A Take On Render Failures:- WHAT CAUSES IT?

by Eva Spenser Innovation

Render failure can happen due to many reasons. So it is not right to isolate one specific cause for the overall damage.

In fact, Matt Denver- a rendering specialist serving Melbourne says clearly:-

“It is no big surprise to find more than one mode of failure, more so if you are dealing with more than one building elevation. And that is why before going ahead with render repair, it is important to figure out the root of the issue.”

A Take On Common Render Failure Causes:-

Signs Of Cracking:-

The first prime reason for the render failure is obviously the formation of cracks on the wall surface. These cracks permit the rainwater to seep into the walls and increase the risks of penetrating damp.

Reasons Why Cracks Form:-

Applying the render coat in poor or incongenial weather conditions, thus leading to shrinkage cracks.
Due to chloride, sulphate or other chemical attacks on the wall surface.
When the render characteristics do not support the underlying surface and substrate, thus causing it to expand and contract at vivid rates.

Debonding And Shelling:-

Shelling and debonding on buildings hampered with rainwater ingress because of a failure of the peripheral render system can make the structure unsound. It leads to inadequate bonding to the underlying substrate.

Reasons Why This Happens Are As Follows:-

Formation of ettringite between the render and the masonry that blows the render bond along with the wall.
Water getting behind the render coat and freezing which leads to a hydraulic action. This disrupts the bond between the substrate and the render coat.
Poor layering of the substrate with total reliance on an adhesive bond alone, rather than using a mechanical keyed bond with it.

Surface Erosion:-

Another common form of render failure is surface erosion. This is more prevalent in cementitious renders. Rainwater literally washes away the friable surface. And because such surfaces are saturated on the inside, it also leads to a secondary level of erosion resulting from a Thaw Action or hydraulic freeze.

This also causes internal penetrating damp issues and eventually will have to be removed or replaced with a fresh coat from render repair experts serving in and around Melbourne.

Substandard or Absence Of A Quality Sealant At Key Junctions:

Once the fresh coat of render is applied, it needs to be sealed with quality mastic at key junctions like door frames, boiler flues, windows, wall junctions, pipes, cable penetrations, etc. If not done, then the rendered treatment will take in rainwater, literally from day one and fail prematurely.

You can use low modulus silicone sealant as they are great for uPVC doors and windows. But then, there are other quality sealant products for a wide range of application needs.

To, avoid this, speak to the experts offering rendering services St Kilda about proper sealants.

Ending Statement:-

If your walls have similar render flaws, and are in need of immediate repair, then be sure to contact a notable rendering service provider in East Melbourne and get it repaired.

They are your best bet to fixing those render issues promptly and adequately.