Guide to Renovating External Wall Cracks - Baumit UK

How To Restore Facades With Small Surface Cracks 

Small cracks in a façade allow water to penetrate, which can then freeze in the winter, resulting in far greater damage.  Baumit has as simple solution for cracks smaller than 0.5mm.  All you need is Baumit FillPrimer and one of Baumit’s high-quality façade paints.

2 steps to a new facade

Cracks with a width of less than 0.5 mm are covered with the crack-filling, fibre-reinforced Baumit FIllPrimer to bridge the cracks ready to be finished in a paint topcoat.

Step 1

Oprava fasády s trhlinkami

Apply Baumit FillPrimer reinforcing primer to the old render to cover the hairline cracks and minor damage.

Step 2

Nová fasádna farba

Follow with a new coat of façade paint. Choose from Baumit StarColor, NanoporColor or PuraColor.

Step by step working instructions

1. Assess the existing walls

Fasáda s mikrotrhlinkami

Assess the size of cracks in the facade. The surface of the facade must be firm and free of dust and algae. Brush or pressure wash the dusty and dirty facade and remove any other deficiencies.

2. What do you need?

Fasáda s mikrotrhlinkami

You will need Baumit FilPrimer bonding primer, a new façade paint, a façade roller or equipment for machine application of the façade paint.

3. Bonding primer

Penetračný náter na mikrotrhlinky

Sufficiently stir the Baumit FillPrimer in a bucket. If necessary (e.g. during very hot weather) it is possible to add max. 5% water (max. 1 L water/25 kg bucket).

4. Cracks coverage

Prekrytie trhlín na fasáde

Apply Baumit FillPrimer to the old render with a roller or brush, evenly without breaks. The coat will bond the cracks up to 0.5 mm in width. Curing time before application of the next layer is minimum 24 hrs.

5. New facade coat

Nová fasádna farba

Apply two layers of high quality façade paint to the clean façade. The first coat is applied diluted with 10 - 15% water. After a break of a minimum of 12 hours, apply 1 to 2 coats of the facade paint as required. Allow a minimum of 4 hours between each coat.

6. Facade paint spraying

Striekanie fasádnej farby

Baumit façade paint may also be applied using an airless spray machine. It allows fast and even application of the facade paint in a short time, perfect for large surfaces.

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