Sikaflex®-740 Construction
Sikaflex®-740 Construction is a 1-component, moisture-curing, elastic joint sealant, designed for movement and connection joints and optimised for non-staining skim coat and over paint ability within few days of sealant application
- Non-staining on most skim coats and paints
- Very good resistance to weathering
- Movement capability of ± 35 (ASTM C 719)
- Very good adhesion to porous substrates
- Very good adhesion to most metals
- Bubble-free curing
- Good workability
- Very low emissions
Usage
Sealing joints for:- Joints requiring skim coat and paint application over sealant
- Movement and connection joints
- Interior and exterior use
- Low and highrise residential properties
- Facade, pre-cast and modular building elements
- Window and door frames
Advantages
- Non-staining on most skim coats and paints
- Very good resistance to weathering
- Movement capability of ± 35 (ASTM C 719)
- Very good adhesion to porous substrates
- Very good adhesion to most metals
- Bubble-free curing
- Good workability
- Very low emissions
Packaging
300 ml cartridges | 12 cartridges per box |
600 ml cylindrical foil pack | 20 foil packs per box |
Refer to the current price list for available packaging variations.
Colour
Colour range to be defined by local sales organisation.
Product Details
SUSTAINABILITY
Conforms with LEED v4 EQ credit: Low-emitting materials
VOC Test Report, SCAQMD Rule 1168, LEED v4.1, Sikaflex-740 Construction, Eurofins, Report No. 392-2021-00292706_XG_EN
VOC Emission Test CDPH, Sikaflex®-740 Construction, Eurofins, Report No.392-2021-00292703_H_EN
APPROVALS / CERTIFICATES
Joint Classification, ASTM C920 , Class 35, Sikaflex®-740 Construction
Product declaration
ASTM C920 - Type S, Grade NS, Movement Class 35, Use T1, NT, M
Composition
i-Cure® Technology polyurethane
Shelf life
12 months from date of production
Storage conditions
The product must be stored in original, unopened and undamaged packaging in dry conditions at temperatures between +5 °C and +25 °C. Always refer to packaging.
Density
1.45 kg/l | (ISO 1183-1) |
Shore A hardness
~30 (after 28 days) | (EN ISO 868) |
Tensile strength
~1 MPa | (ISO 37) |
Secant tensile modulus
0.6 N/mm² at 60 % elongation (23 °C) | (ISO 8339) |
Elongation at break
~800 % | (ISO 37) |
Movement capability
± 35 % | (ASTM C719) |
Elastic recovery
~80 % | (ISO 7389) |
Tear propagation resistance
~6.0 N/mm | (ISO 34-2) |
Service temperature
Maximum | +70 °C |
Minimum | −40 °C |
Joint design
The joint dimensions must be designed to suit the movement capability of the sealant. A width to depth ratio of 2:1 must be maintained. Joint widths less than 10 mm are generally for interior connection joints or crack control joints and therefore considered as non-movement joints.
All joints must be correctly designed and dimensioned in accordance with the relevant standards and codes of practice before their construction. The basis for calculation of the necessary joint widths are:
The type of structure
Dimensions
Technical values of adjacent building materials
Joint sealing material
The specific exposure of the building and the joints
CALCULATION GUIDELINE FOLLOWING ASTM C1472‐10 WITH A CLASS 35 SEALANT TO ASTM C920
Joint distance | Minimum joint width | Minimum joint depth |
2 m | 10 mm | 10 mm |
4 m | 15 mm | 10 mm |
6 m | 15 mm | 10 mm |
8 m | 25 mm | 12 mm |
10 m | 30 mm | 15 mm |
12 m | 35 mm | 17 mm |
14 m | 40 mm | 20 mm |
For joint design and calculations contact Sika Technical Services for additional information.
Application
Material temperature
Maximum | +40 °C |
Minimum | +5 °C |
Ambient air temperature
Maximum | +40 °C |
Minimum | +5 °C |
Substrate temperature
Maximum | +40 °C |
Minimum | +5 °C |
Temperature must be a minimum of +3 °C above dew point temperature
Backing material
Use closed cell, polyethylene foam backing rod or backing tape.
Curing rate
~3 mm/24 hours (23 °C / 50 % r.h.)
Skinning time
~60 minutes (23 °C / 50 % r.h.)
Tooling time
~30 minutes (23 °C / 50 % r.h.)
Consumption
| Joint width | Joint depth | Joint length per 600 ml foil pack |
| 10 mm | 10 mm | 6 m |
| 15 mm | 10 mm | 4 m |
| 20 mm | 10 mm | 3 m |
| 25 mm | 12 mm | 2 m |
| 30 mm | 15 mm | 1.3 m |
Note: Consumption data is theoretical and does not allow for any additional material due to surface porosity, surface profile, variations in level, wastage or any other variations. Apply product to a test area to calculate the exact consumption for the specific substrate conditions and proposed application equipment.
MIXING
1-part ready to use
APPLICATION
IMPORTANT
Strictly follow installation procedures
Strictly follow installation procedures as defined in Method Statements, application manuals and working instructions which must always be adjusted to the actual site conditions.
- Apply masking tape where neat or exact joint lines are required. Remove the tape within the skinning time of the Product after finishing.
- After the required substrate preparation, insert a backing rod to the required depth.
- Prime the joint surfaces as recommended in substrate preparation. Avoid excessive application of primer to avoid causing puddles at the base of the joint.
- The Product is supplied ready to use. Prepare the end of the foil pack or cartridge, insert into the sealant gun and fit the nozzle. Extrude the Product into the joint ensuring that it comes into full contact with the sides of the joint and avoiding any air entrapment.
- IMPORTANT Do not use tooling products containing solvents. As soon as possible after application, tool the sealant firmly against the joint sides to ensure adequate adhesion and a smooth finish. Use a compatible tooling agent such as Sika® Tooling Agent N to smooth the joint surface.
CLEANING OF EQUIPMENT
Clean all tools and application equipment immediately after use with Sika® Remover-208. Once cured, hardened material can only be removed mechanically. For cleaning skin use Sika® Cleaning Wipes-100.