Democratic Republic of Congo
Bricks for this house are made from a Cinva-Ram press, which compresses a mixture of cement and dirt or clay in a metal box to form bricks. The bricks dry in the shade for about two weeks. Spaces are left above both the interior and exterior walls to improve ventilation.

Average house cost: US$2,545

Papua New Guinea
Due to heavy rains, houses are built on stilts to keep the house dry. The area under the house is used for storage, community gatherings and livestock. Concrete is expensive and not widely used in PNG, so wood is treated to prevent decay and termite infestation.

Average house cost: US$2,304

Sri Lanka
Some areas build with 6-inch hollow concrete blocks with steel rods to help the structure resist earthquakes, plus micro concrete roof tiles. In other places, houses are built with dry stacked interlocking compressed earth blocks on a stone rubble foundation with corrugated roofing sheets. A lime wash on the blocks offers weather resistance. The house design includes a cooking area, gable roof and pour flush toilet.

Average house cost: US$2,436

India
Meals and socializing occur on the porch. The high entry step is believed to keep snakes from entering, and the bars on the windows protect from thieves and monkeys. Houses are built of fired bricks for walls and steel-reinforced concrete roof slabs. Some houses are made with hollow-core concrete blocks and tile roofs.

Average house cost: US$1,793

Romania
The traditional block construction in Romania takes at least a year to build, but wood frame construction is quicker and more energy efficient. Stucco protects the house walls from weathering and locally made clay tiles finish the roof.

Average house cost: US$24,843

Guatemala
Houses made of hollow concrete blocks and steel rods are designed to resist earthquakes. The window coverings and door in this photo are wood; however, metal is used in some areas where wood is more expensive.

Average house cost: US$2,100