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MB Section 5: Insulation

MB-5.1 General

.1

Primary insulation is the system component that provides the major portion of the thermal performance of the roofing system. The location of the primary insulation can vary, depending on the roofing system design type.

.2

For ARCA Warranty Ltd. acceptance, insulation products must be tested by a certified testing agency approved by the Standards Council of Canada for a Canadian Construction Materials Centre (CCMC) evaluation listing to verify compliance to an existing standard such as the Underwriters’ Laboratories of Canada (ULC) insulation standard. Third party certified thermal insulation products are accepted by specific manufacturer and product name and are not accepted generically for inclusion under the Warranty Certificate Program.

.3

To eliminate confusion during the tendering process, it is recommended that the design authority specify roof insulation by the type and thickness of insulation to be used. Specifying insulation by thermal resistance values may lead to confusion during the construction process as insulation thickness affects the design heights of other building components, such as perimeters, curbs and junctions.

.4

Insulation shall be protected during shipping and site storage to prevent moisture infiltration and damage. No insulation material, either primary or secondary, is to be installed when its moisture content exceeds the manufacturer’s stated equilibrium moisture content. Wet or damp insulation must be removed. Surface moisture should be allowed to dry.

.5

When specifying plastic foam insulation, the design authority must ensure compliance with Alberta Building Standards relative to the use of thermal barriers, as this falls outside the expertise of the roofing contractor.

.6

Only new insulation shall be installed in new conventional insulated roofing assemblies.
Added

2017-11

MB-5.2 Insulation Blocking for Sloped Decks

.1

To prevent primary membrane movement or insulation displacement, when deck slopes exceed 1:8 (1.5”/ ft.), continuous wood nailers or insulation blocking shall be mechanically fastened to the decking. The design of the insulation blocking system is the responsibility of the design authority and is not covered by the Warranty Certificate.

.2

When insulation blocking is required, all roofing system components shall be uniformly adhered to each other and to their supporting substrate. Multiple layers of primary insulation require multiple layers of insulation blocking. The upper nailers shall be oriented perpendicular to the direction of the primary membrane.

.3

The size and spacing of the blocking shall match the primary insulation board dimensions and shall provide for the mechanical fastening of the primary membrane. The maximum spacing permitted between the blocking shall be determined by the membrane manufacturer. The top surface of the primary insulation shall be flush with the top surface of the blocking.
Revised

2010-06

.4

The secondary insulation shall be adhered to the primary insulation and shall be mechanically fastened to the blocking.

MB-5.3 Primary Insulation

.1

The primary insulation shall be uniformly adhered to the vapour retarder in a full application of hot bitumen, with an approved adhesive or mechanically fastened through the vapour retarder to the structural deck.

.2

Primary insulation boards shall be tightly butted together. Gaps at board joints greater than 6.4mm (1/4”) in width shall be filled with insulation. Where a single layer of primary insulation is specified the board joints may be aligned.

.3

When multi-layers of primary insulation are specified, offset board joints by a minimum distance of 150mm (6”) from the joints of the preceding insulation layer.

.4

For proper adhesion when primary insulation is adhered with adhesive or hot bitumen restrict board size to maximum 1200mm x 1200mm (4' x 4') dimensions.

.5

For mechanically fastened modified bitumen membranes applied over accepted polyisocyanurate primary insulation, without secondary insulation or a cover board, the top layer of insulation boards shall be pre-secured to the structural decking using the membrane manufacturer’s approved insulation screws and plates placed 300mm (12”) from the corners of each insulation board.
Revised

2012-03

.6

To qualify for an ARCA 15 Year Warranty Certificate, each roof assembly shall consist of a minimum of two layers of primary insulation with a minimum thickness of 38mm (1 1⁄2”) for each layer. The first layer of insulation shall be mechanically fastened to the structural decking. Additional layers of insulation shall be either mechanically fastened or adhered using an ARCA approved adhesive.
Added

