BS CP143-16(1974) : LATEST

Foreword
1. GENERAL
1.1 Scope
1.2 Definitions
1.3 Exchange of information and time schedule
2. MATERIALS AND COMPONENTS
2.1 Semi-rigid asbestos bitumen sheet (SRABS)
2.2 Jointing compounds and adhesives
2.3 Ribbed strips
2.4 Roll capping
2.5 Flashings, anchor strips, gutters, outlets, etc.
2.6 Nails
2.7 Screws
2.8 Tools and equipment
3. DESIGN CONSIDERATIONS
3.1 SRABS roofing systems
3.2 Characteristics of semi-rigid asbestos bitumen
      sheet
3.3 Durability
3.4 Properties affecting design
3.5 Roof pitch
3.6 Gutter fall
3.7 Roof decks
3.8 Joints
3.9 Special features
3.10 Thermal insulation
3.11 Fire protection
3.12 Wind loading
3.13 Condensation
4. METHOD OF LAYING AND WORKMANSHIP
4.1 Protection and storage on site
4.2 Preparatory work
4.3 Sequence of operation
4.4 Preparing and making a sealed joint
4.5 Setting out
4.6 Laying procedure
4.7 Flashings
5. INSPECTION AND MAINTENANCE
5.1 Inspection
5.2 Maintenance
APPENDIX
A. Typical physical properties of SRABS
TABLE
1. Jointing compounds
FIGURES
1. Typical layout for roll-cap system, with drips
2. Typical layout for roll-cap system, without drips
3. Typical layout for rib system
4. Section through ribbed base and cover strips
5. Section through roll-capping
6. Making a delaminated joint
7. Making a No.3 or No.4 lap joint
8. Making a No.20 lap joint
9. Anchor strip at eaves
10. Sheet half-stops and roll-capping stop end at eaves
11. Corner piece at drip against sidewall
12. Folded offset on roll-capping
13. Folded saddle on roll-capping
14. Finish to wood roll at verge
15. Patterned application of adhesive No.10, under
      2400 mm x 900 mm or 1200 mm x 900 mm SRABS
16. Spigot jointed to gutter lining
17. Additional sheet fixings on roofs above 60 deg
      pitch
18. Welted eaves edge, rib system
19. Internal corner, in upstand section
20. External corner, in upstand section
21. Lining to box or parapet gutter
22. Lining forming valley
23. Ribbed base strip in position
24. Sheets laid at eaves
25a. Cover strip in position
25b. Drip edge turned down
26. Cover strip at gutter or valley
27. Cover strip at ridge or hip
28. Upstand section in position
29. Finish at verge, with water check
30. Cover flashing
31. Expansion joint flashing
32. Weathering a projection through roof using the
      sealed-lap jointing method

Describes semi-rigid asbestos bitumen sheet roof coverings and gives recommendations based on accepted good practice for laying fully supported semi-rigid asbestos bitumen sheet roofs using the roll cap and rib systems. Recommendations are given for the whole of the roof covering above the upper surface of the constructional base for both flat and pitched roofs. Flashing and gutters are dealt with in so far as they are integral parts of the roof covering.