View source for Template:Part 1 (Waterproofing Roofs - TPO)

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==References==
In this ''Manual'', all references to
<ol>
<li>the ''British Columbia Building Code'', municipal or regional building codes or regulations (collectively referred to as the “Code”), or other standards, presume the current edition that is in force.
<li>materials are assumed to be Accepted by the RGC, unless stated otherwise.
</li></ol>

==Definitions==
:;''Assembly'': means a ''system'' in combination with its supporting ''deck'' structure (adapted from ''ASTM D6630-08 Standard Guide for Low slope Insulated Roof membrane Assembly Performance''.
;:
:;''Contractor'': means the installer of a ''project''.  For the purpose of issuing a '''''RoofStar Guarantee''''', ''Contractor'' shall be read to mean an Active Member of the RCABC.
;:
:;''Design Authority'': means the individual or firm responsible for the issuance of ''Project'' specifications and details to which the ''Project'' will be bid and constructed.  When a ''Contractor'' designs a ''Project'', the ''Contractor'' is deemed to be the ''Design Authority''.
;:
:;{{hilite |''Finished {{hilite |waterproofing/water-shedding|| 2021-February-7 }} system''|| 2020-February-3 }}: {{hilite | means the top surface of a ''waterproofing system'' or ''water-shedding system'' that may include ballast or that supports ''overburden''|| 2021-February-7 }}.
;:
:;''Guarantor'': means the RGC '''''RoofStar Guarantee Program''''' that issues the '''''RoofStar Guarantee''''' ("''Guarantee''"); the two terms may be used interchangeably.
;:
:;{{hilite | ''Linear metal flashings''|| 2021-June-30 }}: {{hilite | are flashings cut and shaped from flat metal stock, to redirect water at roof perimeters and edges, and are used in valleys and drainage spillways|| 2021-June-30 }}.
;:
:;''Manual'': means the '''''Roofing Practices Manual'''''.
;:
:;''Project'': means the {{hilite | scope of work for which the ''Contractor'' is responsible|| 2022-February-5 }}.
;:
:;''System'': means the organization and securement of various interacting materials (apart from the supporting ''deck'' structure), designed and installed to prevent the transmission of water through the ''system'' into the conditioned space of a building (adapted from ''ASTM D6630-08 Standard Guide for Low slope Insulated Roof membrane Assembly Performance'').
;:
:;''Waterproofing system'': means a sheet membrane or liquid-applied ''system'' that, regardless of slope, excludes water from a building and therefore waterproofs it.  These systems are typically installed on slopes less than 1:4 (3” in 12”), on roofs or at grade level.
;:
:;''Water-shedding system'': means a ''roof system'' that, with sufficient slope, sheds water away from a structure but does not necessarily waterproof it.
;:

Refer to the [http://rpm.rcabc.org/index.php?title=Glossary '''Glossary'''] for further definitions of key terms used in this ''Manual''.