2016-08

.7

To qualify for an ARCA 15 Year Warranty Certificate, the top layer of insulation shall be a minimum 38mm (1 1⁄2”) ARCA approved polyisocyanurate insulation meeting CAN/ULC S-704 Type 2, Class 3.
Added

2016-08

MB-5.4 Secondary Insulation

.1

The primary insulation shall be covered with a minimum 12.7mm (1/2”) thick layer of coated fiberboard, perlite secondary insulation, or stone wool insulation. The secondary insulation provides a preferred substrate for the adhesion of the primary membrane as well as provides some thermal resistance.
Revised

2012-03

.2

The secondary insulation shall be uniformly adhered to the primary insulation in a full mopping of bitumen, an adhesive approved by the primary membrane manufacturer or mechanically fastened to the structural deck.

.3

Secondary insulation joints shall be staggered and offset a minimum distance of 150mm (6”) from the joints of the underlying primary insulation.

.4

The top surface of standard fiberboard or stone wool insulation shall be manufactured with an asphalt coating for hot applied membranes. Wax or asphalt impregnated fiberboard need not be asphalt coated.
Revised

2012-03

.5

When polystyrene insulation forms the primary insulation layer, the secondary insulation shall be comprised of a single layer of 25mm (1”) thick shiplap edged or two (2) layers of 12.7mm (1/2”) thick butt edged impregnated/coated fiberboard or perlite roof insulation. Each secondary insulation layer shall be adhered with hot bitumen using the “mop and flop” back coating application method.

.6

For proper adhesion when using hot bitumen, the secondary insulation boards shall not exceed 1200mm x 2400mm (4' x 8') in size.

.7

Secondary insulation boards exceeding 1200mm x 2400mm (4' x 8') in size shall be mechanically fastened to the decking.

MB-5.5 Asphalt Core Boards

.1

Asphalt core board may be substituted for the secondary insulation layer over selected primary roof insulation when its application is approved by the primary membrane manufacturer.

.2

Polyisocyanurate roof insulation may be covered with a single layer of minimum 3.2mm (1/8”) thick accepted asphalt core board adhered with hot bitumen, a membrane manufacturer’s approved polyurethane foam insulation adhesive or mechanically attached to the structural decking using the manufacturer’s accepted roof insulation screws and metal plates.

.3

When approved by the membrane manufacturer for application over other accepted primary roof insulation, other than polyisocyanuarate roof insulation, two (2) layers of asphalt core board with joints offset a minimum distance of 150mm (6”) from the underlying core board and primary insulation layer joints shall be mechanically fastened to the structural decking or adhered with the membrane manufacturer’s accepted polyurethane foam insulation adhesive.
Revised

2010-12

MB-5.6 Fiberglass Faced Gypsum Roof Boards

.1

Minimum 6.4mm (1/4”) thick fiberglass faced gypsum roof board may be substituted for the secondary insulation layer for primary membrane attachment when approved by the membrane manufacturer. Paper-faced gypsum board is not permitted for W.C. issuance.

.2

Fiberglass faced gypsum roof board surface may be coated or uncoated. For proper membrane adhesion confirm priming requirements with the primary membrane manufacturer.

.3

Gypsum roof boards may be adhered to accepted substrates with membrane manufacturer’s approved insulation adhesive, hot bitumen, or mechanically attached to the roof decking following the membrane manufacturer’s written securement requirements. Attachment in a full mopping of hot bitumen is permitted only over faced insulations that are not heat sensitive.

.4

When torching membranes directly to glass faced gypsum board, direct the majority of torch flame towards the modified bitumen rolls rather than the surface of the gypsum roof board.
Revised

2016-06

.5

Gypsum board joints shall be supported and staggered a minimum distance of 150mm (6”) from the joints of the underlying substrate or insulation. When torching over heat sensitive substrates or insulation, all joints must be covered with 150mm (6”) 1.5mm (60mil) self-adhesive fire tape.
Revised

2016-06

.6

Do not leave gypsum roof board exposed to the weather for extended periods of time. At all times protect from moisture accumulation and mechanical damage. Keep the gypsum roof board dry prior to, during and after application. Apply only as many boards as can be waterproofed within the same work day.

