Granosil plus STF (Silicone Primer)

Overview

Granosil’plus STF is a primer coat formulated for use with silicone resin bonded renders in external applications. It is based on a silicone resin binder and contains quartz with additional adherence additives. The primer is described as water vapour permeant, non-swelling, low stress and non-film forming, supporting its function as an intermediate layer beneath compatible render finishes.

Field of Application

The product is intended for use as a primer for all silicone resin bonded renders applied externally. It is used to prepare suitable substrates prior to the application of the final render coat.

Composition and Appearance

Granosil’plus STF is a quartz-containing silicone resin bonded primer incorporating special adherence additives.

The primer is supplied in colours matched to the colour of the top coat render. A wide range of colour tones is available, based on original colour samples. Colour tones with brightness references below 20 are not available. Due to weather-influenced drying processes, colour tone differences between sample areas and the finished surface may occur. For subsequent deliveries, any remaining material should be mixed with newly supplied material to maintain colour continuity.

Substrate Preparation

Substrates must be flat, load bearing, clean and dry before application. Any loose material must be removed, and uneven areas levelled where required.

The product must not be applied to substrates coated with plastic or shiny dispersion materials.

Relevant requirements of DIN18363, VOB Part C, and the applicable BFS instruction sheets must be observed in their latest editions.

Where substrate suitability is uncertain, further technical consultation is required before application.

Application Method

Granosil’plus STF is applied using a paint brush, brush or lambskin roller, depending on the nature of the substrate.

The product may be diluted with up to 10% water, depending on substrate conditions. The material must be stirred thoroughly before use.

Freshly applied primer must be protected from torrential rain and excessively rapid drying. In conditions of direct sunlight or wind exposure, protective measures such as covering the façade or scaffold are required.

Application must not be carried out when substrate or ambient temperatures are below 5°C.

Adjacent building elements such as windows and window sills must be adequately protected during application.

All tools and equipment must be cleaned with water immediately after use.

Coverage

Typical coverage is 0.2–0.3kg/m² per coat on even substrates. Actual coverage is dependent on substrate condition and should be confirmed by applying a test coat on site.

Storage and Handling

The product is supplied ready for processing in 25kg containers.

Containers must be stored in a cool, frost-free environment and protected from direct sunlight. When stored in unopened containers, the product can be stored for at least 1 year. Once containers are opened, the contents must be used within a short period of time.

Health, Safety and Disposal

Application must be carried out in accordance with the relevant safety guidance. Safety-related information is provided in the applicable safety data sheets.

Only empty containers may be returned for recycling. Waste material must be allowed to dry before disposal in accordance with key number 91206 for building waste.

Classification

The EU VOC limit value for this product (category A/c WB) is 30g/L. The product contains a maximum of 30g/L VOC.

Technical Data