==Design==
===RoofStar 15-Year Guarantee===
<ol>
<li>To qualify for a '''''RoofStar 15-year (Waterproofing Roofs) Guarantee''''', the following standards apply:
<ol>
<li>Each ''project'' must be designed and constructed in compliance with both the '''''RoofStar Guarantee Standards''''', together with the membrane manufacturer’s available 20-year System Warranty standards.
<li>Where enhanced roof system securement is required by the manufacturer, which may exceed the securement required in a ''Tested Assembly'', an ''Assembly with Proven Past Performance'' or a custom-engineered securement, the ''project'' must comply with the higher securement requirements.
<li>{{hilite | In addition to the above, other requirements in this Standard apply, which can be summarized (without limitation) as follows || 2022-February-5 }}:
<ol>
<li>{{hilite | Roofs must be designed for adequate access to facilitate maintenance || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#Accessibility_for_Maintenance | 1.3.3]]).
<li>{{hilite | Materials left in place for partial roof system replacement must be scanned for moisture || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#Membrane_Replacement | 1.4.2.2]]).
<li>{{hilite | All roofs (new construction and replacement roofing) must be built with a minimum slope of 2% (1:50) || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#New_Construction_2 | 2.2.2]] and [[RoofStar Guarantee Standard for TPO Membrane Systems#Replacement_Roofing | 2.2.3]]).
<li>{{hilite | All replacement roofing must utilize crickets to enhance drainage around curbs and sleepers || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#Replacement_Roofing | 2.2.3]]).
<li>{{hilite | ''Curbs'' and sleepers wider/longer than 1200 mm (48") must incorporate crickets to improve drainage || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#RoofStar_15-Year_Guarantee_4 | 7.1.2.1]]).
<li>{{hilite | An insulation overlay is required on all ''Conventionally Insulated Roof Systems'' || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#RoofStar_15-Year_Guarantee_5 | 8.1.1.1]]).
<li>{{hilite | Only certain membranes will qualify for a '''''RoofStar 15-year Guarantee''''' || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#Materials_8 |9.2]]).
<li>{{hilite | All drains and overflows require clamping rings, and overflows are required for each roof area || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#RoofStar_15-Year_Guarantee_12 | 11.1.2.1]]).
<li>{{hilite | Enhanced penetration flashing requirements || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#RoofStar_15-Year_Guarantee_12 | 11.1.3.1]]).
<li>{{hilite | ''Linear metal flashings'' must be fabricated from 24-gauge material || 2022-February-5 }} ([[RoofStar Guarantee Standard for TPO Membrane Systems#RoofStar_15-Year_Guarantee_15 | 13.1.2.1]]).
</li></ol>
</li></ol>
</li></ol>

===System Types===
<span class="principles">Designing a good roof begins with the end in mind and an answer to the essential question, “What purpose will the roof serve?”  For example, the roof may</span>
*<span class="principles">simply weatherproof the building interior</span>.
*<span class="principles">provide a location for building equipment and services</span>.
*<span class="principles">support liveable spaces</span>.
<br>
<span class="principles">Each of these functions may limit the choice of membrane assembly</span>.
<br><br>
<span class="principles">There are four principal waterproofing assemblies used on roofs:</span>
<ol>
<li><span class="principles">''Uninsulated Systems''(insulation may be installed beneath the deck)</span>.
<li><span class="principles">''Conventionally Insulated Systems'' (sometimes referred to as ''Compact Roofs'')</span>.
<li><span class="principles">''Protected Membrane Roof Systems'' (also referred to as “inverted”)</span>.
<li><span class="principles">''Modified Protected Membrane Roof Systems''</span>.
</li></ol>
<br>
<span class="principles">Of course, sometimes the roof ''deck'' influences these choices.  Regardless of the ''Design Authority’s'' starting point, knowing where you are going is the beginning of a successful design</span>.

{{hilite | Regardless of the ''system'' type, the ''Finished waterproofing system'' is defined by whatever is placed on the membrane, which may be insulation, ballast, pavers or overburden.  These materials will displace water and therefore affect the height of membrane flashing needed to prevent water ingress.  The definition of ''Finished waterproofing system'' is illustrated below in '''Figures 1.3.2-1''' and '''1.3.2-2'''.  See also '''1.2 Definitions'''|| 2021-February-7 }}.

<div class="col-md-12">
<div class="col-md-6">
{| class="wikitable"; table style="background-color:white"; border="#A9A9A9;"
|+{{hilite | '''Figure 1.3.2-1''' (Conventionally Insulated Waterproofing System)(Click to expand) || 2021-February-7 }}
|-
| [[File:Waterproofing Figure 1.3.2-1.jpg|link=http://rpm.rcabc.org/images/d/d4/Waterproofing_Figure_1.3.2-1.jpg | 400 px]]
|}
</div>
<div class="col-md-6">
{| class="wikitable"; table style="background-color:white"; border="#A9A9A9;"
|+{{hilite | '''Figure 1.3.2-2''' (Protected Membrane Roof System)(Click to expand) || 2021-February-7 }}
|-
| [[File:Waterproofing Figure 1.3.2-2.jpg|link=http://rpm.rcabc.org/images/5/51/Waterproofing_Figure_1.3.2-2.jpg | 400 px]]
|}
</div>
</div>

