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<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><?xml:namespace
prefix = o ns = "urn:schemas-microsoft-com:office:office"
/><o:p> </o:p></SPAN></P>
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style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">I
feel fortunate to live in a location where during the summer, the night time
cools about 30F from the highs.<SPAN style="mso-spacerun: yes"> </SPAN>I
have made a commitment to live without air conditioning here in the mountains of
Virginia.<SPAN style="mso-spacerun: yes"> </SPAN>I have incrementally been
upgrading the tightness of my house, having installed new continuous thermal
barriers of 3” iso foam over most but not all of the exteriors walls and below
cathedral ceiling.<SPAN style="mso-spacerun: yes"> </SPAN>Piece by piece,
I am covering all the holes that remain.<SPAN style="mso-spacerun: yes">
</SPAN><o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">We
are coming into the hot time of year again.<SPAN
style="mso-spacerun: yes"> </SPAN>We have been in the practice of opening
windows at night and aggressively changing the air in the house with window fans
to cool the mass inside the house.<SPAN style="mso-spacerun: yes">
</SPAN>Most days, we can get the house to below 70F.<SPAN
style="mso-spacerun: yes"> </SPAN>We close the house off during the
daytime to block out air delivered heat.<SPAN style="mso-spacerun: yes">
Last year after only the ceilings were complete, we hit our record high of
103F with house at 79F without ac. </SPAN>As part of the Thermal
improvement project, I have installed an HRV.<SPAN
style="mso-spacerun: yes"> </SPAN>We run the HRV during the day to deliver
fresh air when windows are closed to block heat out.<SPAN
style="mso-spacerun: yes"> </SPAN>The peak temperature outdoor air has
much lower relative humidity than indoor air from night flushing.<SPAN
style="mso-spacerun: yes"> </SPAN>I can observe the condensate drain.<SPAN
style="mso-spacerun: yes"> </SPAN>Under normal fair weather days, there is
negligible if any condensation.<SPAN style="mso-spacerun: yes"> </SPAN>My
hunch is that the interior and exterior absolute humidity is about the same, so
cooling the outdoor air closer to the indoor night flushed temperature never
reaches dew point.<SPAN style="mso-spacerun: yes">
</SPAN><o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">However,
night flushing does result in high humidity in the house.<SPAN
style="mso-spacerun: yes"> </SPAN>I have now been observing humidity for
the past year more closely.<SPAN style="mso-spacerun: yes"> </SPAN>The
result of night flushing is to seasonally build up humidity in the house.<SPAN
style="mso-spacerun: yes"> </SPAN>This time of year, the house has some
residual dryness from the heating season.<SPAN style="mso-spacerun: yes">
</SPAN>I think the material of the house is a humidity flywheel as well as a
thermal flywheel.<SPAN style="mso-spacerun: yes"> </SPAN>However, this
material is gradually wetted with increasingly high indoor humidity.<SPAN
style="mso-spacerun: yes"> </SPAN>Late summer, wood work swells and there
is some mold.<SPAN style="mso-spacerun: yes"> </SPAN>This goes away when
it dries out again as heating begins in the fall.<SPAN
style="mso-spacerun: yes"> </SPAN><o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">The
outdoor air, even when entering with a high relative humidity is being warmed up
by the warmer house, reducing the relative humidity.<SPAN
style="mso-spacerun: yes"> </SPAN>However, late summer the house can be in
70% range.<SPAN style="mso-spacerun: yes"> </SPAN>This slows down the rate
of drying for anything in the house.<SPAN style="mso-spacerun: yes">
</SPAN>How much is our health at risk? I presume there is some dust that becomes
air born from mold.<SPAN style="mso-spacerun: yes"> I learned from this
list that floating pathogens do not redily dry up allowing more contagons.
</SPAN>Is this health risk mitigated by fresh air delivered by HRV?<SPAN
style="mso-spacerun: yes"> </SPAN>The higher humidity reduces the
evaporative cooling of our body at a given temperature.<SPAN
style="mso-spacerun: yes"> </SPAN>However, the lower temperature is
definitely more comfortable than the hot outdoor air.<SPAN
style="mso-spacerun: yes"> </SPAN><o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">I
know I am much more comfortable with the strategy of night flushing than I would
be with leaving windows open all the time.<SPAN style="mso-spacerun: yes">
</SPAN>The greatest discomfort comes on the rare occasion where the outdoor
temperature does not get down to 70F.<SPAN style="mso-spacerun: yes">
</SPAN>This greatly reduces the cooling of the house at night.<SPAN
style="mso-spacerun: yes"> </SPAN>When this happens, I use a direct fan to
keep my body comfortable. <o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">Insights
on the impacts of high humidity in the house will be appreciated.<SPAN
style="mso-spacerun: yes"> </SPAN><o:p></o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'"><o:p> </o:p></SPAN></P>
<P style="LINE-HEIGHT: normal; MARGIN: 0in 0in 0pt" class=MsoNormal><SPAN
style="FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 16pt; mso-fareast-font-family: 'Times New Roman'">Eli
<SPAN
style="mso-spacerun: yes"> </SPAN><o:p></o:p></SPAN></P></BODY></HTML>