Exterior Cladding Inspection

Per NBC Part 5 and Part 9, the building envelope must include a continuous weather resistive barrier (WRB) and air barrier system to control water penetration, air leakage, and vapour diffusion. The WRB must be lapped shingle-fashion with all joints sealed or taped. The air barrier must be continuous across the entire building envelope and sealed at all transitions, penetrations, and interfaces per NBC Section 5.4. All materials must be compatible and meet NBC durability requirements.

1. Verify the weather resistive barrier is installed shingle-fashion with minimum 150 mm horizontal laps and 100 mm vertical laps, sealed or taped per manufacturer's specifications

2. Confirm the air barrier system is continuous across the wall assembly with sealed connections at all transitions (wall-to-roof, wall-to-foundation, wall-to-window)

3. Check that all penetrations through the WRB and air barrier (services, fasteners, structural connections) are sealed with compatible materials

4. Verify the WRB is mechanically fastened and not relying solely on adhesive in high-wind zones per NBC

5. Confirm integration of the WRB with window and door flashings per CSA A440 installation requirements

- WRB laps reversed (installed counter to drainage direction) allowing water behind the barrier

- Air barrier discontinuities at structural connections and floor line transitions

- Penetrations through the WRB not sealed or sealed with incompatible sealant

- WRB damaged during construction and not repaired before cladding installation

Per NBC Part 5 and Part 9 (Section 9.27), cladding systems in locations receiving more than 1000 mm of annual precipitation must incorporate a rainscreen with a drained and ventilated air space behind the cladding. The drainage cavity must be a minimum of 10 mm clear for Part 9 buildings and designed per NBC Part 5 for larger buildings. The cavity must be open at the bottom for drainage and at the top for ventilation, with appropriate insect screening.

1. Verify the drainage cavity behind the cladding is a minimum 10 mm clear (19 mm preferred for wood frame per NBC Part 9)

2. Confirm drainage cavity is open at the base with flashing and weep openings to direct water outward

3. Check that ventilation openings are provided at the top and bottom of the cavity per NBC Part 5 requirements

4. Verify insect screening is installed at all drainage and ventilation openings (corrosion-resistant, minimum 3 mm mesh)

5. Confirm furring strips or clips maintain the required cavity width and do not compress insulation into the drainage space

- Drainage cavity blocked by mortar droppings, insulation, or debris preventing water drainage

- Weep openings omitted or sealed during finishing allowing water to accumulate behind cladding

- Ventilation openings insufficient for drying of the cavity moisture

- Insect screening missing allowing pest intrusion into the cavity

Per NBC Part 5 and Part 9, flashings must be installed at all transitions, intersections, and terminations of the cladding to direct water outward. This includes window and door head and sill flashings, floor line flashings, roof-to-wall flashings, and base-of-wall flashings. Flashings must be lapped and sealed to form a continuous water management system. Materials must be durable, corrosion-resistant, and compatible with adjacent materials.

1. Verify head flashings above all windows and doors extend beyond the jambs and are turned up behind the WRB per CSA A440

2. Confirm sill flashings are sloped to drain water outward with end dams to prevent lateral water movement

3. Check that base-of-wall flashings direct water from the drainage cavity to the exterior face of the cladding

4. Verify roof-to-wall flashings are step-flashed (not continuous) for sloped roofs and properly integrated with the WRB

5. Confirm all flashing laps are a minimum of 100 mm and sealed where required by the system design

- Head flashings not extending beyond window jambs allowing water entry at corners

- Sill flashings missing end dams permitting lateral water migration into the wall assembly

- Base-of-wall flashings terminated too high leaving the bottom of the drainage cavity unprotected

- Incompatible metals in flashing causing galvanic corrosion (e.g., aluminium against copper)

Per NBC Part 5 and Part 4 (structural), cladding must be securely attached to the building structure to resist gravity loads, wind loads (pressure and suction), and seismic forces per NBC. Fastener type, size, spacing, and penetration depth must comply with the cladding manufacturer's requirements and the structural engineer's design. For masonry veneer, brick ties must comply with CSA A370. For panel systems, clip and track systems must be designed for the specified loads.