<div id="SBSCONVENTIONAL"></div>
====<big>Conventionally Insulated Waterproofing Systems</big>====
<ol>
<li><span class="reference">In a ''Conventionally Insulated Waterproofing System'', the membrane is the final layer, exposed to the weather.  It protects the other roofing components, including insulation, from exposure to water, wind and other weather conditions</span>.  ''Conventionally Insulated Waterproofing System'' are classified in this ''Manual'' by three different methods of attachment (securement) to the roof ''deck'':
<ol>
<li>'''Mechanically Attached Roof Systems (MARS)'''
<li>'''Partially Adhered Roof Systems (PARS)'''
<li>'''Adhesive Applied Roof Systems (AARS)'''
</li></ol>
<br>More about these three ''systems'' is offered in '''Part 3 SECURING the ROOF ASSEMBLY'''.
</li></ol>

====<big>Protected and Modified Protected Membrane Roof Assemblies</big>====
NOTE: See more information on [http://rpm.rcabc.org/index.php?title=Protected_and_Modified_Protected_Roof_Systems '''Protected and Modified Protected Roof Systems'''] in '''Division B: Essential Elements'''. 
<ol>
<li><span class="reference">In a ''Protected Membrane Roof System'' (or ''Protected Membrane Roof Assembly'', also called ''PMRA'') the membrane is applied directly to the ''supporting deck'' structure or the ''deck'' overlay (as required and/or specified), and protected from both the elements and damage with insulation and an overburden.  In this way, the membrane functions both to waterproof the roof and control air or vapour.</span>   Only RoofStar-accepted extruded expanded polystyrene (XPS, conforming to ''CAN / CGSB-51.20-M87'', Type 4) is acceptable for a ''PMRA''.  <span class="reference">XPS is water-resistant (i.e. resistance to water absorption, moisture transfer, and capillary action), freeze-thaw cycling resistant, and possesses a high compressive strength.</span>  <span class="principles">If a drainage layer is specified, it is typically installed between the membrane and insulation.  An additional drainage layer may be installed above the insulation, together with a filter fabric mat and ballast or ''overburden''.  These three components - a drainage layer, filter fabric and ballast - promote controlled drainage, resist infiltration of contaminants, resist the lifting forces of wind, and counteract the natural buoyancy of the insulation</span>.
<li>''PMRAs'' are the required roof assembly design for certain types of ''overburden''.  See '''14.1.2 Design''' for '''''RoofStar Guarantee Standards'''''.
<li><span class="reference">A ''Modified Protected Membrane Roof System'' (or ''Modified Protected Membrane Roof Assembly'', also called ''MPMRA'') is similar to a ''PMRA'' except that that insulation is installed <u>both below and above</u> the membrane. This may offer cost savings as only the top layer of insulation requires ballast and the bottom layer (mechanically fastened or adhered) need not be extruded expanded polystyrene and may be tapered to provide slope.</span>  <span class="principles">As a '''general''' rule, two-thirds or more of the total thermal resistance (RSI or R value) should be above the membrane, but in '''all cases''' the ''Design Authority'' should perform the required psychrometric calculations before designing a ''roof system''</span>.
</li></ol>

===Accessibility for Maintenance===
====RoofStar 15-Year Guarantee====
<ol>
<li>On all "new construction" ''Projects'', where external access is not provided, all roofs with a field elevation greater than 7500 mm (25’) above grade must incorporate safe, appropriate access to the roof, for example by incorporating stairs and a doorway or a properly located roof hatch.   <span class="recommended">These requirements are recommended for existing buildings to facilitate maintenance and ongoing performance reviews</span>.
</li></ol>

