Re: Couple issues
Never heard of "skin venting" but sounds awefully close to what I'm thinking.
Originally posted by perpetual_student
Are you familiar with the type of wall construction known as "skin venting" or "vent skinning"?
So, does this resemble your idea or not so much?
As far as I know there are not any undiscovered water leaks or other abnormalities to account for this.
Do ya think your undiscovered water leak is actually the water sitting in your toilet? hehe
Think about it... its bound to evaporate since its sitting there all day long.
Do a test and turn the water off to your toilet and flush the water out so its all dry. Keep an eye on it and see if your RH goes down.
This is of course if your wife don't mind hehe.
People speaking of these radical house designs and stuff.... I fell in love with Dome homes there for a long time. Did some work on a unit at one and the lady give me a grand tour. It was a true work of art.
Hmmm... all the puzzle peices are making full circle.
I remember one design that had the return air grille way up high on the second floor. They hiped it up like it was supposed to circulate the air better. Though that part might be true, but it seems if the air entering the A/C coil is warmer than normal.... you end up raising the surface temp of the coil. Which in turn could raise it above the Dew Point(or at least a portion of the coil since the refrigerant would boil off faster. This might be countered by using a TXV though.)
In turn reducing its ability to remove moisture.
Hot Return Air = Warmer Evap = Coil temp above Dew Point = Lack of humidity removal
The idea in the original post about
a dedicated duct pulling air from upstairs and redistributing downstairs sounds like a good way to keep the air evened out. I just wouldnt' want that to be a return for the air cond system.
Old dude that taught my Manual J class in Tyler, TX did it in a Cape Cod via an abandoned multilevel fireplace. It worked very well! Warm air from ceiling of second level sent to floor of first level in winter. Cool air from floor of first level sent to ceiling of second level in summer. Fan was used to overcome the natural stratification of the home. Sure was a lot cheaper to install a few feet of insulated duct and a reversible fan than a zoning system and its dampers.
Originally posted by chillbilly
Yes, and a reversible fan motor to switch for each season would be effective but duct sizing would still be a factor.
Once upon a time, I had a house with one 6,000 BTU windowbanger in a bedroom. It didn't cool the rest of the house, but did keep the humidity down enough to make it tolerable through the entire house.
Your bathroom has water on the shower walls, water in towels, water on the sink, at least one wet bar of soap, and water in the toilet. It has water in the shower and sink P-traps. All of those are adding water to the air. You might check bathroom humidity with the door open versus closed. Also before and after taking a shower.
That's why my house has the HRV taking air from both bathrooms (35 CFM total on low, 24 hours per day), and discharging the makeup air into the ductwork. No heating ducts into the bathroom, so all the humid air goes straight outside. We have a pushbutton to switch the HRV to high (140 CFM), but haven't seen a need to use it. With airtight construction and R-30 outside walls, the bathrooms are the same temperature as the rest of the house.
You would need a cave the size of a foot ball field in order to draw cool air from in order to satisfy the demand from the attic.
Plus, without a radient barrier upstairs, this cool air would shortly become hot itself.
Do some research on Frank Loyd Wright. He built a home on the Arizona desert which was half buried into the hillside<<<<
I once serviced a home when I first started in this business
that sat on a bluff overlooking Lake Erie.
It had a shaft the size of a commericial elevator sunk into bluff that opened up somewhere near the surface of the Lake.
It was used to draw cool air off of the water at certain times of the year and sent throughout the house
Over time the shaft collapsed, but the thing I remembered most was literally walking into the filter/return air box to change the filters in this mansion
That was back when we used 2 inch fiberglass pads for filters..... you want to talk about itching after changing those over the course of a day
Drawing air from under house....
Guess I should state that the intent was not to satisfy
the load of the attic... merely lower the temp a little
more as compared to drawing the air from the soffit vents.
At the same time.... providing mechanical ventilation
for both the attic and crawlspace using just the exhaust fans in the attic. Two birds with one stone. You can also add providing ventilation for the
dead air space between the brick wall and stud wall.
So now you got 3 birds with one stone
Keep in mind this is all just pass time wondering.
I wouldnt' wanna do it in my on home (if I ever am
able to build one hehe)
I'm kinda stuck on the fence when it comes to wether or
not to ventilate the attic and crawlspace when it comes down to it.
There seems to be alot of good info that says
its best not to have any ventilation.
Skin venting wall construction
Wormy, you probably will be interested in this:
The method is variously called "skin vent" or "vent skin" construction. You can use a Google search with the keywords 'house "vent skin" wall' or 'house "skin vent" wall'. Ignore the false hits on reptiles <g>. I think people from the Florida Solar Energy Center are acquainted with it, but I have not seen any publications measuring results.
It describes formally a type of wall construction which apparently has been used for a long time in warmer climates. This looks like your description in about half of its qualities, the other half look different. Usually it is a combination of radiant barrier in east and west walls, and making sure the air has a clear and free path to move upward via stack effect. Proponents claim this is a superior way to ventilate attic space, keep walls dry, and prevent heat buildup in walls.
I have learned of this method used by several builders and architects in the Houston area. One of the published references I have seen goes back to the 1970's, that is the earliest I have seen in writing. They caution that this will become non-productive if used farther north than a certain number of degree-days for winter weather.
Your thoughts on the toilets as a humidity source are very intelligent and logical. I really admire your proposals to experiment, but I will sorta have to move mountains in order to try this in my family environment. Will keep my eyes open for opportunities to try this and easier experiments.