1. Verify cladding fastener type, size, and spacing match the manufacturer's specifications and structural design for the wind zone

2. Confirm brick ties (for masonry veneer) are installed at maximum 800 mm horizontally and 600 mm vertically per CSA A370

3. Check that fastener penetration into structural members meets the minimum requirement (typically 32 mm into wood framing)

4. Verify panel cladding clips and tracks are level, plumb, and securely fastened to the structural backup

5. Confirm expansion and contraction joints are provided at intervals per the cladding manufacturer's requirements

- Fastener spacing exceeding the maximum for the wind zone causing cladding blow-off

- Brick ties corroded, missing, or not embedded properly in mortar joints

- Expansion joints omitted in long runs of cladding causing buckling or cracking

- Fasteners penetrating through the drainage cavity without sealant allowing water ingress

Per NBC Part 3 and CAN/ULC-S134, exterior wall assemblies on buildings requiring a fire resistance rating must limit vertical fire spread on the exterior face. Combustible cladding on buildings of non-combustible construction type must comply with NBC Article 3.1.5.5 and may require testing per CAN/ULC-S134. Fire stops must be provided in concealed spaces within the exterior wall assembly at each floor line and at fire separations per NBC.

1. Verify the exterior wall assembly complies with NBC Article 3.1.5.5 for combustible components on non-combustible construction types

2. Confirm fire stops are installed in the drainage cavity at each floor line to limit vertical fire spread per NBC Part 3

3. Check that combustible cladding materials have been tested per CAN/ULC-S134 where required by the building's construction type

4. Verify continuous insulation materials meet the required flame spread and smoke development ratings per CAN/ULC-S102

5. Confirm fire separations at property lines and between suites are maintained through the exterior wall assembly per NBC

- Combustible cladding installed on non-combustible construction types without CAN/ULC-S134 compliance

- Fire stops missing in the drainage cavity at floor lines allowing vertical fire spread

- Combustible insulation with inadequate flame spread rating installed without a thermal barrier

- Fire separation continuity broken at the exterior wall allowing fire passage between suites

Per NBC Part 5 and CAN/CGSB-19.13, sealant joints in exterior cladding must be designed to accommodate the expected movement of the cladding system. Joint geometry must provide proper width-to-depth ratio (typically 2:1) with a bond-breaker or backer rod to prevent three-sided adhesion. Sealant must be compatible with the substrate and applied within the manufacturer's temperature range. Joint design must account for thermal expansion, structural movement, and construction tolerances.

1. Verify joint widths are designed for the expected thermal movement of the cladding material per CAN/CGSB-19.13

2. Confirm backer rod or bond-breaker tape is installed to achieve proper joint geometry (width-to-depth ratio of 2:1)

3. Check that sealant type is compatible with both substrates and is rated for the expected movement (Class 25 or higher per ASTM C920)

4. Verify sealant is tooled to a concave profile with good adhesion to both sides of the joint

5. Confirm sealant was applied within the manufacturer's specified temperature and humidity range

- Three-sided adhesion due to missing backer rod causing premature sealant failure

- Joint width insufficient to accommodate thermal expansion resulting in sealant tearing

- Sealant applied to dirty or unprepared substrates with poor adhesion

- Sealant applied in temperatures below the manufacturer's minimum causing improper curing

Per NBC Part 9 (Section 9.20) and CSA A370, clay brick and stone veneer must be installed with proper ties, mortar joints, weep holes, and shelf angles. Mortar must comply with CSA A179 for the specified type. Weep holes must be provided at the base of the veneer, above all flashings, and above shelf angles at maximum 800 mm spacing. Shelf angles supporting masonry veneer must be designed per NBC Part 4 and installed with allowance for differential movement.

1. Verify mortar type matches the specification per CSA A179 (typically Type S for exterior above grade)

2. Confirm weep holes are installed at the base of walls, above all flashings, and above shelf angles at maximum 800 mm centres

3. Check that shelf angle joints include a minimum 15 mm soft joint below the masonry above to accommodate differential movement

4. Verify brick ties are properly embedded in mortar joints and spaced per CSA A370 requirements

5. Confirm control joints in the masonry are located per the design at maximum 6 m spacing and at changes in wall height or thickness

- Weep holes blocked by mortar droppings preventing drainage from behind the veneer

- Soft joints below shelf angles omitted or filled with mortar causing veneer cracking

- Mortar joints not tooled properly reducing weather resistance and durability

- Control joints missing or improperly located resulting in uncontrolled cracking