Salt-retardant and Waterproofer for use in Re-plastering Applications.
Renderguard Gold is a high specification plaster additive that forms an integral part of the Safeguard Damp-proofing System (British Agrément Certificate No. 97/3363). Renderguard Gold has the following features:
Reduces water demand
Instils Salt-Retardant and Waterproofing properties
Remains vapour permeable
Economical – 25litres concentrate makes 625 litres ready-for-use.
Following DPC injection, correct re-plastering is of the utmost importance. Even though the damp-proof course is effective, hygroscopic salts introduced by rising damp may cause moisture to be attracted to the wall. This causes further dampness and decorative spoiling, giving the impression that the damp-proof course has not been successful.It is for this reason that the re-plastering following DPC injection must perform two functions:
It must prevent the passage of residual moisture reaching the decorative surface during the drying process, as well as control the limitations of the injection system itself.
It must prevent the passage of hygroscopic salts from the underlying masonry to the new decorative surface in order to prevent further spoiling.
Renderguard Gold will fulfil these requirements provided that the specification is strictly adhered to.
Timber skirtings, architraves etc should be removed as outlined in the survey report/specification.
Remove plaster back to the masonry to the height specified in the survey report/specification. This height should be no less than 1 metre or 300mm above the maximum level of visual rising dampness and/or salt contaminated plaster.
Rake out all mortar joints to a depth of 15mm. This is important in order to help resist the natural shrinkage of new cement renders.
Remove any timber fixing grounds that are present in the masonry.
Mix 1 part Renderguard Gold with 24 parts water. All water should be fresh, clean and free
from oil or other organic contaminants.
Prepare 3 parts sand and 1 part cement using the dilute Renderguard Gold solution prepared above in lieu of water. The sand should be specified as washed, sharp sand, loam-free which satisfies British Standard BS 882:1992 “M” Grading.
Use the minimum Renderguard Gold gauging solution to ensure a dense coat. As a guide, no more than 8 litres should be used for every 50kg of dry mix. Compact resulting mix well into raked out joints and render to give an overall thickness of
12mm. Do not over-trowel. When cement achieves first set, scratch to form a key.
The mix is as for the first coat except that water is used instead of Renderguard Gold solution. This is applied as a further 12mm coat giving a total thickness of 24mm for both coats. This
coat should be applied before the first coat has finally set in order to obtain a satisfactory
adhesion between the two coats. Flout to a smooth finish.
No decoration should take place for at least 6 weeks after treatment (or until the wall has dried out). After this time we recommend that only low solids emulsion paints are used (PVA). We
do not recommend the use of wallpaper or high build paints such as enamels.
1 litre of concentrate is sufficient for 7m² of render at 12mm thickness.