[CCMC 12416-R] CCMC Canadian code compliance evaluation

It is the opinion of the Canadian Construction Materials Centre that the evaluated products, when used as exterior wall cladding designed to be a weather barrier and to provide thermal insulation in accordance with the conditions and limitations stated in this evaluation, comply with the following codes:

National Building Code of Canada 2015

National Building Code of Canada 2020

Ontario Building Code

Ruling No. 95-03-022 (12416-R) authorizing the use of this product in Ontario, subject to the terms and conditions contained in the Ruling, was made by the Minister of Municipal Affairs and Housing on 1995-03-02 (revised 1998-05-15) pursuant to s.29 of the Building Code Act, 1992 (see Ruling for terms and conditions). This Ruling is subject to periodic revisions and updates.

The above opinion(s) is/are based on the evaluation by the CCMC of technical evidence provided by the evaluation holder, and is bound by the stated conditions and limitations. For the benefit of the user, a summary of the technical information that forms the basis of this evaluation has been included.

Product names

• StoTherm®ci Classic
• StoTherm®ci Essence
• StoTherm®ci Lotusan

Product description

The products are non-loadbearing exterior insulation and finish systems (EIFS) that can be assembled in panels under factory-controlled conditions, or field-applied. The systems are composed of the following key components:

• A water-resistive barrier (WRB);
• An adhesive;
• An insulation board; and
• A coating system (lamina).

Note: The lamina refers to all coats (base and finish) applied to the outer face of the insulation board with the glass-fibre mesh reinforcement.

The components of the systems are listed below.

Substrate

For applications falling under the scope of this Report, the substrate can be brick, masonry, monolithic concrete walls, and/or cementitious panels, glass mat surfaced gypsum boards, plywood or oriented strandboard (OSB) over wood or steel framing. Gaps between the sheathing boards of framed walls must not exceed 3.0 mm.

Water-resistive barrier (WRB)

The water resistive barrier (WRB) is a coating that is installed to provide, along with other built-in features, the second line of defence against water infiltration reaching the structure. The WRB must be applied in accordance with the product’s installation manuals.

In systems with a WRB, the continuity of the second plane of protection across joints and junctions at openings, penetrations and expansion joints must be maintained through the use of accessories such as self-adhering membranes, tapes, etc., as specified by the manufacturer, prior to the installation of these systems. Furthermore, in order to provide the intended level of protection against water infiltration, the WRB must be applied in two coats with sufficient time between applications to allow the first coat to cure before the second coat is applied.

The StoGuard^® coating system consists of two components: Sto Gold Fill^® with StoGuard^® Mesh or Sto Detail Mesh and Sto Gold Coat^®, which are fluid-applied over approved substrates to provide a monolithic air and moisture barrier:

• Sto Gold Fill^® is a water-based, flexible, trowel-applied joint compound that bridges sheathing joints and protects rough openings.
• Sto Gold Coat^® (81636) is a ready-mixed, water-based, flexible coating for direct application to vertical above-grade wall sheathing, concrete, and concrete masonry. Sto Gold Coat^® (81636) is applied in a continuous layer over the substrate and wrapped around the framing and penetration to achieve a minimum wet thickness of 0.41 mm (16 mils).

Sto Flexyl is a grey polymer-modified coating that is supplied in 19-L pails and mixed on site with 50% by weight Type GU Portland cement. Sto Flexyl is applied in a continuous layer over the substrate and wrapped around the framing and penetration to achieve a minimum wet thickness of 1.5 mm.

Sto Watertight Coat is a two-component, polymer-modified coating that is supplied in 19-L pails. The wet component and grey or white powder component are mixed on-site. Sto Watertight Coat is applied in a continuous layer over the substrate and wrapped around the framing and penetration to achieve a minimum wet thickness of 1.5 mm.

