You didn't say what material you are replacing and how long it lasted. 
Is there any need to be concerned with in-kind replacement?  In the 
right conditions, I think you might get nearly as many years out of the 
other two (50 yrs. for yellow, you said) so you might want to consider 
cost/longevity although installation is going to be a fairly high 
percentage that, if need twice as often e.g. over another product, would 
make a big difference.

Something else to think about possibly is what happens to the appearance 
do to weathering.  Different types are suppose to weather to different 
hues (although I believe some feel it has more to do with environment 
than material).  Will it matter that your project is visually different 
than the rest of the lot(s)?

Sign me,
Weathering to a silver gray (prematurely)

[log in to unmask] wrote:

>  
> The Histo Presto people on Nantucket may have good information on this.    
>  
> Ralph

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