BS 8747:2007
$167.15
Reinforced bitumen membranes (RBMs) for roofing. Guide to selection and specification
| Published By | Publication Date | Number of Pages |
| BSI | 2007 | 38 |
This British Standard gives guidance to assist the selection and specification of a system of appropriate layer(s) of reinforced bitumen membrane (RBM) for each flat and/or sloping roofing project, tailored to the particular requirements of that project.
It provides a grouping system to assist the specifier, utilizing material properties as tested according to BS EN 13707.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 3 | Contents Introduction – CEN test methods referenced in this standard 1 1 Scope 1 2 Normative references 2 3 Terms and definitions 2 4 Membrane selection guidelines 5 5 System selection 16 6 Bonding and installation of an RBM 18 Annexes Annex A (informative) CE marking information for an RBM product 20 Annex B (informative) Guide to specifying RBM equivalent to Type 1F or Type 5U reinforced bitumen roofing underlay 21 Annex C (informative) Guide to specifying RBM equivalent to Type 3G glass-fibre reinforced bitumen perforated venting layer 23 Annex D (informative) Worked examples 24 Bibliography 32 List of tables Table 1 – Tensile strength of membrane classes 12 Table 2 – Resistance to impact 12 Table 3 – Resistance to static loading 12 Table 4 – Combinations of D subclass and L subclass to give P class 12 Table 5 – Membrane classification by performance requirement 14 Table 6 – Comparison between BS 747 membranes and the SNPN system 15 Table 7 – Flow chart for system selection – Warm deck roofs 16 Table 8 – Flow chart for system selection – Inverted warm roofs 18 Table B.1 – Mass per units area for constituents of Type 1F and Type 5U RBMs 22 Table C.1 – Mass per units area for constituents of Type 3G RBMs 24 |
| 4 | Foreword |
| 5 | Introduction – CEN test methods referenced in this standard 1 Scope |
| 6 | 2 Normative references 3 Terms and definitions 3.1 built-up reinforced bitumen membrane built-up RBM 3.2 single-layer reinforced bitumen membrane single-layer RBM |
| 7 | 3.3 access roof 3.4 base layer preparatory layer 3.5 bonding bitumen 3.6 capsheet 3.7 carrier 3.8 cold deck roof cold roof 3.9 detailing capsheet 3.10 full bonding 3.11 gritting solution 3.12 intermediate layer 3.13 inverted roof upside-down roof protected membrane roof |
| 8 | 3.14 manufacturer’s declared value MDV 3.15 manufacturer’s limiting value MLV 3.16 partial bonding 3.17 roof deck 3.18 substrate 3.19 tapered insulation 3.20 terrace roof 3.21 top layer 3.22 vapour control layer VCL 3.23 warm deck roof warm roof |
| 9 | 4 Membrane selection guidelines 4.1 General 4.2 Principles |
| 10 | 4.3 Caveats |
| 11 | a) Location: when considering a tower block in an exposed area, e.g. Scotland, wind uplift resistance and therefore tensile strength S and attachment method should be of major concern. b) Purpose: with a heavily trafficked low-level roof area in a sheltered area, the puncture resistance P (both static and dynamic) will be more important. c) If the roof is likely to be subject to vandalism and damage, then the puncture resistance P (both static and dynamic) would again be important. d) Expected service life: if access to the roof is difficult, then the area may only rarely be inspected or maintained, thus requiring the use of a higher classified material (following the SP system [4.8]). 4.4 Types of RBM for roofing 4.4.1 RBM with oxidized bitumen 4.4.2 RBM with SBS-modified bitumen (elastomeric) |
| 12 | 4.4.3 RBM with APP-modified bitumen (plastomeric) 4.5 Pre-filtering 4.6 Relevant product data 4.6.1 General 4.6.2 Tensile strength (S) |
| 13 | 4.6.3 Elongation 4.6.4 Nail shank tearing test 4.6.5 Static load resistance (L) 4.6.6 Impact resistance (D) |
| 14 | 4.6.7 Flexibility at low temperature (pliability) 4.6.8 Flow resistance at elevated temperatures 4.6.9 Durability 4.6.10 External fire performance 4.6.11 Reaction to fire |
| 15 | 4.7 Reinforced bitumen membrane (RBM) classification 4.8 The SP classification system for RBMs in roofing 4.8.1 Introduction a) the performance achieved by any particular membrane; and b) the performance required by any particular roof construction. 4.8.2 General a) tensile strength S; and b) resistance to puncture or indentation P. 4.8.3 Classification of the membrane 4.8.3.1 Principle |
| 16 | 4.8.3.2 Tensile strength (S) Table 1 Tensile strength of membrane classes 4.8.3.3 Puncture or indentation (P) Table 2 Resistance to impact Table 3 Resistance to static loading Table 4 Combinations of D subclass and L subclass to give P class |
| 17 | 4.8.4 Classification of the membrane performance requirements 4.8.5 Use of Table 5 |
| 18 | Table 5 Membrane classification by performance requirement |
| 19 | Table 6 Comparison between BS 747 membranes and the SNPN system 4.9 Other significant criteria 4.9.1 Introduction 4.9.2 Elongation 4.9.3 Nail shank tearing 4.9.4 Flexibility at low temperature 4.9.5 Flow resistance at elevated temperatures 4.9.6 Durability |
| 20 | 5 System selection Table 7 Flow chart for system selection – Warm deck roofs |
| 21 | Table 7 Flow chart for system selection – Warm deck roofs (continued) |
| 22 | Table 8 Flow chart for system selection – Inverted warm roofs 6 Bonding and installation of an RBM 6.1 General a) fully bonded in poured hot bitumen; b) partially bonded in poured hot bitumen; c) fully bonded by torching; d) partial bonding by torching; e) cold bituminous or other specialist adhesives; f) self-adhesive membranes; g) mechanical fixing; and h) loose laid and ballasted roofs. |
| 23 | 6.2 Sloping roofs and vertical work 6.3 Installation of vapour control layers (VCLs) |
| 24 | Annex A (informative) CE marking information for an RBM product A.1 General A.2 Example of CE marking information |
| 25 | Annex B (informative) Guide to specifying RBM equivalent to Type 1F or Type 5U reinforced bitumen roofing underlay B.1 Introduction B.2 Characteristics of Type 1F reinforced bitumen roofing underlay B.2.1 Description B.2.2 Uses B.2.3 Details of constituent materials |
| 26 | B.2.4 Characteristics of Type 5U polyester reinforced bitumen roofing underlay Table B.1 Mass per units area for constituents of Type 1F and Type 5U RBMs |
| 27 | Annex C (informative) Guide to specifying RBM equivalent to Type 3G glass-fibre reinforced bitumen perforated venting layer C.1 Introduction C.2 Characteristics of Type 3G glass-fibre reinforced bitumen perforated venting layer C.2.1 Description C.2.2 Details of Constituent Materials C.2.3 Uses C.2.4 Mass |
| 28 | C.2.5 Standard packages Table C.1 Mass per units area for constituents of Type 3G RBMs Annex D (informative) Worked examples D.1 Introduction |
| 36 | Bibliography [1] EUROPEAN COMMUNITIES. 89/106/EEC. Council Directive of 21 December 1988 on the approximation of laws, regulations and admini… |