Adhesive

Sto BTS^® Plus is a one-component, polymer-modified, cement-based dry powder material used as an adhesive and supplied in 21.3-kg bags. Each bag is mixed with 4.7 L to 6.2 L of clean water. Sto BTS^® Plus is applied as an adhesive to the inward surface of the Sto insulation board using the appropriate notched trowel. For smooth substrates such as sheathing, use a stainless steel trowel with U-shaped notches measuring 13 mm × 13 mm at 64 mm on centre (o.c.). For uneven substrates such as some types of concrete masonry, use a trowel with square notches measuring 16 mm × 16 mm at 32 mm o.c. As a base coat, the product is applied in a single continuous layer over the insulation board to achieve a minimum thickness of 1.6 mm.

Sto Primer/Adhesive-B is a one-component, polymer-modified, cement-based, dry powder material supplied in 23-kg bags. Each bag is mixed with 4.7 L to 6.2 L of clean water. Sto Primer/Adhesive-B is applied as an adhesive to the surface of the Sto Corp. insulation board using the appropriate notched trowel. For smooth substrates such as sheathing, use a trowel with U-shaped notches measuring 13 mm × 13 mm at 64 mm o.c. For uneven substrates such as some types of concrete masonry, use a trowel with square notches measuring 16 mm × 16 mm at 32 mm o.c., or apply the product directly to the substrate using Sto Corp.’s M-8 spray pump and trowel with the appropriate notched trowel. As a base coat, the product is applied in a single continuous layer over the insulation board to achieve a minimum thickness of 1.6 mm.

Note: Adhesives are used for bonding the insulation to the substrate coated with the WRB. They are, in general, available in the following forms: a dry powder mix that requires the addition of water on-site, a wet paste that requires the addition of cement on-site, and a form that does not require any additives. Certain adhesives are also used as base coats.

Insulation

Sto EPS Insulation Board and Sto ProD EPS Insulation Board are manufactured and packaged by Sto Corp., qualified and licensed manufacturers/molders. The expanded polystyrene foam insulation boards are aged by air for a minimum of five weeks or kiln-dried.

Sto EPS Insulation Board is a typical flat EPS board.

Sto ProD EPS Insulation Board has drainage pathways cut into the insulation that conform with Clause 9.27.13.1.(1)(b) of Division B of the NBC 2015.

The two insulation boards must conform to the following:

• CAN/ULC-S701-11, “Standard for Thermal Insulation, Polystyrene, Boards and Pipe Covering,” Type 1 or Type 2;
• Minimum board thickness: 25 mm;
• Maximum board thickness:
  • as designed, when used in combustible construction;
  • 165 mm, when used in noncombustible construction meeting Article 3.1.5.5 of Division B of the NBC 2015 for StoTherm Systems and when applied over minimum 2 × 6 wood framing covered with a minimum 12.7-mm gypsum sheathing; and
  • 165 mm, when used in noncombustible construction meeting Clause 3.2.3.8.(1)(b) of Division B of the NBC 2015 for StoTherm Systems;
• Maximum board size: 600 mm × 1 200 mm;
• Nominal density: 16 kg/m³; and
• Flame-spread rating: 25–500, per CAN/ULC-S102.2-11, “Standard Method of Test for Surface Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies.”

Synthetic coating system (lamina)

The synthetic coating system (lamina) consists of the reinforcing mesh, which is embedded with the base coat, a primer and a finish coat.

Base coats

When Sto BTS^® Plus Sto Primer/Adhesive-B (see Adhesive) is used as a base coat, it is applied with a stainless-steel trowel to the entire surface of the insulation to a uniform nominal dry-rendered thickness of 1.6 mm.

Note: The required thickness of the base coat depends on the number of layers and the type of reinforcing mesh used. The base coat is thicker when more than one layer of reinforcing mesh is incorporated into the lamina. Ultimately, it must be thick enough to fully embed the reinforcing mesh into the base coat with no mesh colour visible.

