SikaHyflex®-250 Facade
SikaHyflex®-250 Facade is a 1-component, moisture-curing, low-modulus elastic joint sealant.
- Very good weathering resistance
- Movement capability of +100 / −50% (ASTM C 719)
- Bubble-free curing
- Low stress to the substrate
- Very good extrusion and workability
- Good adhesion to many different substrates
- Solvent-free
- Very low emissions
Usage
SikaHyflex®-250 Facade is designed for the elastic joint sealing and waterproofing of movement and connection joints in building envelopes. Due to its very low modulus, SikaHyflex®-250 Facade is also suitable for EIFS Facades.Advantages
- Very good weathering resistance
- Movement capability of +100 / −50% (ASTM C 719)
- Bubble-free curing
- Low stress to the substrate
- Very good extrusion and workability
- Good adhesion to many different substrates
- Solvent-free
- Very low emissions
Packaging
300 ml cartridge, 12 cartridges per box
600 ml foil pack, 20 foil packs per box
Colour
Colour range to be defined by local sales organization.
Product Details
ENVIRONMENTAL INFORMATION
- EMICODE EC1PLUS R
- LEED v4 EQc 2: Low-Emitting Materials
APPROVALS / STANDARDS
- EN 15651-1 F EXT-INT CC 25 LM
- ISO 11600 F 25 LM
- DIN 18540 F
- ASTM C 920, class 100/50
Chemical Base
i-Cure® Technology polyurethane
Shelf Life
SikaHyflex®-250 Facade has a shelf life of 15 months from the date of production, if it is stored in undamaged, original, sealed packaging, and if the storage conditions are met.
Storage Conditions
SikaHyflex®-250 Facade shall be stored in dry conditions, where it is protected from direct sunlight and at temperatures between +5 °C and +25 °C.
Density
| ~1.35 kg/l | (ISO 1183-1) |
Shore A Hardness
| ~20 (after 28 days) | (ISO 868) |
Secant Tensile Modulus
~0.30 N/mm2 at 100% elongation (23 °C) | (ISO 8339) |
| ~0.60 N/mm2 at 100% elongation (−20 °C) |
Movement Capability
± 25% | (ISO 9047) |
| +100 / −50% | (ASTM C 719) |
Elastic Recovery
~80% | (ISO 7389) |
Tear Propagation Resistance
~5.0 N/mm | (ISO 34) |
Service Temperature
−40 °C to +70 °C
Resistance to Weathering
10 | (ISO / DIS 19862) |
Joint Design
The joint width must be designed to suit the joint movement required and the movement capability of the sealant. The joint width shall be ≥ 10 mm and ≤ 50 mm. A width to depth ratio of 2:1 must be maintained (for exceptions, see table below).
Standard joint widths for joints between concrete elements:
| Joint distance [m] | Min. joint width [mm] | Min. joint depth [mm] |
| 2 | 10 | 10 |
| 4 | 15 | 10 |
| 6 | 20 | 10 |
| 8 | 30 | 15 |
| 10 | 35 | 17 |
All joints must be correctly designed and dimensioned in accordance with the relevant standards, before their construction. The basis for calculation of the necessary joint widths are the type of structure and its dimensions, the technical values of the adjacent building materials and the joint sealing material, as well as the specific exposure of the building and the joints.
For larger joints please contact Sika Technical Service.
Application
Sag Flow
| 0 mm (20 mm profile, 50 °C) | (ISO 7390) |
Ambient Air Temperature
+5 °C to +40 °C
Substrate Temperature
+5 °C to +40 °C, min. 3 °C above dew point temperature
Backing Material
Use closed cell, polyethylene foam backing rods.
Curing Rate
~3 mm/24 hours (23 °C / 50% r.h.) | (CQP 049-2) |
Skin Time
~70 minutes (23 °C / 50% r.h.) | (CQP 019-1) |
Tooling Time
~65 minutes (23 °C / 50% r.h.) | (CQP 019-2) |
Consumption
Joint length [m] per 600 ml foil pack | Joint width [mm] | Joint depth [mm] |
6 | 10 | 10 |
4 | 15 | 10 |
3 | 20 | 10 |
| 2 | 25 | 12 |
| 1.3 | 30 | 15 |
SUBSTRATE PREPARATION
The substrate must be clean, dry, sound and homogeneous, free from oils, grease, dust and loose or friable particles. SikaHyflex®-250 Facade adheres without primers and/or activators.
However, for optimum adhesion and critical, high performance applications, such as on multi-story buildings, highly stressed joints, extreme weather exposure or water immersion, the following priming and/or pre-treatment procedures shall be followed:
Non-porous substrates
Aluminium, anodised aluminium, stainless steel, galvanised steel, powder coated metals or glazed tiles have to be cleaned and pre-treated using Sika® Aktivator-205, wiped on with a clean towel. Before sealing, allow a flash-off time of > 15 minutes (< 6 hours).
Other metals, such as copper, brass and titanium-zinc, also have to be cleaned and pre-treated using Sika® Aktivator-205, wiped on with a clean towel. After the necessary flash-off time, use a brush to apply Sika® Primer-3 N and allow a further flash-off time of > 30 minutes (< 8 hours) before sealing the joints.
PVC has to be cleaned and pre-treated using Sika® Primer-215 applied with a brush. Before sealing, allow a flash-off time of > 30 minutes (< 8 hours).
Porous substrates
Concrete, aerated concrete and cement based renders, mortars and bricks shall be primed using Sika® Primer-3 N applied with a brush. Before sealing, allow a flash-off time of > 30 minutes (< 8 hours).
For more detailed advice and instructions please contact Sika Technical Services.
Note: Primers are adhesion promoters. They are neither a substitute for the correct cleaning of a surface, nor do they improve the strength of the surface significantly.
CLEANING OF TOOLS
Clean all tools and application equipment immediately after use with Sika® Remover-208 and/or Sika® Cleaning Wipes-100. Once cured, residual material can only be removed mechanically.