Just something for everyone to thing about - was reviewing the below e-mail about sealing up the attic space in a home in Hot, humid climates.
I grew up in the Carribean Islands, where many homes, even today, are not centrally air conditioned, or for that matter, air conditioned at all. Matter of fact, the house I grew up in had no AC.
Basic principles for home building, seen in many of the old buildings there, and still visible today in places like Key West included:
- Never build an east-west facing house. This was for two reasons - as little window exposure to the sun as possible, and because north/south exposure allowed the prevailing trade winds to vent through the house.
- "Fretwork" or open slats above the windows and doors, so that even when those were closed, air could still circulate through the cielings of the house. Some of these slates are very decorative, hence the name "fretwork".
- Porches or awnings outside of the windows and doors so that as little direct sunlight as possible hit on them
- Ceilings between the rooms and the roofs, to create an insulating barrier of air. This space was also vented by fretwork, athough there are very few "attic" spaces as this created a large space to trap heat & provide a home to insects & vermin.
- Enough of a peak on the roofs to allow the torrential rains to run off, but not so high that a heat trap was created.
To my point about Hurricanes - the oldtimers in the islands also insist that during a hurricane, a vented house can "breathe" allowing the pressure between the air in the house and that outside to equalize, and thus preventing it from being stressed by the air pressure difference. They say that you might get things wet inside the house, but probably not so badly that you can't dry them off, and be much better off than if you have lost your house entirely to the hurricane.
This presumes, of course, that storm surge and flooding like that seen in the Gulf Coast in this last year is not going to be an issue.
From: Nan Hildreth
Sent: Apr 8, 2006 12:53 PM
Subject: Re: [hreg] Building Science Corp.
If the radiant barrier was stapled top to bottom, instead of side to side, I would think it would be eaiser to install.
At 12:47 PM 4/8/2006, you wrote:
Hello Nan, The radiant barrier is stapled to the under-side of ALL of the roof rafters in my attic and my roof has a very low angle 4/12 pitch. The heavy duty double-sided foil with nylon webbing between it (makes it stronger to staple) came in a 48" wide by 125' long roll. Starting from one side of the attic, stapling a starting point, then stretching tight the foil and staple to each rafter as you move along. Crawling in an attic is bad enough, laying on your back amongst the insulation, cutting around blocking vents etc. was quite the contortionist way of doing things. As far as sealing the attic those were all of the new designs when building a new home. Existing houses like mine could in no way be sealed up there are too many holes/leaks and vents already there. Summer in Houston is responsible for the direct radiation heat build up, i am hoping to reflectively reduce that amount with this barrier. My furnace is in the attic also, I hope to check for leaks in the ductwork, improve insulation depth and last but not least make some needed connections between roof and walls for wind safety (Hurricane?). The weather this weekend is absolutely wonderful compared to last week. Bill
Nan Hildreth <nanhildreth@...> wrote:
- Why did the radiant barrier take so long?
- In my houses, the gas furnace is in the attic, so I don't want to
- seal the attic.
- At 08:30 AM 4/7/2006, you wrote:
- >Hello all,
- > After research and spending WAY too much time in the attic
- >last weekend installing my radiant barrier I found this web site. As
- >it applies to new construction in a "Hot-Humid Climate" I have found
- >it does make sense. Although my 35-year-old home is an energy hog I am
- >still puzzled about what the best solution may be. Talked to a green
- >Architect who did NOT suggest "power-ventilating" attic space. But
- >here's where my catch is. New technology suggests sealing attic space
- >w/no venting, keeping AC ductwork leak-proof OR inside the conditioned
- >space! Ceiling is also sealed. All of this has to do with air
- >pressure, vented attic spaces it seems have "negative pressure" while
- >sealed has "positive". Air dynamics is a tricky one at the very least.
- >So, I am back to reading and figuring the best way to handle my Homes
- >heat build-up. These sites have alot of info. When
- >comparing "Benchmark" home to "prototype" and then to "Advanced
- >Technology" home is quite amazing.
- > http://www.buildingscience.com/designsthatwork/hothumid/DTW_HotHumid.pd
- >My best to all- Bill Stange
- >Yahoo! Groups Links
- Nan Hildreth, Houston
- 713-842-6643 NanHildreth@...
- 713-443-3104 cell
- 3939 Luca St.
- Houston, Tx 77021
YAHOO! GROUPS LINKS
Nan Hildreth, Houston
3939 Luca St.
Houston, Tx 77021