Sika Boom-558 Flex - Low Expansion Flexible PU Foam - Sika

Sika Boom-558 Flex - Low Expansion Flexible PU Foam - Sika

Sika Boom-558 Flex is a flexible polyurethane foam , mono-component, self-expanding, for spray application.

It is ideal for filling connection joints around window and door frames, as it has low subsequent expansion as well as low expansive pressure.
Thanks to its flexibility, it can withstand large movements in the joints.

Features

• Flexible.
• Low expansive pressure.
• Low subsequent expansion.
• Does not contain chlorinated paraffins.
• Mono-component, ready to use.
• Good dimensional stability after polymerization (no subsequent shrinkage or expansion).
• Good thermal insulation.
• Can be cut, sanded and painted.
• Professional application with gun.

Application areas

The product is designed for:

• Insulation and filling of cavities and voids.
• Filling joints around window and door frames.
• Insulation against cold and drafts.
• Filling around pipes/duct penetrations.

The product can be used for interior and exterior applications.

Application

1. Pre-wet the substrate with clean water.
   This helps ensure that the foam cures properly and prevents unwanted foam expansion.
   If the ambient and/or substrate temperature is 0°C or lower, then do not pre-wet the substrate.
2. Shake the aerosol well for at least 20 times before use.
   Repeat agitation after long breaks in use.
3. Remove the cap from the aerosol.
   Screw the aerosol onto the thread of the application gun.
4. Dispense the foam by pressing the trigger.
   To ensure proper flow, hold can upside down while dispensing.
   The amount of foam extruded can be adjusted by applying more or less pressure to the trigger or by using the flow adjustment screw on the applicator gun.
5. Fill deep seams in several layers.
   Allow each coat to expand and harden sufficiently before wetting it again with water for the application of the next coat.
   Only partially fill voids/cavities as the foam expands during curing.
   Small voids can be filled using an extension tube, however this will reduce foam flow.
   Before removing the aerosol, put anything left in the aerosol into a container for safe disposal.
6. Removing aerosol without emptying it first can cause foam to splatter.
   Clean the application gun with Sika Boom Cleaner directly after use.
   Removing the aerosol without thoroughly cleaning it with Sika Boom Cleaner may damage the application gun.

Consumption

Joint yield based on 20 mm × 50 mm joint

• Foam yield per aerosol: 44 litres.
• Yield in joint: 29 meters.

Conditioning

Aerosol of 750 ml in blue color.