MB-5.7 High Density Polyisocyanurate Cover Boards

.1

For mechanically fastened SBS modified bitumen membrane systems, a mechanically fastened 12.7mm thick high density (HD) polyisocyanurate roof insulation cover board may be substituted for the secondary insulation over accepted primary roof insulation when approved by the membrane manufacturer.

.2

Board joints shall be supported and staggered a minimum distance of 150mm (6") from the joints of the underlying substrate of insulation.

MB-5.8 Accepted Roofing Insulation

MB-5.8.1 Primary Insulation

.1

Each listed insulation manufacturer has confirmed third party product certification by an accredited independent testing agency by submission of a C.C.M.C. evaluation listing or equivalent, in accordance with the ARCA Warranty Ltd. insulation acceptance criteria.

.2

The design authority shall obtain long term thermal resistance (LTTR) values from the insulation manufacturer and shall specify primary insulation by thickness.
  1. Polyisocyanurate Roof Insulation

    • Atlas Roofing Corporation

      • AC Foam-11
    • Firestone Building Products Canada

      • ISO 95+
    • IKO Industries Ltd.

      • IKOtherm
    • Hunter Panels LLC (Carlisle)

      • H-SHIELD Polyisocyanurate added June 2015
      • Carlisle Polyisocyanurate added March 2013
    • Sika Sarnafil Canada Inc.

      • Sarnatherm
      Added

      2014-11

    • Soprema Inc.

      • Sopra-ISO (e) added January 2016
      • Sopra-ISO (s) added January 2016
      • Sopra-ISO (r) added January 2016
      • Sopra-ISO added October 2016
      • Sopra-ISO Plus added October 2016
  2. Expanded Polystyrene Roof Insulation

    • Beaver Plastics Ltd.

      • Terrafoam Type 1
      • Terrafoam Type 2
    • Plasti-Fab Ltd.

      • Plasti-Span Type 1
      • Plasti-Span Type 2
      • Plasti-Span Type 3
    • EPS Molders

      • Type 1
      • Type 2
      Added

      2015-04

  3. Extruded Polystyrene Insulation

    • Owens Corning Canada

      • Foamular C-300 & 350
      Revised

      2010-12

    • Dow Canada

      • DeckMate Type 2
      • DeckMate 200 Type 3
      • RoofMate Type 4
      • Deckmate PLUS FA (added 2016-01)
  4. Mineral Fiber Roof Insulation

    • Soprema Inc.

      • Soprarock DD (Plus)
      Added

      2014-11

  5. Fiberboard Roof Insulation

    • MSL Louiseville Fibreboard Inc.

      • Wood Fibreboard Insulation
      Added

      2011-01

    • International Bildrite Inc.

      • RoofRite Coated Fiberboard
      Added

      2011-04

MB-5.8.2 Secondary Insulation

.1

Acceptance of secondary insulation and cover board products by the ARCA Warranty Ltd. are on an individual product basis. The acceptance criteria provide for specific manufacturing or application parameters pertaining to each listed product.
  • MSL Louiseville Fibreboard Inc.

    • Wood Fibreboard Insulation
    Revised

    2015-07

  • International Bildrite Inc.

    • RoofRite Coated Fiberboard
    Added

    2011-04

  • Soprema Inc.

    • Soprarock DD (Plus) or 25mm (1”) thick Soprarock MD (Plus)

MB-5.8.3 Asphalt Core Boards

  • IKO Industries Ltd.

    • Min. 3.2mm (1/8”) thick Protectoboard
  • Soprema Inc.

    • Min. 3.2mm (1/8”) thick Sopraboard
  • Hal Industries Inc.

    • Min. 4.8mm (3/16”) thick Perma-board

MB-5.8.4 Gypsum Fiber Roof Boards

  • CGC Inc.

