Bitumen-sam (membranes, primers)

CERESIT BT 21
Sealing membrane

Self-adhesive membrane for reliable waterproofing of buildings in the temperatures above 5 °C

Immediately water- and rain resistant
Cold-applied
Flexible and crack-bridging

TDS (1)

CERESIT BT 21

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Bitumen-sam (membranes, primers)

CERESIT BT 26

Bitumen-rubber emulsion used for priming self-adhesive membranes, sealing strips and fixing tapes.

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Cement slurries rigid

CERESIT CR 90

For waterproofing buildings and structural components forms a waterproofing layer on the substrate of the substrates and additionally, during the structure exploitation, it builds crystals in the substrate pores.

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Description
How to Use
FAQ

Product Description

CERESIT® BT 21 is used for sealing vertical and horizontal surfaces of buildings, structural components and below the ground structures, such as underground car parks and subways. It is suitable for waterproofing basement walls, garage roofs, balconies, terraces, wet rooms and patios. Also used as a sealant against capillary rise of moisture and as a water vapour barrier in floor areas under screeds.

Immediately water- and rain resistant
Cold-applied
Flexible and crack-bridging
In combination with BT 26 applicable also on moist surfaces
Amount required: 1.08 m2/m2

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How to Use

SUBSTRATE PREPARATION FOR APPLICATION OF CERESIT BT 21

Before installing the BT 21 waterproofing membrane, all mineral substrates must be pretreated with a BT primer. At temperatures above +5 °C, use BT 26 "AllWeather" Primer, at lower temperatures use BT 28 Special Primer (solvent-based).

APPLICATION OF CERESIT BT 21

Slowly and uniformly peel approx. 1 m backing paper off the strip's top edge. Align the strip and fix it to the substrate with the adhesive side down. Continue to peel off the paper and to bond the remaining part of the strip. After that, press the entire strip firmly down, e.g. with a rubber roller.

IMPORTANT TO NOTE WHEN USING CERESIT BT 21

Use the BT 21 »All-Weather« Waterproofing Membrane only in dry conditions at temperatures from –5 °C to +30 °C (but not in blazing sunshine) and below 80 % relative air humidity.

Frequently asked questions

CERESIT BT 21 is suitable for waterproofing basement walls, garage roofs, balconies, terraces, wet rooms and patios. Also used as a sealant against capillary rise of moisture and as a water vapour barrier in floor areas under screeds.

Looking to Upgrade?

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Cement slurries rigid

CERESIT CR 90

For waterproofing buildings and structural components forms a waterproofing layer on the substrate of the substrates and additionally, during the structure exploitation, it builds crystals in the substrate pores.

...

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