Homes can take advantage of natural processes to keep it cool, insulated and comfortable all year round. We have been so dependent on insulating our homes, wrapping it in plastic, and then spending our hard earned money on HVAC to keep it as close to 75deg as we can afford that season. Here in Texas, heat is more of a problem than cold for most of the year-and I’d like to capitalize on the prevailing wind to cool my home-especially if I want to not be dependent on the grid so much.
I have a consistent breeze here in Texas in my backyard. I wish I could let that breeze go through the entire house-but my current home does not really allow that. I sit in my near window-less home office cranking at work and dependent on my HVAC to recirculate me the temperature controlled air.
That fresh breeze out there is a great resource, it is free, it is cleaner and much more rejuvenating than anything I can get out of my HVAC. I wanted to capture that energy and use it inside my home, reduce my energy costs and improve my quality of life.
I’ve designed my concept home to optimize the use of the predominant wind in my area. I think all homes should do this, however just like most homes today disregard solar orientation, they also don’t design it to capture the breeze. Architects today tend to not think about these resources and miss the blessing and advantage from it.
The concept home is oriented to catch the prevailing wind. The plan itself is shaped to scoop and funnel as much of the breeze as it can so that it can be brought into the interior. The windows are laid out to cross ventilate the main living spaces and bedrooms. In this image, the breeze come from the left (which is the south on the site) and takes the trapped warm air out to the right.
The attic space is designed with increased ventilation in mind. Attic ventilation is already required by building code, however since it is codified, most of the time designers and builders provide the minimum to meet the requirement. That’s usually why most homes have energy loss in the roof/attic space. To explain this venting logic, imagine you are camping in a tent under the sun during summer – that tent can still be warm. Now imagine you hung a tarp over that tent (or camped in the shade of a tree)-you now have the shade plus the airflow inbetween the tarp and tent to allow you a more comfortable environment. This logic is easy to grasp, but having codified it makes us miss the benefits we can leverage.
Another interesting part of the design is the ceiling and roof work together as a solar chimney. I have a ceiling that will be shaped to be higher than the rest of the ceiling. It will be located where warm air is likely to get trapped in the interior – due to where the source of the wind is. On the outside, the roof for this area of the ceiling will have less venting, possible allowed to be warmer than the rest of the roof. This can be thru collecting more heat from the sun by using a darker colored roofing, or may have less insulation or less attic air flow. This part of the roof is designed to get warmer.
Being warmer, this will attract the warmest temps in the ceiling and trap it there. Once trapped, this warm air will be allowed to escape thru dormer windows/louvers. Think of how the Roman cities would use structure as solar chimneys for their plazas-this is a similar concept except it is scaled down to the interiors of a home.
Important to note, this will need casement windows on the windward side. I can use single hung windows on the leeward side. This is because I expect more air volume on the supply (windward) and can work with less on the exhaust (leeward). Bug screens will be required.
With these design techniques, my homestead would need less energy to keep it comfortable in the Texas summers. This means less expense for my utility bills, or a smaller solar panel array and less battery storage.
My goal at Alt-Ark is to Make Homes More Permaculture, to help you build that permaculture home on the homestead.