    • 9.5mm (3/8"), 12.7mm (1/2") or 15.9mm (5/8") thick Securock Gypsum Fiber Roof Board when accepted by membrane manufacturer.
Revised

2016-10

MB-5.8.5 Fibreglass Faced Gypsum Roof Boards

  • Georgia-Pacific Gypsum

    • Minimum 6.4mm (1/4”) thick Dens-Deck, Dens-Deck Prime and Duraguard

MB-5.8.6 High Density (HD) Polyisocyanurate Cover Boards (Mechanically Fastened Systems Only)

  • Atlas

    • Minimum 12.7mm (1/2") ACFoam HS Coverboard
    Revised

    2016-04

  • Firestone

    • Minimum 12.7mm (1/2") Isogard HD
    Revised

    2016-04

  • Hunter Panels / Carlisle

    • Minimum 12.7mm (1/2") SecurShield HD
    Revised

    2016-04

  • IKO

    • Minimum 12.7mm (1/2") IKOTherm Covershield
    Revised

    2016-04

MB-5.9 Polyurethane Foam Adhesive for Insulation and Cover Board

MB-5.9.1 General

.1

A primary membrane manufacturers’ accepted low-rise two component, chemical cure, polyurethane foam adhesive, when used in compliance with the manufacturer’s written application instructions, may be used to uniformly adhere accepted primary and secondary insulation, asphalt core boards, gypsum roof boards, high density polyisocyanurate cover boards and factory laminated base sheets to one another, to accepted vapour retarders, insulation and substrates.

.2

The primary membrane manufacturers’ insulation adhesive(s) have been evaluated by ARCA Warranty Ltd. for specific applications and are not accepted as general purpose roofing adhesives and are not to be substituted for other accepted primary membrane manufacturers insulation adhesives.

.3

Prior to dispensing, store adhesive at recommended application temperature and ensure adhesive shelf life date has not been exceeded.

.4

Insulation adhesives may be dispensed to clean moisture free substrate surfaces, by wand or spray equipment, applied in accordance with adhesive manufacturer’s application rates. For wand applications, maintain proper adhesive ribbon size and spacing for roof field, perimeter and corners. When spraying, maintain minimum coverage rates.

.5

Protect newly applied insulation adhesive from contamination prior to bonding roofing components. Follow manufacturer’s post application requirements for weighting, rolling or walk-in insulation boards into the uncured adhesive to prevent air gaps from forming between insulation boards and their supporting substrate.

.6

When polyisocyranurate roof insulation forms the primary insulation layer, insulation boards shall not exceed 1200mm x 1200mm (4' x 4') in size.
Added

2015-01

MB-5.9.2 Accepted Roof Insulation Adhesives

.1

The adhesives listed below by membrane manufacturer have been evaluated and accepted for specific applications. Accepted adhesives are not general purpose roofing adhesives and are not interchangeable amongst membrane manufacturers.
  1. Polyurethane Foam Insulation Adhesive

    Two component low-rise, chemically cured urethane foam adhesive for the attachment of selected rigid roof insulation and cover boards to one another and to fully adhered vapour barriers.

    • Soprema Inc. (Accepted Soprema Systems Only)

      • Duotack Roof Insulation and Coverboard Adhesive
      • DUOTACK 365 Roof Insulation and Coverboard Adhesive added October 2016
      Revised

      2012-09

    • IKO Industries Ltd. (Accdepted IKO Systems Only)

      • Roofcraft Roofmix Two Part Insulation Adhesive
      • IKO Millennium Adhesive
  2. Other Insulation Adhesives

    When approved for application by the membrane manufacturer and accepted by ARCA Warranty Ltd. on a project by project basis.

    • Dow Canada (As approved by Dow Technical Services)

      • Insta-Stik Professional Roofing Adhesive (one component polyurethane foam)
      Revised

      2012-12

    • Siplast Canada Inc.

      • Siplast Parastik Adhesive (one component polyurethane foam)
      Added

      2011-12