Updated: Mar 31, 2020
Alternative Housing post 2010 Earthquake
TI KAY PAY-HAITI SMALL HOUSE OF STRAW
Using Local Materials and Developing Local Industries (click image for blog)
The Ti Kay Pay model home was designed to use as many in-country and local materials as possible, to build on existing labor and skill resources, and to encourage the creation of local industry. From the foundation to the roof, material and building system choices were made with these goals in mind. One material resource that was largely untapped in Haiti is the rubble resulting from the collapsed buildings in the earthquake. The Ti Kay Pay design uses crushed rubble for the foundation footing and gravel bag stem walls. The same material is also screened for fine aggregate in the plasters. Cut and sewn to the needed size by a local seamstress, these gravel bags are made from the ubiquitous tarps that are found throughout the earthquake affected region.
Straw bales are central to the Ti Kay Pay construction system. Rice straw is plentiful in Haiti, as rice is commonly grown in the broad Artibonite Valley northwest of Port-au-Prince. At least 80% of rice straw in Haiti goes to waste, usually burned after harvest, polluting the air in the process. Two to three rice crops are grown annually, making straw a rapidly renewable resource in Haiti. The Ti Kay Pay uses manually baled straw, for its wall system, reinforced with bamboo and covered with interior clay and exterior lime plasters. Clay is readily found throughout Haiti and a tradition of clay plaster exists. Pallet or bamboo trusses provide the roof structure, covered with commonly available and durable sheets of corrugated steel. Wood from pallets, left from the vast number of post-earthquake aid shipments, has become a new in-country resource for Haiti. Bamboo has long been native to Haiti, and a number of bamboo plantations existed before the earthquake. However, it is now widely seen that strong and fast-growing bamboo has been underutilized as a construction material in Haiti over recent decades.
Although the thermal insulation commonly associated with strawbale buildings is generally not needed for interior warmth, the system’s excellent balance of mass and insulation moderate temperature to keep interior space cool. A light mix of straw and clay is used as insulation above the ceiling to protect from the heat of the sun as it warms the roof during the day. The attic space is generously ventilated, and louvered transoms above doors and windows provide cross ventilation throughout the day.
The Ti Kay Pay is a culturally appropriate design derived from the Haitian Ti Kay, a two-room shotgun layout with veranda style house, which is the typical rural and sub-urban living unit in Haiti. The veranda is especially important to the design, since much of Haitian daily living occurs outside. It provides an outdoor space protected from sun and rain and serves as a transition from the more public yard or street to the private interior rooms. The design is a blend of traditional and modern in its form and appearance, including the plaster finishes associated with the modern concrete and block buildings Haitians have come to prefer, but with a light roof that so many Haitians are returning to after countless concrete roofs collapsed in the earthquake. The system of strawbale construction developed for the Ti Kay Pay can also be applied to other house designs, or other building types as well. It is particularly suitable for use in small schools or clinics. Larger scale buildings, including two story buildings, could employ many of the systems developed for the Ti Kay Pay with proper engineering.