====All Projects====
While the '''''RoofStar Guarantee Standards''''' pertain to the design and construction of a leak-free roof, accessible design is still critical since a roof must be regularly maintained.  Therefore, while the following list is not exhaustive, the ''Design Authority'' is urged to consider these guiding principles when designing a ''roof Project''.
<ol>
<li><div class="recommended">All roofs with a field elevation greater than 7500 mm (25’) above grade should incorporate access to the roof by stairs and a doorway or with a properly located roof hatch.</span>
<li><span class="principles">Any hatch, ladder or mechanical unit should be located a sufficient distance away from the roof edge (setback zone) so that other fall protection measures are not required by those using or accessing this equipment.  When it is not possible to situate a hatch, ladder or mechanical unit outside the setback zone, guard rails should be designed for the roof edge to provide additional fall protection for those using or accessing such equipment</span>.
<li><span class="principles">Each roof should be designed to provide safe access for maintenance of roof drains, corners or mechanical equipment, where the roof is at least 3 m (10’) above the surface of the ground, or where a hazard to a person exists, should a fall be possible.  This principle also applies to roof areas intended for regular occupancy.  Therefore, provide fall protection in compliance with the Code having jurisdiction, and with the ''Workers Compensation Act Regulations'', by designing appropriately located</span></li>
<ol>
<li><span class="principles">tall parapets</span>.
<li><span class="principles">guardrails</span>.
<li><span class="principles">tie-off anchors</span>.</li></ol>
</li></ol>

===Waterproofing Integrity Scans and Electronic Leak Detection===
<span class="reference">An integrity scan is performed after the installation of the roof ''waterproofing system'', before any ''overburden'', equipment or amenity space is installed on top of it. An integrity scan typically uses low-voltage electrical current to detect even the smallest breaches in the roof membrane, but some waterproofing materials may require the use of other technologies to verify the roof system’s integrity.</span>  <span class="principles">Therefore, ''Design Authority'' should specify the appropriate technology, keeping in mind the limitations of each scan and detection methodology, and of the membranes that are specified.</span>

<span class="reference">Electronic Leak Detection (ELD) utilizes low-voltage electrical current, typically conducted through wires installed in a grid pattern.  ELD technologies are used in response to a leak, to isolate its location in order to minimize investigation time and material removal. This can benefit a building owner who will have to bear the costs of demolition or overburden removal when the standard limits of coverage afforded by the</span> '''''RoofStar Guarantee''''' <span class="reference">are exceeded by the ''Project'' design and construction.  ELD technologies may be passive (installed but not monitored) or actively monitored (by the installer, through real-time data collection)</span>.
<ol>
<li><span class="recommended">Flood testing (as an alternative to an integrity scan) is not recommended</span>. When flood testing is specified, testing shall be conducted prior to installation of insulation and roof coverings, and must be performed following the methodologies in ''ASTM D5957''.
<li>Neither an integrity scan nor an Electronic Leak Detection (ELD) system are considered Accepted Materials, but firms that provide these services are nevertheless specifically recognized and approved by the '''''RoofStar Guarantee Program'''''.
<li>An integrity scan is required for some ''projects'' (see '''1.6 RoofStar Guarantee: Coverage and Limitations'''), <span class="recommended">but is nevertheless strongly recommended before the completed ''roof assembly'' is covered with ''overburden'', equipment or living (amenity) spaces</span> (see '''14.1.2.1''').
<li>Electronic Leak Detection is required for all grade-level ''waterproofing systems'', and while it is optional for roof ''waterproofing systems'', <span class="recommended">ELD is strongly recommended</span>
<ol>
<li><span class="recommended">for ''projects'' where multiple trades will have access to a roof that is under construction and completed, in order to identify breaches in the waterproofing membrane in a timely way and avoid future costly delays</span>.
<li><span class="recommended">when the ''roof assembly'' protects a sensitive occupied space (i.e. data centres, hospitals, critical infrastructure)</span>.
<li><span class="recommended">when the roof supports any type of ''overburden'', equipment or living (amenity) space</span>.
</li></ol>
<li> <span class="principles">When Electronic Leak Detection is specified, it should provide detection capabilities for all waterproofed surfaces, and should extend at least 50 mm (2") vertically from the water plane at</span>
<ol>
<li> <span class="principles">all transitions</span>.
<li> <span class="principles">any point along the entire deck perimeter</span>.
<li> <span class="principles">protrusions</span>.
</li></ol>
</li></ol>

