages 23

6.2 Perimeter Anchorage 23

6.3 Design Requirements/Considerations . 24

6.3.1 Single-Ply Roofs . 24

6.4 Applicable Details . 25

6.5 Single-Ply Membrane Standards 25

Section 7 SPRAYED POLYURETHANE FOAM

7.1 Material Description . 26

7.2 Uses . 26

7.2.1 Advantages . 26

7.2.2 Disadvantages 27

7.3 Design Recommendations . 27

7.3.1 Foam Thickness and Slope . 28

7.3.2 Control Joints . 28

7.3.3 Membrane Coatings 28

7.4 Application Considerations . 29

7.5 Flashings 29

7.6 Applicable Details . 29

Section 8 PROTECTED MEMBRANE ROOF SYSTEM

8.1 Description 30

8.2 General Design Recommendations . 30

8.2.1 Structural Capacity 30

8.2.2 Slope 30

8.2.3 Water-Test . 30

8.2.4 Climate 30

8.3 Specific Design Recommendations 31

8.3.1 Drainage . 31

8.3.2 Percolation Course . 32

8.3.3 Flashings 32

8.4 Variations . 32

8.5 Other Considerations . 32

8.5.1 Single-ply or Liquid Membrane 32

8.5.2 Expansion Joint 32

8.6 Applicable Details . 33

Section 9 STEEP ROOFING

9.1 Steep Roofing Description 34

9.2 Materials 34

9.3 General Design Requirements 34

9.3.1 Slopes . 34

9.3.2 Decks 34

9.4 Underlayments 34

9.4.1 Underlayments for Steep Roofing 35

9.4.2 Underlayment for Wood Shake, Clay Tile, and Concrete Tile Roofs 35

9.5 Ventilation 37

9.5.1 Vents 37

9.6 Anchorage Techniques . 37

9.6.1 Fasteners 37

9.6.2 Special Anchorage 37

9.6.3 Anchorage in Hurricane or High-wind Zones 37