View source for Template:Part 8 - PVC

__NOTOC__
<div id="INSUL_OVERLAY_DESIGN"></div>
==Design==
(See [[Notes to PVC Standard#A-8.1 | Note A-8.1]])

===General===
====Scope====
<ol>
<li>The scope of this Part and the Standard shall be as described in Part 1 of Division A in this ''Manual''.
</li></ol>

====Definitions====
<ol>
<li>Words that appear in italics are defined in the [http://rpm.rcabc.org/index.php?title=Glossary '''Glossary'''].
</li></ol>

===Guarantee Term Requirements===
====RoofStar 5-year and RoofStar 10-year Guarantee====
<ol>
<li>All ''projects'' intended to qualify for a '''''RoofStar 5-year''''' or '''''RoofStar 10-year Guarantee''''' shall comply with the requirements in this Part.
</li></ol>

====RoofStar 15-Year Guarantee====
<ol>
<li>All ''projects'' intended to qualify for a '''''RoofStar 15-year Guarantee''''' shall comply with the requirements in this Standard for a '''''RoofStar 5-year''''' or '''''RoofStar 10-year Guarantee''''', together with the following:
<ol>
<li>An insulation overlay is required for all insulated ''systems'', regardless of the insulation type, and overlays must
<ol>
<li>be at least 6.4 mm (1/4”) thick, and
<li>possess a compressive strength of at least 690 kPa (100 psi).
</li></ol>
</li></ol>
</li></ol>

===All Systems===
====Use Over Sensitive Materials and Systems====
<ol>
<li>{{hilite |Notwithstanding the requirements in '''Part 7''' concerning ''heat-sensitive insulation''|| 2021-June-30 }}, an insulation overlay of one or more layers is required over {{hilite | all flat and sloped ||2021-June-30 }} board-type insulation, {{hilite | and on insulation installed on vertical surfaces|| 2021-June-30 }},
<ol>
<li>{{hilite | if the compressive strength of the insulation is less than 110 KPa (20 psi)|| 2021-February-7 }},
<li>{{hilite | if the membrane {{hilite | is self-adhered or|| 2021-June-30 }} will be applied with a torch flame, adhesives or hot bitumen|| 2021-February-7 }}, or
<li>if a ''Conventionally Insulated System'' supports an overburden; these ''roof systems'' must be designed with at least one layer of adhered {{hilite | overlay (asphaltic overlays, moisture resistant fibreglass-faced silicon treated gypsum core overlays, high-density insulation overlays, composite or membrane-laminated overlays) capable of supporting any superimposed loads on the exposed membrane, without compression or distortion of the roof system or any one of its components (see also Article 14.1.2.1|| 2022-June-17}}).
</li></ol>
<li>{{hilite | The requirement to use an insulation overlay does not apply to the field application of|| 2021-June-18 }}
<ol>
<li>{{hilite | self-adhered membranes|| 2021-June-30 }}
<ol>
<li>{{hilite | expressly accepted by the '''''Guarantor''''' for application directly on specific insulation types without the use of an overlay|| 2021-June-30 }}, or
<li>{{hilite | expressly approved (in published literature) by the manufacturer for application directly on an insulation panel|| 2021-June-30 }}.
</li></ol>
</li></ol>
<li>{{hilite | ''Heat-sensitive'' crickets used in membrane systems applied with a torch flame or hot bitumen must be overlaid using either|| 2021-June-18 }}
<ol>
<li>one layer of panels,
<ol>
<li>at least 12.5 mm (1/2”) thick,
<li>offset from insulation joints by at least 300 mm (12”), and
<li>continuously sealed with a flame-impervious tape along all joints with adjacent panels, or
</li></ol>
<li>two layers of panels,
<ol>
<li>each at least 4.8 mm (3/16”) thick, and
<li>offset from each other, from the adjacent layer, and from insulation joints by at least 300 mm (12”).
</li></ol>
</li></ol>
</li></ol>
</li></ol>

====Use Over Mineral Fibre Insulation====
<ol>
<li>{{hilite | An insulation overlay is not required when torch-applied membranes are installed directly on mineral fibre insulation treated with a thermofusible bitumen top surface (This exception is subject to the requirements for mineral wool insulation published in '''Part 7 INSULATION''')|| 2022-October-22 }}.
<li>{{hilite | When an overlay board is required over mineral wool insulation, the overlay board must be a moisture resistant fibreglass-faced silicon treated gypsum core board measuring at least 12.7 mm (1/2") thick (See also '''7.2 Materials''' concerning mineral wool insulation)|| 2022-October-22 }}.
</li></ol>
<div id="INSUL_OVERLAY_MATERIALS"></div>

==Materials==
(See [http://rpm.rcabc.org/index.php?title=Division_C:_Accepted_Materials '''Division C: Accepted Materials'''])

===Material Properties===
====Insulation Overlay Dimensions====
<ol>
<li>Regardless of the type of insulation overlay, the overall thickness of insulation overlay boards shall not exceed 50 mm (2”) (See minimum allowable thicknesses are shown in '''Table 8.1''').
<li>{{hilite | Asphalt-coated|| 2021-June-30 }} fibreboard roof insulation adhered with hot asphalt or an asphalt-based adhesive must be asphalt-coated on the top and bottom surface (Minimum coated two-sides).
<li>Fire guard tape must be 150 mm (6”) wide
<ol>
<li>self-adhering modified bituminous tape acceptable to the membrane manufacturer, or
<li>Type IV fibreglass felt or No. 15 organic felt, applied with hot bitumen or cold adhesive.
</li></ol>
</li></ol>