Reinforcing mesh

The reinforcing mesh is an alkali-resistant, interwoven glass-fibre reinforcing fabric having a minimum 142 g/m² nominal weight that is used with the Sto Corp. base coats and the Sto Flexyl coating. The mesh is yellow or white (where noted) and available in 107-mm, 240-mm or 970-mm wide rolls. It is available in six grades of strength:

• Sto Detail Mesh:                         142 g/m², 240 mm wide
• Sto Mesh:                                    153 g/m², 970 mm wide
• Sto 6oz Mesh:                             203 g/m², 970 mm wide
• Sto Intermediate:                      373 g/m², 970 mm wide
• Sto Armor Mat:                          508 g/m², 970 mm wide
• Sto Armor Mat XX:                     678 g/m², 970 mm wide
• StoGuard^® Mesh:                     142 g/m², 107 mm and 240 mm wide

Primers

Sto Primer Smooth is a water-based acrylic smooth primer that provides uniform substrate absorption and finish colour and is supplied in 19-L pails. Sto Primer Smooth is applied by brush, roller or spray to the dry base coat and provides an approximately 0.1–0.15 mm wet thickness.

Sto Primer Creativ is a water-based acrylic primer supplied in 19-L pails. Sto Primer Creativ is applied by brush, roller or spray to the dry base coat and provides an approximately 0.1–0.15 mm wet thickness.

Sto Primer Sanded is a water-based acrylic sanded primer that provides uniform substrate absorption and finish colour and is supplied in 19-L pails. Sto Primer Sanded is applied by brush, roller or spray to the dry base coat and provides an approximately 0.1–0.15 mm wet thickness.

Note: Primer is typically required for spray- or roller-applied finishes.

Finish coats

Stolit^® Lotusan is an acrylic-based textured finish coat with graded marble aggregate supplied in 19-L pails. It is factory- or store-tinted to the desired colour. Finished thickness is 1.0–1.5 mm, depending on the texture selected.

Stolit^® is a ready-mix, acrylic-based, textured emulsion finish coat supplied in 19-L pails. It is factory- or store-tinted to the desired colour. Stolit^® is applied with a stainless-steel trowel or spray-applied to a 1.0–3.0 mm thickness, depending on the texture selected.

StoSilco^® Lit is a ready-mix, acrylic-based, silicone-enhanced, textured emulsion finish coat supplied in 19-L pails. It is factory- or store-tinted to the desired colour. StoSilco^® Lit is applied with a stainless-steel trowel or spray-applied to a 1.0–1.5 mm thickness, depending on the texture selected.

Sto Essence and Sto Element Finish is an acrylic-based textured finish coat with graded marble aggregate and DPR technology supplied in 19-L pails. It is factory- or store-tinted to the desired colour. Finished thickness is 1.0–1.5 mm, depending on the texture selected.

Sto exterior insulation and finish system (EIFS) elements

Manufacturing plants

This evaluation is limited to products produced at the following plants:

Product evaluated by the CCMC Indicates that the product from this manufacturing facility has been evaluated by the CCMC

The CCMC’s compliance opinion is bound by this product being used in accordance with the conditions and limitations set out below.

