A seven year old green roof

Seven year old green roof

Green acrylic showing chalking after 7 years
Seven year old green roof showing chalking

Since the 1990s green acrylic (elastomeric) has tended to chalk before the reds, blacks and pastel tints.  The reason is that the liquid tint used for green interacts with the required zinc in acrylic formulas (Zinc prevents moss, mold, etc., from growing in the acrylic).  The powdered red and black tints resist chalking more effectively.

By year seven, a green acrylic roof may look like this photo taken on a rainy day at our 2004 customer’s home. 

Is the acrylic now “bad”?  Not at all.  The acrylic is still adhering without flaking to the metal panels.  The acrylic has not worn away.  The only thing “wrong”  is……the appearance is unattractive. 

A simple coating of acrylic would freshen the appearance to its original luster.

Update:  Formulas now available that resists the chalking

During our first ten years of saving old metal roofing, we performed about five or six green colored projects, after strongly stating that the coating will appear faded or chalked long before most other colors.

Since the release of a formula that preserves organic tints, such as green, it seems many projects now use the traditional green tint. A slight exaggeration in the number……the point is….green stays green.

applied by Roof Menders, Inc, of Conshohocken, PA
610-941-1051
Over 150 tin roofing mini-articles
(In PA, R.Menders Inc )
(c) Copyright 2014

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