===Hot Works: {{hilite | Design || 2021-February-7 }}===
<span class="reference">When any portion of a ''waterproofing system'' is installed with heat, the work is classified as Hot Works.  Some tools used in the course of Hot Works can ignite combustible materials, and some building environments are more sensitive to fire than others, such as a building containing, or close to, flammable liquids. Hot Works may occur during</span>
*<span class="reference">tear off (sparks)</span>.
*<span class="reference">deck preparation (drying wet surfaces)</span>.
*<span class="reference">cold temperatures (warming materials or surfaces)</span>.
*<span class="reference">equipment use (sparks within electrical tools, or from cutting, drilling or grinding metal, concrete, stone or other hard surface products)</span>.
<ol>
<li><span class="recommended">The ''Design Authority'' may specify that the ''Contractor'' must maintain compliance with the RCABC Hot Works Program and consequently manage the Hot Works conducted on site</span>.
<li>When the ''Project'' involves Hot Works, the ''Design Authority'' must either
<ol>
<li>pre-approve alternate applications already written within the ''Manual'' when the specified application is deemed to be fire-sensitive by the ''Contractor'' as part of the risk assessment process.
<li>provide alternate material and application requirements in the specification for fire-sensitive locations on the ''project''.
</li></ol>
</li></ol>
<br>
See also '''1.4.3 Hot Works{{hilite |: Contractor Requirements|| 2021-February-7 }}'''.

==={{hilite | Variances || 2021-June-30 }}===
{{hilite | When a design is unable to conform to the Standard, the ''Design Authority'' may apply to the RGC for a written Variance.  Application must be made in writing (email correspondence is common), and the request must|| 2021-June-30 }}
<ol>
<li>{{hilite | identify the ''project'' name, its civic address and the applicable '''''RoofStar Guarantee''''' number (if already initiated)|| 2021-June-30 }}.
<li>{{hilite | articulate the nature of the design problem|| 2021-June-30 }}.
<li>{{hilite | cite the '''''RoofStar Guarantee''''' standard reference to which the Variance will apply|| 2021-June-30 }}.
<li>{{hilite | provide design drawings (and photographs, if available) as supporting information|| 2021-June-30 }}.
</li></ol>
{{hilite | We may ask for more information in order to fully consider a request for a Variance and will issue a completed Variance only to the ''Design Authority'' for distribution to the ''Contractor''|| 2021-June-30 }}.

{{hilite | A Variance may be unrestricted in its scope, or it may include one or more conditions that will affect the design and construction of the ''water-shedding system'' or ''waterproofing system'', in order to accommodate the varied standard.  Occasionally, a Variance may also restrict coverage offered by the '''''RoofStar Guarantee'''''|| 2021-June-30 }}.

{{hilite | Variances are issued only for the specific issue on the ''project'' identified in the written request, and do not constitute general permission to depart from the published requirements in this Standard, for any aspect of the same ''project'' or for future ''projects'', designed or constructed by any other firm|| 2021-June-30 }}.

==Scope==
<ol>
<li>{{hilite | The '''''Guarantee Standards''''', Guiding Principles, Recommendations and Reference Materials in this Standard pertain to both new roofing construction and replacement roofing, unless explicitly stated otherwise|| 2020-July-3 }}.
</li></ol>

===New Construction===
<ol>
<li>{{hilite | New roof construction must utilize only newly manufactured materials, and may not incorporate recycled products, unless with the expressed, written consent of the '''''Guarantor'''''|| 2020-July-3 }}.
</li></ol>

===Replacement Roofing and Additions===
As a roof ages, is neglected or is damaged, it may lose its ability to perform reliably and effectively, necessitating replacement.  Replacement roofing, also referred to as "re-roofing," whether made in whole or in part, should be undertaken with the Quality Assurance and Quality Control provided for under the '''''RoofStar Guarantee Program'''''.  Regardless of the approach to replacement roofing, the existing deck structure must meet the pullout resistance rating for mechanical fasteners and must be capable of supporting all dead and live loads.  Furthermore, the deck must be capable of supporting any additional dead loads of the new roof system.