• The product is intended for use as an exterior wall cladding on buildings falling under the scope of Parts 5 and 9 of the NBC 2015 and the NBC 2020.
• When used in existing buildings, the applicable or the relevant elements of the existing buildings must comply with the requirements of the NBC 2015 and the NBC 2020.
• The products are intended to be used as exterior insulation and finish wall systems (EIFS) applied directly to vertical brick, masonry or monolithic concrete walls, and/or cementitious, glass mat surfaced gypsum, plywood or OSB-sheathing boards installed over wood or steel framing.
• Gaps between the sheathing boards of framed walls must not exceed 3.0 mm.
• The products are acceptable for use on vertical walls. The systems are not acceptable for use on horizontal surfaces. (Note: The present limitation doesn’t include protected soffit applications.)
• When the products are part of a prefabricated panel system that incorporates structural components, the prefabricated panel system must be designed by a professional engineer or architect in accordance with the manufacturer’s criteria and the requirements of the NBC 2015 and the NBC 2020.
• The products are not suitable for use as a structural sheathing for bracing purposes.
• The products are not intended for use as a below-grade insulation and should terminate at least 200 mm above grade level.
• For buildings within the scope of Part 5 of Division B of the NBC 2015, the system shall be designed in accordance with the requirements of Article 5.9.4.1., Structural Loads, Heat Transfer, Air Leakage, Vapour Diffusion and Water Penetration, of the NBC 2015.
• For buildings within the scope of Part 5 of Division B of the NBC 2020, the system shall be designed in accordance with the requirements of Article 5.9.4.1., Structural Loads, Heat Transfer, Air Leakage, Vapour Diffusion and Water Penetration, of the NBC 2020.
• When used in coastal areas on residential occupancies that fall under the scope of Part 9 of Division B of the NBC 2015, the products must be installed in conjunction with a capillary break conforming to Sentence 9.27.2.2.(1)(e) of Division B of the NBC 2015. Coastal areas are defined in Sentence 9.27.2.2.(5) of Division B of the NBC 2015.
• When used in coastal areas on residential occupancies that fall under the scope of Part 9 of Division B of the NBC 2020, the products must be installed in conjunction with a capillary break conforming to Sentence 9.27.2.2.(1)(e) of Division B of the NBC 2020. Coastal areas are defined in Sentence 9.27.2.2.(5) of Division B of the NBC 2020.
• The WRB coating must be applied in two coats.
• The continuity of the second plane of protection across joints and junctions at openings, penetrations and expansion joints must be maintained through the use of accessories such as self-adhering membranes, tapes, etc., as specified by the manufacturer, prior to the installation of these systems.
• The use of the products with the adhesives indicated in the Sto Exterior Insulation and Finish System (EIFS) Elements table is limited to geographical areas where the wind-design value is Q₅₀ < 1.0.
• When used on existing walls of sprinklered buildings or existing walls of the buildings with not more than 3 storeys, the possibility of moisture accumulation within the wall construction is mainly a function of 1) the ability of the wall assembly to deflect bulk water entry, and 2) the physical properties of the cladding being installed and its impact on the thermal, air leakage and vapour diffusion characteristics of the existing wall. The potential for moisture accumulation as a result of the addition of materials is very specific to the existing wall construction. Therefore, the installation must be in accordance with Appendix Note A-5.1.2.1(1), Application (Environmental Separation), of Division B of the NBC 2015 and the NBC 2020.
• For buildings within the scope of Part 9, Housing and Small Buildings, of the NBC 2015 and the NBC 2020, the design of the inboard/outboard insulation of the systems must be in accordance with the requirements of Section 9.25., Heat Transfer, Air Leakage and Condensation Control, of Division B of the NBC 2015and the NBC 2020.
• When the systems are used on existing walls, the addition of thermal insulation to existing exterior walls will increase the thermal efficiency and airtightness of the wall. Deficiencies in flashing and other elements in the building assembly, including mechanical systems, may result in detrimental effects of moisture accumulation as highlighted in Note A-9.25.2.4.(3), Loose-Fill Insulation in Existing Wood-Frame Walls, of Division B of the NBC 2015 and the NBC 2020. As a result, once the EIFS is installed, the existing exterior walls must meet the requirements of the NBC 2015 and the NBC 2020 for heat transfer, air leakage and condensation control.
• The products can provide additional thermal insulation to the wall assembly with no detrimental effects if properly designed and installed with knowledge of the existing wall configuration and performance.
