Lime Green turns 21

Silic8 Silguard - Stabilising Water Repellent

Silguard is a powerful, highly breathable treatment designed for lime and other mineral backgrounds. Silguard reduces water penetration and surface dusting, making it the ideal alternative to acrylic sealers for a wide range of lime plasters, renders, floors and related materials. 

Silguard contains  waterglass and siloxane to harden slightly dusty surfaces and make them water repellent. This enables it to be used to protect unpainted mineral plasters, such as Lime Green Solo, to give enhanced water repellence to external renders or limewash and to protect breathable floors. Other porous mineral surfaces such as cement are also suitable, after trials to check compatibility. Silic8 Silguard is highly breathable and will not trap moisture vapour.  

Unsuitable backgrounds for Silguard water repellent treatment include dolomitic limestone, gypsum or related materials, walls or floors with salt contamination, retaining walls or walls with a hydrostatic head of water. 


Find Supplier

Data Sheet

View technical information about this product here. If you require any other information please contact us


Click on a button to download an associated document. The document will open in your web browser. To Download the document, 'right click and save to downloads.'


Colour Clear and matt; minimal change in appearance for most surfaces. Test before full application. 

Packaging  5 litre and 10 litre UN cans 

Storage  Store between 5°C and 25°C, protect from frost and direct sunlight. Silguard is naturally alkaline and biocide free. Shelf life is 12 months. 

Coverage From 0.25 to 0.75 litres per m2 on typical backgrounds. Coverage will vary with surface roughness and porosity.  

Performance  Sd Value    0.03 m  EN ISO 7783-2 

Preparation: Backgrounds should be sound and free from organic growth, dirt and oils. Lightly dust surfaces are acceptable, but for heavily dusting surfaces repairs should be made first. Do not apply to backgrounds with salt or detergent contamination. When used as an external water repellent any present building defects should be fixed first (e.g. defective pointing or gutters, leaks should be resolved). Do not use Silguard as an alternative to maintenance or good detailing. Backgrounds must be mineral, porous and dry. Wet or waterproofed backgrounds will lead to the Silguard running off before it can harden.  

New renders and plasters should be left to dry and carbonate before water repellent treatment. Time spans will depend on weather conditions, but generally an absolute minimum of 4 weeks.  Carefully mask off all glass, frames and other surfaces not to be treated. Silguard will etch and react with glass and may stain other materials.  Always test a small area first to check compatibility. Do not attempt to treat wet or damp masonry; if the solution turns a milky colour then the solution has not attached due to the damp background. 

 To find out more about any of our products or build systems, and how you can use them effectively, call Lime Green today on 01952 728611 or email us and we'll be happy to answer your questions.