# How much does moss growth affect roof life span? **URL:** \ **Category:** Exterior Inspections\ **Created:** [July 30, 2007, 3:40pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884 "2007-07-30T15:40:13Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![fbartlo](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/fbartlo/32/57038_2.png) [@fbartlo](https://forum.nachi.org/u/fbartlo)\ **Post date:** [July 30, 2007, 3:40pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/1 "2007-07-30T15:40:13Z")
I frequently find roofs that are relatively new, but have a considerable amount of moss growth, typically if there are tall trees near the house. It stands to reason that the roots of moss and similar plants would cause some breakdown of shingles, but to what degree? Any info would be much appreciated for a current report Iā€™m working on and for future reference. ---
**Author:** ![mlarson](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mlarson/32/89225_2.png) [@mlarson](https://forum.nachi.org/u/mlarson)\ **Post date:** [July 30, 2007, 4:00pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/2 "2007-07-30T16:00:51Z")
From the manufacturer of [Z-stop](http://www.z-stop.com/faq.htm) **Why remove moss or fungus at all?** Moss can severely damage, even destroy, a roof, by breaking down the fibers in the shingles, forcing them apart and allowing leaks to occur. Many roofs must be replaced prematurely due to damage caused by moss that has been neglected. Fungus, algae and mildew are less damaging to a roof than moss, in terms of actual destruction. However, it looks _terrible_: the roof on most houses is one of the largest visible surfaces, and when it is covered with fungus, algae or mildew, it detracts from the appearance of the whole house. Another reason is that fungus reduces the ability of the roof to reflect away light and heat, thus making for _higher air conditioning bills_. ---
**Author:** ![rcooke](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/rcooke/32/57038_2.png) [@rcooke](https://forum.nachi.org/u/rcooke)\ **Post date:** [July 30, 2007, 4:35pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/3 "2007-07-30T16:35:40Z")
I understand removing Moss does damage the roof . The Zinc strip mentioned above will kill moss and I do recommend it in Damp shaded locations all the time . Even using a pressure washer is not recommended. Cookie Added.[http://www.inspect-ny.com/roof/ShingleMoss.htm#bannertop](http://www.inspect-ny.com/roof/ShingleMoss.htm#bannertop) ---
**Author:** ![lkage](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/lkage/32/347658_2.png) [@lkage](https://forum.nachi.org/u/lkage)\ **Post date:** [July 30, 2007, 6:02pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/4 "2007-07-30T18:02:08Z")
A stiff broom seems to work well if one gets to it before the moss is too dense. šŸ˜‰ ---
**Author:** ![mlarson](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mlarson/32/89225_2.png) [@mlarson](https://forum.nachi.org/u/mlarson)\ **Post date:** [July 30, 2007, 8:30pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/5 "2007-07-30T20:30:19Z")
> [@lkage](#): > > A stiff broom seems to work well if one gets to it before the moss is too dense. šŸ˜‰ It will return unless a zinc strip is added near top or the local microevironment chages.(More sun, less dampness, etc.) ---
**Author:** ![lkage](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/lkage/32/347658_2.png) [@lkage](https://forum.nachi.org/u/lkage)\ **Post date:** [July 30, 2007, 9:13pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/6 "2007-07-30T21:13:35Z")
dbl post ---
**Author:** ![lkage](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/lkage/32/347658_2.png) [@lkage](https://forum.nachi.org/u/lkage)\ **Post date:** [July 30, 2007, 9:14pm UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/7 "2007-07-30T21:14:04Z")
> [@mlarson](#): > > It will return unless a zinc strip is added near top or the local microevironment chages.(More sun, less dampness, etc.) Well, yes, trimming back the trees/shrubs (recommended) helps to make it more permanent. šŸ˜‰ ---
**Author:** ![kshepard](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/kshepard/32/59504_2.png) [@kshepard](https://forum.nachi.org/u/kshepard)\ **Post date:** [August 1, 2007, 5:37am UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/8 "2007-08-01T05:37:49Z")
Does it damage by holding moisture against the roof which results in freeze damage, or is it actually root growth doing the damage? ---
**Author:** ![kshepard](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/kshepard/32/59504_2.png) [@kshepard](https://forum.nachi.org/u/kshepard)\ **Post date:** [August 1, 2007, 5:44am UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/9 "2007-08-01T05:44:35Z")
[This](http://dmr-gutters.com/rf/moss.htm#composite)looks like pretty good information. ---
**Author:** ![Brian\_A.MacNeish](https://avatars.discourse-cdn.com/v4/letter/b/90db22/32.png) [@Brian\_A.MacNeish](https://forum.nachi.org/u/Brian_A.MacNeish)\ **Post date:** [August 1, 2007, 9:31am UTC](https://forum.nachi.org/t/how-much-does-moss-growth-affect-roof-life-span/18884/10 "2007-08-01T09:31:21Z")
Some good info there, Kenton, but these guys should get their taxonomy knowledge updated. Moss is not a fungus but has its own division- Bryophytes- within the plant kingdom. But this is just one of the plant types that grow on roofs; others are lichens, fungi and algae. I have also seen small trees sprouting on both roofs and in gutters.