• The products alone may not provide the full amount of the required wall insulation. The thermal resistance of the wall system must conform to the energy requirements of the applicable building code. The wall system may have to conform to the National Energy Code of Canada for Buildings.
• Before cutting into insulation boards, the polystyrene thermal insulation blocks must be aged for a minimum of five weeks or kiln-dried in accordance with the requirements of Section B2.1, “Aging,” of Annex B of CAN/ULC-S701, “Thermal Insulation, Polystyrene, Boards and Pipe Covering.”
• The polystyrene thermal insulation must be in conformance with the requirements of CAN/ULC-S701.
• The polystyrene thermal insulation boards must be cut from moulded blocks manufactured using 100% virgin raw materials.
• When used in combustible construction, the polystyrene insulation must be protected from the inside of the building in accordance with Clauses 3.1.4.2.(1)(c) and 9.10.17.10.(1)(c), Protection of Foamed Plastics, of Division B of the NBC 2015 and the NBC 2020.
• When used in noncombustible constructions, the polystyrene insulation must be protected from the inside of the building in accordance with Sentences 3.1.5.15.(2) and (3), Foamed Plastic Insulation, of Division B of the NBC 2015 and the NBC 2020.
• Where allowed by the Code through conformance to Sentence 3.1.5.5.(1), Combustible Cladding on Exterior Walls, of Division B of the NBC 2015 and the NBC 2020, “StoTherm®ci Lotusan,” “StoThetm®ci Classic” and “StoTherm®ci Essence” are acceptable for use on buildings required to be of noncombustible construction, where not more than three storeys in height if unsprinklered, and to an unlimited number of storeys if sprinklered, provided the interior surfaces of the wall assembly are protected by a thermal barrier conforming to Article 3.1.5.15., Foamed Plastic Insulation, of Division B of the NBC 2015 and the NBC 2020. For a detailed description of the compliance of “StoTherm®ci Lotusan,” “StoThetm®ci Classic” and “StoTherm®ci Essence” to the requirements of Sentence 3.1.5.5.(1) of Division B of the NBC 2015 and the NBC 2020, please refer to Intertek SPEC ID: 18818, Design No. STO/WDEIFS 25-01 Sto Category 1 Design Listing (please note that the wall assembly may include the use of wood-framing under some certain conditions , please refer to the Intertek fire listing for those conditions).
• Where allowed by the Code through conformance to Clause 3.2.3.8.(1)(b) of Division B of the NBC 2015 and the NBC 2020, “StoTherm®ci Lotusan,” “StoThetm®ci Classic” and “StoTherm®ci Essence” are acceptable for use in the exposed face of buildings required to be of combustible or noncombustible construction, provided the interior surfaces of the wall assembly are protected by a thermal barrier conforming to Article 3.1.5.15. of Division B of the NBC 2015 and the NBC 2020. For a detailed description of the compliance of “StoTherm®ci Lotusan,” “StoThetm®ci Classic” and “StoTherm®ci Essence” to the requirements of Clause 3.2.3.8.(1)(b) of Division B of the NBC 2015 and the NBC 2020, please refer to Intertek SPEC ID:  18188 Design No. STO/WDEIFS 15-01 Category 2 Design Listing (Please note that back-up wall assemblies covered by design listing do not include wood framing and wood sheathings and extend to non-combustible substrates only (steel stud over sheathings such as gypsum board, concrete, masonry and ICF)).
• The systems should be kept at least 50 mm or the distance required in applicable building regulations and safety codes from heat-emitting devices such as recessed light fixtures and chimneys.
• NBC 2015 and NBC 2020 requirements regarding fire stops must be implemented.
• The polystyrene thermal insulation must have a flame-spread rating of not more than 500 when tested in accordance with the requirements of CAN/ULC-S102.2-11, “Test for Surface Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies.”
• Movement joints are required to accommodate expansion and contraction of building materials due to thermal changes, moisture, wind, gravity, vibration and seismic activity. Movement joints in the cladding must be used in the following situations:
  • at joints that occur in the substrate;
  • at any abutment of the system with other materials;
  • where changes in substrate might create deflection or movement;
  • where significant structural movement occurs;
  • where deflections in excess of L/240 are expected; and
  • at the floor line in wood-frame construction (this may not be required where fully-engineered framing and floor systems are used)
• Closed-cell backer rods should be used at expansion joints so that the low-modulus sealant can be installed as per the seal

This evaluation is based on demonstrated conformance with the following criteria:

The evaluation holder has submitted technical documentation for the CCMC’s evaluation. Testing was conducted at laboratories recognized by the CCMC. The corresponding technical evidence for this product is summarized below.