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A waterproofing admixture that is diluted with water. Can be added as a gauging solution to sand:cement or sand:lime repointing mixtures.

Product appears as a white/ milky liquid. Should be applied to the raked-out joint using a suitable pointing iron or repointing gun.


  • Significantly reduces the liquid water absorption of masonry.
  • Easy to mix into the repointing mortar mixture.
  • Functions with both cement- and lime-based mortars.
  • The modified mortar is breathable.

General information
Specification data
Product Reference

Stormdry Repointing Additive No.1

Standard product features


One 500 ml bottle will provide sufficient mortar to repoint an area of approximately 5 m² of masonry.


  • Before repointing mortar is applied, raked-out mortar joints should be wetted, e.g. by flicking water using a wet brush.
  • To be diluted with clean tap water in the ratio of one part Stormdry Repointing Additive No.1 to nine parts water by volume.