Three types of replacement roofing are contemplated and permitted (with varying degrees of limitations and conditions) under the '''''RoofStar Guarantee Program''''':
*'''System replacement''' - removal and replacement of all ''roof system'' components, except for the supporting deck structure.
*'''Membrane replacement''' – removal and replacement of the roof membrane, while retaining existing ''roof system'' components (i.e. insulation, ballast).
*'''Recovering''' - installation of a new membrane over an existing membrane, while retaining some or all of the other ''roof system'' materials (NOTE: Recovering is permitted only with a written Variance issued by the '''''Guarantor''''').
<br>
Qualifying and construction conditions and limitations for each of these replacement options are described below.  Other conditions and limitation may be determined by the '''''Guarantor''''' subject to the nature and specifications of the replacement roofing ''project''.

====<big>System Replacement</big>====
<ol>
<li>{{hilite | ''Roof system'' replacement means the complete removal and replacement of all ''roof system'' and metal flashing materials, exclusive of the air or vapour control layers (see '''1.4.2.1''' ('''2''') below).  Only new replacement materials are permissible.  The design of the replacement ''roof system'', and the installation of new materials, must conform to the '''''RoofStar Guarantee Standards''''' for new roof construction, unless expressly varied elsewhere in this Standard (see, for example, alternate slope requirements and recommendations in '''2.2.3 Replacement Roofing''') || 2021-June-30 }}.
<li>Subject to the requirements in '''6 AIR and VAPOUR CONTROLS''', the decision to reuse and repair an existing air or vapour control layer remains the responsibility of the ''Design Authority''.
<li>Subject to the requirements in '''6 AIR and VAPOUR CONTROLS''', the decision to reuse and repair an existing air or vapour control layer remains the responsibility of the ''Design Authority''.
<li>''Roof system'' replacement ''projects'' are eligible to qualify for a '''''RoofStar 5-year Guarantee''''', '''''RoofStar 10-year Guarantee''''', or '''''RoofStar 15-year Guarantee'''''.
</li></ol>

====<big>Membrane Replacement</big>====
=====<big>RoofStar 15-Year Guarantee</big>=====
<ol>
<li>In addition to the '''General Requirements''' for Membrane Replacement outlined below, a ''project'' designed to qualify for a '''''RoofStar 15-year Guarantee''''' must
<ol>
<li>be supported by the following, submitted in report form to the '''''Guarantor''''' for review and consideration prior to tender:
<ol>
<li>moisture survey scan performed by a qualified person.
<li>at least three (3) cut tests for roof areas up to 20,000 sf (200 squares), or one (1) cut test for every 2000 sf (20 squares), whichever is more.
<li>one (1) cut test for every 3000 sf (30 squares) of roof area that exceeds the first 20,000 sf (200 squares).
<li>one (1) cut test for each small roof area measuring no more than 200 sf (2 squares).
</li></ol>
<li>incorporate new insulation overlays in keeping with the requirements published in '''Part 8 INSULATION OVERLAYS'''.
</li></ol>
</li></ol>

=====<big>General Requirements</big>=====
Membrane replacement is a partial ''roof system'' replacement, limited to the membrane or materials adhered to the membrane.  A written Variance is not needed for this type of ''project'', but for membrane replacement to qualify for a '''''RoofStar Guarantee''''',
<ol>
<li>the ''Design Authority'' must be certain the existing ''roof system'' is properly secured to the existing deck structure (see '''Part 3 SECURING the ROOF ASSEMBLY''').
<li>the existing ''roof system'' must be demonstrably dry and free of any wet materials (wet materials must be replaced, in order to qualify for a '''''RoofStar Guarantee''''').
<li>the existing field membrane must be removed and replaced with a new insulation overlay board and a new membrane.
<li>existing membrane flashing must be removed and replaced with new materials.
<li>the design must comply with the '''''RoofStar Guarantee Standards''''' for new roof construction.
</li></ol>

====<big>Recovering</big>====
Recovering - installing a new membrane over an existing membrane - is permitted in certain circumstances for a '''''RoofStar 5-year Guarantee''''' or '''''RoofStar 10-year Guarantee''''', <span class="recommended">though it is not a recommended practice and will limit the scope of coverage for the '''''RoofStar Guarantee'''''</span>. Recovering does not qualify for a '''''RoofStar 15-year Guarantee'''''.  

