Re: How you design an off-grid home to deal with extreme heat

[elnav]

No ductwork? No DC refrigerators?

Although it may be too late to cope with the present heat wave, several things can be done in short order. Homes in hot climates tend to have white or reflective exterior surfaces. Lots of insulation is good, more is better. Yes it sounds counter-intuitive but consider this. You can cool off partially at night then keep heat from invading living quarters during the day. Even something as simple as shiny aluminum foil can be a radiant heat barrier. Reflectix is a bubble wrap product coated one side with silver foil. It is often used in attics to reflect the radiant heat from dark roofing tiles back up instead of down to living quarters. In the longer run consider installing light or even white or silver colored roofing materials as oposed to darker colors.

Duct work is not that expensive. It can be retro fitted in attic or under floor or in basements. Worst case it can be run on shady side of house. Granted it may not look great but its a choice of comfort or appearance.

Even something as basic as hanging up towels soaking wet to give some cooling as water evaporates will provide some relief. Fans will speed up this process even in humid climes.

Yes I am aware swamp coolers are not as effective in coastal area compared to desert climates. But it does work.

While working on survey crews in blazing summer heat I learned to wear long sleeved white shirts and a hat. Soaking the collar and sleeve cuffs and the hat gave me some relief even on hot humid days. Better than heat stroke any day.

If I was building from scratch I would put R40 insulation in walls and ceiling. Exterior siding would be a white color. The roof would be the new metal sheeting in a silver color. If house was built on a slab I would place a large trunk duct on slab then tee off to various rooms. The slab being in shade and in contact with ground would be the coolest place in house on a hot summer day. It would help cool the trunk duct.

When I built a house in the Great Lakes region I designed ducting for central air conditioning but discovered I did not need it. Just fans.

If DC power is all you have either get a small inverter to power an icemaker or buy a DC refrigerator. You can blow a fan across a bowl of ice cubes for an effective cooler. More elaborate setups are also possible given some DIY skills.