BIOKIL. Rendermix Plastering Additive
BIOKIL. Rendermix Plastering Additive - 5 Litre is backordered and will ship as soon as it is back in stock.
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BIOKIL. Rendermix Plastering Additive
BIOKIL. Rendermix – waterproofer, plasticiser and salt inhibitor for renders
Rendermix is a concentrated liquid waterproofing and plasticising admixture for sand and cement renders. Walls affected by rising damp are often contaminated with hygroscopic salts, which can cause damp patches to reappear – Rendermix gives the render salt and water resistance, making it the standard choice for re-plastering after a chemical DPC.
Key benefits
- Waterproofs render and inhibits salts
- Plasticises – improves workability
- Economical: diluted 1 part to 40 parts water (0.6 litres of concentrate + 24.4 litres of water = 25 litres of gauging solution)
Typical applications
Renders over damp-affected and salt-contaminated walls, re-plastering after DPC installation, basements and below-ground walls, and general internal or external rendering for improved durability and water resistance.
Re-plastering specification in brief
- Dilute 1:40 with clean water as the gauging solution. Do not add other plasticisers, washing-up liquid or gypsum plaster.
- First coat: 3 parts washed sharp sand to 1 part cement (sulphate-resisting cement where soot or groundwater contamination is present), using no more than about 8 litres of gauging per 50kg of dry mix. Apply 12mm thick and scratch.
- Second coat: a further 12mm (total approx. 25mm), applied before the first has fully set, then scratched.
- Finish: a 3mm skim of Limelite High Impact Finishing Plaster – do not over-trowel or polish.
Repair unstable masonry first (use expanded metal lath where a good bond can't be achieved) and keep render clear of the finished floor to avoid bridging the DPC. Paint can be applied after 7 days (BIOKIL. Anti-Mould Emulsion); delay re-papering for at least 12 months. Provide background heating and ventilation while drying.
Usage: average 2.0 litres of gauging solution per 50kg cement. Available in 5L and 25L; indefinite shelf life when stored correctly. Avoid contact with eyes.
Frequently asked questions
How do I dilute BIOKIL. Rendermix?
1 part Rendermix to 40 parts clean water by volume: 0.6 litres of concentrate plus 24.4 litres of water makes 25 litres of gauging solution. Do not add other plasticisers, washing-up liquid or gypsum plaster.
What render mix should I use?
3 parts washed, sharp sand to 1 part cement. Use sulphate-resisting cement where soot or groundwater has contaminated the wall. Use no more than about 8 litres of gauging solution per 50kg of dry mix.
How thick should each coat be?
First coat 12mm, scratched for a key. Second coat a further 12mm, applied before the first has fully set (about 25mm in total). Finish with a 3mm skim of Limelite High Impact Finishing Plaster.
When can I decorate?
Paint after seven days using BIOKIL. Anti-Mould Emulsion. Wait at least 12 months before re-papering.
What sizes are available, and how long does it keep?
5L and 25L. It keeps indefinitely if stored as instructed, in a cool, dry place.
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