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EPDM Section 5: Insulation

EPDM-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, such as the Underwriters’ Laboratories of Canada (ULC) or a Canadian Construction Materials Centre (CCMC) evaluation listing to verify compliance to an existing 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.
Revised

2012-03

.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 sleepers.

.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.

.6

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

2017-11

EPDM-5.2 Primary Insulation

.1

The primary insulation may be loose-laid, mechanically fastened or uniformly adhered to the vapour retarder depending on the system type chosen.

.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. Primary insulation 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.
Revised

2010-06

.4

When insulation is adhered with adhesive or hot bitumen, restrict board size to maximum 1200mmx1200 mm (4 x 4 ft.) dimensions for proper adhesion.

.5

For loose-laid ballasted E.P.D.M. designs, the primary insulation layer shall be minimum 38mm (1.5”) thick for all insulation types except fiberboard or perlite insulation where the minimum thickness may be 25mm (1”) thick.

.6

For dark colored E.P.D.M. loose-laid ballasted membrane designs, incorporating Type 4 extruded polystyrene insulation, a polyethylene film shall temporarily cover the exposed membrane to prevent insulation deformation and shall be removed just prior to ballast placement.

.7

For mechanically fastened E.P.D.M. membranes applied over accepted polyisocyanurate primary insulation without a cover board, the insulation board, or top layer in a multi-layered application, 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.
Added

2010-12

.8

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

.9

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

EPDM-5.3 Insulation Cover Board

EPDM-5.3.1 Fiberglass Faced Gypsum Roof Board

.1

Minimum 6.4mm (1/4”) thick fiberglass faced gypsum roof board may be used for the attachment of primary membranes when approved as a horizontal substrate by the membrane manufacturer. Paper-faced gypsum board is not permitted for W.C. issuance.
Added

2010-06

.2

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 approved adhesive, hot bitumen, or mechanically attached to the roof decking following the membrane manufacturer’s written securement requirements.

.4

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

.5

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

EPDM-5.3.2 High Density Polyisocyanurate Cover Boards

.1

High-density (HD) polyisocyanurate cover board with a thickness of 12.7mm (1/2”) is an accepted insulation cover board for the application of mechanically fastened primary membranes only. Do not use high-density polyisocyanurate under loose-laid ballasted membranes
Added

2013-04

.2

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

EPDM-5.4 Accepted Roofing Insulation

EPDM-5.4.1 Primary Insulation

.1

Each listed insulation manufacturer has confirmed third party product certification by an accredited independent testing agency, in accordance with 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 2015-08)
      • Carlisle Polyiso
      Revised

      2015-06

    • 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)
    • Soprema

      • Sopra XPS 35
      • Sopra XPS 40
      • Sopra XPS 60
      Added

      2018-10

  4. Mineral Fiber Roof Insulation

    • Soprema Inc.

      • Soprarock DD (Plus)

EPDM-5.4.2 Insulation Cover Boards

.1

Acceptances of secondary insulation and cover board products by the ARCA Warranty Ltd. is on an individual product basis. The acceptance criteria provide for specific manufacturing or application parameters pertaining to each listed product. (Refer to EPDM 3.1.1.5.)
Revised

2016-04

  • Soprema Inc.

    • Soprarock DD (Plus)
    Added

    2014-11

  • MSL Louiseville Fibreboard Inc.

    • Wood Fibreboard Insulation
  • International Bildrite Inc.

    • RoofRite Coated Fiberboard
    Added

    2011-04

EPDM-5.4.3 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

EPDM-5.4.4 Fibreglass Faced Gypsum Roof Boards

  • Georgia-Pacific Gypsum

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

EPDM-5.4.5 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

  • IKO

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

    2016-04

  • Hunter Panels/Carlisle

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

    2016-04

EPDM-5.5 Polyurethane Foam Insulation and Cover Board Adhesive

EPDM-5.5.1 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 polyisocyanurate roof insulation forms the primary insulation layer, insulation boards shall not exceed 1200mm x 1200mm (4' x 4') in size.
Added

2015-01

EPDM-5.5.2 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.

    • Firestone Building Products Canada

      • ISO Twin Pack Roof Insulation Adhesive
      Revised

      2010-06

    • Carlisle SynTec Canada

      • FAST Adhesive Dual Cartridge
  2. Other Insulation Adhesives

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