Humid Tropic Home Designs

Hello,

I’m planning on having a home custom-built in a high rainfall tropical equatorial region of about 1000-2000mm avg annual rainfall and year round temps of 85-90 degrees Fahrenheit.

Can you please recommend some resources to help learn the design features in this environment? It will have to be insect-proofed, and integrated with a compost toilet system.

I don’t plan on teaching myself everything, but I want to learn enough to explain what I want to an architect, and contractor.

I’m interested in traditional jungle house design, but would like it to be a little more “luxurious” and durable.

Bill Mollison's Permaculture a Designers Manual discusses tropical design extensively.  

Windy Huaman wrote:Hello,

I’m planning on having a home...in a high rainfall tropical equatorial region of about 1000-2000mm avg annual rainfall and year round temps of 85-90 degrees Fahrenheit.

Are you planning to be off-grid?

I don't know what sources to suggest, but living in Hawaii with the same amount of annual rain, though lower temperatures, I can tell you what has worked and not worked for us. This list will be in no particular order. It will be just as the thoughts come to my head.

1- air ventilation. We used lots of windows and doors. The air needs to move through every room, thus we have no closed up rooms at all. Note: if you are in a hurricane zone, you may wish to have a central safe room that you can shelter in. This room won't have windows. We don't have one in our house. We have a mini barn suitable for storm shelter if it is needed.

2- bathrooms. Mold will grow everywhere if you don't have a method to dry it quickly. We have a door to the outside, plus windows. And use our outdoor shower much of the time so that we don't need to towel dry the shower stall. An outdoor shower is wonderful. Ours is right outside the bathroom door on the hot tub deck.

3- open interior design. This provides good air flow, plus leaves less surface spaces for molds to grow. We limit the number of bookshelves, bric-à-brac decoratations, little furniture pieces all over.

4- no closed up closets. We opted for a walk in closet that is actually a long narrow room off the bedroom. It has its own window system for air flow. Our friends put closets in their houses but they don't have ceilings, thus they aren't closed up. Closed up spaces grow mold in the tropics unless one uses closet heaters. We are off grid, so closet heaters aren't an option.

5- no closed cabinets in bathrooms and kitchen. This seemed so wrong to me when I moved here, but it's really the best option. I'm fully in support of no cabinets now.

6- no pressed board wood. It disintegrates quickly here. Use only real wood or exterior plywood. We opted to use cedar throughout the interior of the house. Bugs don't like it as much and mold doesn't grow on it. Yes, cedar is imported but it has been worth the price. Other tropical woods can also work but you need to check if they are mold and insect resistant.

7- roof overhangs....a must. They help keep the sun for heating up the house plus more importantly, you can keep the windows open even when it is raining.

8- a roofed over entranceway porch. It doesn't need to be big, but you'll appreciate a spot out of the rain to take off your wet shoes and whatever before going into the house.

9- no wall to wall carpet. And limit your carpets and rugs. They grow mold, attract insects, and are a dang nuisance in the tropics.

10- think about not using drywall/sheetrock. It can grow mold, and it can disintegrate.

11- consider using bamboo or rattan furniture. There's a reason it's popular in the tropics. You can drag it outdoors and hose it off with bleach water to get rid of any mold spores.

12- don't use anything leather. It quickly gets green with mold. No leather chairs and sofas for sure.

13- ceiling fans. If you have the electricity to run them, you really appreciate them.

14- high ceilings. The heat will rise up into the high ceiling, leaving the living area closer to the floor cooler.

15- no skylights. Houses with these tend to be ovens during midday.

16- bleach will be your friend. Wiping surfaces with diluted bleach water will keep your house from smelling like mildew. So have surfaces that are wiping friendly.

17- open wide doorways between rooms. Allows for air flow.

I'm sure there's more suggestions but they just don't come to mind right now,

Oh yeah, I forgot a biggie. Don't build on a slab if you can help it. Build on a pier & block foundation. Slab houses have allow lots more insects and wildlife into the house. Everything that creeps and crawls gets into slab homes.

Su Ba wrote:Oh yeah, I forgot a biggie. Don't build on a slab if you can help it. Build on a pier & block foundation. Slab houses have allow lots more insects and wildlife into the house. Everything that creeps and crawls gets into slab homes.

That is interesting.  I would have thought the opposite.

We built on pier & block on the advice of locals. With slab foundations, ants and centipedes are a daily hassle, and there's no way to block them out. Lizards, geckos, and roaches also have easy access with a slab. Those critters are easier to keep out when building on pier & block. We have pest guards on each of our piers.

Burl Smith wrote:

Windy Huaman wrote:Hello,

I’m planning on having a home...in a high rainfall tropical equatorial region of about 1000-2000mm avg annual rainfall and year round temps of 85-90 degrees Fahrenheit.

Are you planning to be off-grid?

Yes

Su Ba wrote:We built on pier & block on the advice of locals. With slab foundations, ants and centipedes are a daily hassle, and there's no way to block them out. Lizards, geckos, and roaches also have easy access with a slab. Those critters are easier to keep out when building on pier & block. We have pest guards on each of our piers.

Your list is really helpful.
Can you show a picture of what you mean by pier and block?

What do you use for roofing material? I know the traditional way is with fan palm shingles.

Roof......corrugated metal. It is readily available here. Since we catch the rainwater, we needed a roofing material that is suitable for that purpose.

Rather than pulling off the skirting around our house to take photos of the foundation, I captured a photo off the internet instead. Our house is required to be a minimum of 24" above ground level, so 24" long posts vertical are mounted to the blocks and attached to the wood beams. This brings the house a bit more than two foot above ground level.

Su Ba,

Do you have a picture or link for your pest guards for your piers?

Is there a way to basically “wrap” the entire house in insect netting without it looking like an eyesore? I’m not sure how else you can bug proof a home.

I once stayed in a jungle lodge built on 5m tall legs and there were still a lot of bugs in the room, so just raising the home off the ground doesn’t solve that.

Hello Windy,

Perhaps the best picture to visualise is the quintessential British colonial house made for the Pacific Islands, Australian, Papua New Guinea, South Africa, the Caribbean.

My house is a typical 'Queenslander' design (late 19th Century type), which was designed for harsh weather conditions i.e. tropical heat, severe storms (Cyclones), etc. In it's day, timber lattice and canvas blinds were extensively used to shade verandahs.

Some of the old and modern features typically include:

* Louvre and Casement windows with fly-screens
* House on piers to increase airflow underneath the house e.g. >1 metre. This works well for a Compost Toilet - 'The Long Drop'!
* All-round verandahs
* Use of corrugated metal roof sheets with insulation underneath
* Open plan internal layout
* Timber/tiled floors
* Ceiling fans – inside and underneath the verandahs
* Turbine type extraction fans on roof

Landscaping around the house is also critical – depends on the orientation of the house and surrounding site - that is where Permaculture comes into the picture e.g. Sector Analysis, Zones, food forest, vines on trellis/pergolas, etc


I suggest taking a look at this rather comprehensive website about sustainable housing:

SUSTAINABLE HOUSING DESIGN

Very similar conditions here in Brazil. Here are some infos... big porch area, nice drainage and foundation... don’t forget to cover, it rains here several times during the day, we use the tarps and by the end of the day we cover the walls with a plastic sheet too.

https://permies.com/t/111965/Cob-House-Bahia-Brazil#974172