:{| class="wikitable"
|+ Table 8.1 Insulation Overlay Minimum Thicknesses
|-
! style="width: 450px;vertical-align:centre;text-align:center;" | Overlay Type
! style="width: 220px;vertical-align:centre;text-align:center;" | Minimum Thickness - mm (in.)
|-
| Asphaltic core || style="width: 100px;vertical-align:top;text-align:center;"   | 4.8 (3/16")
|-
| Moisture resistant fibreglass-faced silicon treated gypsum core ||  style="width: 100px;vertical-align:top;text-align:center;"   | 6.4 (1/4")
|-
| High-density insulation || style="width: 100px;vertical-align:top;text-align:center;"   |  12.7 (1/2")
|-
| Membrane-laminated overlays and Composites || style="width: 100px;vertical-align:top;text-align:center;"   | As listed in this ''Manual''
|-
| Fibreboard || style="width: 100px;vertical-align:top;text-align:center;"   | As listed in this ''Manual''
|-
| Mineral wool || style="width: 100px;vertical-align:top;text-align:center;"   | As listed in this ''Manual''
|}
<div id="INSUL_OVERLAY_APPLICATION"></div>

==Application==
===Guarantee Term Requirements===
====RoofStar 5-year and RoofStar 10-year Guarantee====
<ol>
<li>All ''projects'' intended to qualify for a '''''RoofStar 5-year''''' or '''''RoofStar 10-year Guarantee''''' shall comply with the requirements in this Part.
</li></ol>

====RoofStar 15-Year Guarantees====
<ol>
<li>All ''projects'' intended to qualify for a '''''RoofStar 15-year Guarantee''''' shall comply with the requirements in this Standard for a '''''RoofStar 5-year''''' or '''''RoofStar 10-year Guarantee''''', together with the following:
<ol>
<li>An insulation overlay must be installed in all insulated ''systems'', regardless of the insulation type.
<li>Insulation overlays must
<ol>
<li>be at least 6.4 mm (1/4”) thick, and
<li>possess a compressive strength of at least 690 kPa (100 psi).
</li></ol>
</li></ol>
</li></ol>

===All Systems===
====Alignment of Overlays====
<ol>
<li>See the Design requirements in Section 1 of this Part.
<li>{{hilite | Insulation overlays || 2021-June-30 }} 
<ol>
<li>{{hilite |  must be square and make firm, full contact with adjacent panels unless specified otherwise by the manufacturer|| 2021-June-30 }}, and
<li>{{hilite | must be offset at least 300 mm (12") from the joints of the insulation layer; a minus offset tolerance of 50 mm (2") maximum is permissible|| 2021-June-30 }}.
</ol></li>
<li>When multiple layers of an {{hilite | insulation|| 2021-June-30 }} overlay are specified, the joints between boards must be offset/staggered at least 300 mm (12") from adjacent layers and rows (See '''Figure 8.1'''. See also '''Part 7 INSULATION'''.
<br>
{| class="wikitable"; table style="background-color:white"; border="#A9A9A9;"
|+ '''Figure 8.1''' (Click to expand)
|-
| [[File:8.1 Insulation and Overlays.jpg| link=http://rpm.rcabc.org/images/9/9e/8.1_Insulation_and_Overlays.jpg |400 px]]
|}
</ol></li>

====Mechanical Securement====
<ol>
<li>When mechanically attaching insulation overlay boards, the insulation and overlay boards may be fastened together as one ''assembly''. 
<li>Unless otherwise indicated by the system requirements in a ''Tested Assembly'', follow the fastener patterns set out in '''Part 3 SECURING the ROOF ASSEMBLY'''.
<li>When a membrane-laminated overlay is mechanically fastened over insulation, fasteners and plates used in the field of each panel must be covered with torch-applied polyester or composite-reinforced membrane patches that extend past the edge of each plate at least 50 mm (2”).
</ol></li>

====Adhered Securement====
<ol>
<li>{{hilite | Adhered overlays must conform to the Design requirements in Section 1 of this Part|| 2022-June-17 }}.
<li>{{hilite | ''Roof system'' components adhered with two-component low-rise polyurethane foam must be|| 2021-June-30 }}
<ol>
<li>{{hilite | installed immediately in wet adhesive (before a surface skin develops), applied|| 2021-June-30 }} 
<ol>
<li>{{hilite | in parallel runs or in a Z-pattern, no more than 150 mm (6”) from any edge of the board and spaced no more than 300 mm (12”) apart|| 2021-June-30 }},
<li>{{hilite | to a clean, dry and contaminant-free surface|| 2021-June-30 }}, and
<li>{{hilite | in ribbon widths specified by the adhesive manufacturer or, in the absence of manufacturer requirements, 19 mm (3/4”) wide|| 2021-June-30 }}.
</ol></li>
<li>{{hilite | properly placed and weighted in wet adhesive until cured|| 2021-June-30 }}.
</ol></li>
<li>{{hilite | Hot bitumen used to adhere a ''roof assembly''|| 2021-June-30 }}
<ol>
<li>{{hilite | must be applied at minimum rates and temperatures based on the type of product, as published by the material manufacturer and in the '''RoofStar Guarantee Standards for Built-up Roof (BUR) Systems'''|| 2021-June-30 }}, and
<li>{{hilite | may be applied on slopes up to 1/2:12 (for steeper slopes, select a different method of securement)|| 2021-June-30 }}.
</ol></li>
</ol></li>
</ol></li>