Qualifying for a '''''RoofStar Guarantee''''' is subject to the General Conditions and Limitations listed below and is permitted only with a written Variance issued by the '''''Guarantor'''''.  A '''''RoofStar Guarantee''''' issued for a recovered roof is limited strictly to the value of new roof system materials; existing materials that remain in place beneath new materials do not qualify for coverage under the '''''RoofStar Guarantee'''''. 

=====<big>Recovering: Project Qualifications</big>=====
Any Variance permitting roof recovering must be applied for in writing by the ''Design Authority'', addressed to the '''''RoofStar Guarantee Program''''' prior to the tendering of documents.  To qualify for a Variance, the following conditions must be met and confirmed in the written application:
<ol>
<li>The new ''roof system'' must be properly secured to the existing deck structure (see '''Part 3 SECURING the ROOF ASSEMBLY''').
<li>The existing ''roof system'' must be distinct and physically separate from other roof areas.
<li>The request for a Variance must identify the type of ''roof system'' - ''Conventionally Insulated'', ''Protected Membrane Roof System'' or ''Modified Protected Membrane Roof System''.
<li><u>''Conventionally Insulated Systems'' only</u>: The existing ''roof system'' must be independently surveyed by qualified professionals using calibrated moisture detection equipment and cut tests, and the resulting survey shall be formally documented for review by the '''''Guarantor'''''.  The following requirements for cut tests apply, based on roof area.  All cut tests shall be independently documented for review by the '''''Guarantor''''':  
<ol>
<li>At least three (3) cut tests for roof areas up to 20,000 sf (200 squares), or one (1) cut test for every 2000 sf (20 squares), whichever is more.
<li>One (1) cut test for every 3000 sf (30 squares) of roof area that exceeds the first 20,000 sf (200 squares).
<li>One (1) cut test for each small roof area measuring no more than 200 sf (2 squares).
<li>Where the roof has been constructed with a structurally sloped ''deck'', at least 50% of the required cut tests shall sample roof areas in or near valleys, and areas; samples shall also be taken near roof drains.
</li></ol>  
<li>Where the roof has been constructed with a structurally flat ''deck'', samples shall be taken near roof drains and in a random pattern across the roof.  
<li>All cut tests for existing SBS-modified membrane ''roof systems'' shall be performed to ''ASTM D7636/D7636M, 11 Standard Practice for Sampling and Analysis of Modified Bitumen Roof Systems''.
<li>Existing ''Conventionally Insulated Roof Systems'' constructed with expanded polystyrene insulation (EPS) may qualify for a '''''RoofStar Guarantee''''', subject to the General Conditions and Limitations below.
</li></ol>

=====<big>Recovering: General Conditions and Limitations</big>=====
In addition to the '''''RoofStar Guarantee Standards''''' found in this ''Manual'', the following additional requirements and conditions apply:
<ol>
<li>All wet material identified by either the independent moisture detection survey or through cut tests shall be
<ol>
<li>specified for removal.
<li>removed in the course of construction.
</li></ol>
<li>The existing membrane on a ''Conventionally Insulated System'' must be cut through 
<ol>
<li>in a grid pattern measuring no larger than 6m x 6m (approximately 20' x 20').
<li>around the perimeter of the roof area, no more than 0.2 m (8") from the edge.
<li>A grid-cut field membrane must be overlaid with a mechanically attached insulation overlay board acceptable to the '''''Guarantor'''''; notwithstanding this requirement, only non-organic and moisture-resistant overlay boards may be used in the ''Project''.
<li>When expanded polystyrene insulation (EPS) is present in an existing ''roof system'', the existing membrane must be overlaid with at least one layer of 50 mm (2”) mineral wool or polyisocyanurate insulation, in combination with a RoofStar-accepted insulation overlay board (as required).
<li>New membranes must be properly secured to the underlying ''roof assembly''.
<li>Only new strip-in flashings for roof penetrations are acceptable for a '''''RoofStar Guarantee'''''; reusing existing flashings is not permitted.
<li>Only new roof drains are acceptable for a '''''RoofStar Guarantee''''', and under no circumstances shall existing roof drains be reused.  Cast-iron roof drains in usable condition are exempted from this Standard (see '''11.1.2.2(3)''').
<li>Only new ''linear metal flashings'' are acceptable for installation at perimeters or at membrane terminations, and under no circumstances shall existing ''linear metal flashings'' be reused.
</li></ol>
</li></ol>

