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<div class="moz-cite-prefix">On 10/12/2013 11:09 AM, Gennaro
Brooks-Church - Eco Brooklyn wrote:<br>
</div>
<blockquote
cite="mid:CAPV9BxN7Syse1ygBcTqJV0pbb0LXuVBh5NLEa+pjjusXBZxSUQ@mail.gmail.com"
type="cite">The wood will decompose and shrink in depth, requiring
the addition of more. Each time you do that the weight increases.
Is that a valid concern?<span></span><br>
</blockquote>
<br>
No, it's not. Wood is mostly C<small><small>5</small></small>H<small><small>10</small></small>O<small>5</small>,
when it decomposes it does so into things like H<small><small>2</small></small>0,
C0<small><small>2</small></small>, etc. All of those things
subsequently leave a roof environment. So decomposition, and
shrinking in depth, reduce the weight in direct proportion to the
loss in height. Compaction does not however, so I would make your
load calculations based on a fully compacted mass of the given
depth.<br>
<br>
Thank You Kindly,<br>
<br>
Topher Belknap<br>
<pre class="moz-signature" cols="72">--
Topher Belknap
Green Fret Consulting
Kermit didn't know the half of it...
<a class="moz-txt-link-freetext" href="http://www.GreenFret.com/">http://www.GreenFret.com/</a>
<a class="moz-txt-link-abbreviated" href="mailto:topher@greenfret.com">topher@greenfret.com</a>
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