====<big>Tie-ins and Additions to Existing Roofing</big>====
<ol>
<li>Where a new roof adjoins and ties into an existing roof, the two areas must be isolated and separated by a curb joint securely attached to the structure and waterproofed in keeping with the requirements in '''2.5 Control Joints''' and '''Part 10 PERIMETERS and WALLS'''. 
<li>If ''project'' conditions do not allow for a curb joint, the ''Design Authority'' must obtain a written Variance from the '''''Guarantor''''' that permits the elimination of curb joints.  Application for a Variance must include design specifications and construction details showing a positive water cut-off that fully isolates the existing roof from the new roof.  In the absence of a curb joint, the new ''roof system'' must be easily distinguishable from the existing roof system.
</li>
</ol>

===Hot Works: {{hilite | Contractor Requirements || 2021-February-7 }}===
<ol>
<li>The ''Contractor'' must maintain the requirements of the RCABC Hot Works Program. This includes the following, without limitation:
<ol>
<li>'''Insurance Coverage''' – limits carried on the ''Contractor’s'' policy must equal or exceed the minimum requirements set by RCABC, and coverage must be unhindered by warranties that limit or exclude coverage when Hot Works is required.
<li>'''Education and training''' – workers who perform Hot Works must be trained by the ''Contractor'' and kept current with acceptable methods.
<li>'''British Columbia Fire Code''' – a Fire Safety Plan, preventative methods or alternative work procedures, fire watches, and the use and placement of equipment at the ''project'' site must comply with the BC Fire Code requirements for Hot Work.
<li>'''Fire Safety Plan''' – the ''Contractor'' must assess the hazards to property and persons and produce a written Fire Safety Plan prior to the start of work.  The Fire Safety Plan must be kept on the ''Project'' site and must be kept current until the ''project'' is completed.
<li>'''RoofStar Guarantee Standards''' – the ''Contractor'' must adhere to the '''''RoofStar Guarantee Standards''''' at each juncture where the interface of different membranes applications constitutes part of the Fire Safety Plan.
<li>'''Fire Watch''' – the ''Contractor'' must, as part of the Fire Safety Plan, conduct a fire watch
<ol>
<li>that complies with the ''British Columbia Fire Code''.
<li>assigned to competent, trained personnel using suitable equipment, including the use of a hand-held infrared thermometer.
<li>documented in a written fire watch log.
</li></ol>
<li>'''Hot Works Notification''' – notify the ''project'' authority or the AHJ, as and when required, that Hot Works will be performed.
</li></ol>
</li></ol>

==Workmanship==
While integrity and functionality of a new roof or grade-level waterproofing is the foundation of a '''''RoofStar Guarantee''''', it is no less important to ensure that the finished ''project'' exhibits excellent workmanship.  {{hilite | Therefore, the following Standards apply|| 2021-February-7 }}:
<ol>
<li>{{hilite | The ''Contractor'' must take reasonable measures to protect the ''project'' from damage by the weather, during and at the completion of {{hilite |the ''project''||2022-February-5 }}.  Open penetrations and flashings must be temporarily sealed off from the weather, even when other trades are responsible to make a permanent seal or install overlapping materials.  See also '''4.2 General''' || 2021-February-7 }}.
</li></ol>

===Contractor Qualifications===
<ol>
<li>Supervision and installation of a RoofStar-guaranteed roof ''waterproofing system'' may be conducted only by established employees of the ''Contractor'', and every ''project'' must be supervised by a Journeyperson employee who holds a valid ticket.  In keeping with RCABC Membership policy, a Journeyperson may supervise a maximum of three (3) apprentices and/or three (3) labourers (ref. RCABC Policy A-248, Rev. 5 April 2019).
</li></ol>

==RoofStar Guarantee: Coverage and Limitations==
{{Template:Section 1.6 (All Standards)}}