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AJ Rosales AIA LEED AP NCARB
Architecture Planning Design

AJ Rosales

AIA
LEED AP
NCARB


Architecture
Planning
Design

MEXICO: SELF-BUILT HOUSING IN QUERÉTARO
PART A: RESEARCH / HISTORIOGRAPHICAL DOCUMENTATION

Part A Index :
Local History : Heritage / Culture / Tradition : Ecosystem / Climate Change : Existing Housing / Housing Diversity : Typologies : Quality : Programmatic Elements : Timeline of Self-Built Housing in Mexico

Local History:
The state of Querétaro is rich in culture and diverse in its history. Despite being one of Mexico’s smallest states, the region is home to industrial complexes that produce metal goods, machinery, chemicals and processed foods, farms that breed livestock and dairy cows, and cash crops such as beans, cabbage, alfalfa, onions, lettuce and sorghum. Rich mineral deposits also run through the state’s mountains and valleys, yielding silver, iron, copper and mercury.

The Spaniards considered the city of Querétaro to be a critical seat of power and dubbed it “third city of the kingdom.” After gaining independence from Spain in 1821, the city of Santiago de Querétaro became the temporary capital of Mexico, where revolutionaries first declared their independence. In 1917, a constitutional convention was called and Queretaro finally became a unified state. Today, half of the state’s population is located in Santiago de Querétaro, which has an approximately 4% rate of population growth.2

Heritage / Culture / Tradition:
Historians believe that the earliest Querétaro inhabitants were probably the Otomí, a sophisticated society that subsisted on agriculture and livestock, spinning, weaving and pottery. Today the state remains vibrant with cultural heritage. There are indigenous communities in seven of the 18 municipalities of the state, mostly Otomí and Pame. The trading of goods is still an important part of the economy and many residents who live in rural areas can still be seen in traditional dress. The population of the state is sparse in most areas, concentrated in only one true urban center and some smaller communities.

A number of landmarks also exist in the region. The capital city of Santiago de Querétaro is known for its 74-arched aqueduct built in the early 1700s. The third-largest monolith in the world, La Peña de Bernal,. Is located in the city of San Sebastián Bernal. An important archaeological site at El Cerrito also contains the pyramid of El Pueblito.

Ecosystem / Climate change:
The state’s name is derived from Queréndaro, a Tarascan word for “place of the crags,” which probably refers to the area’s mountains. Located in the north-central area of Mexico, it contains 18 different ecosystems due to a varied topography. El Semidesierto Queretano (Querétaro Semidesert) is a wide strip that crosses the state from east to west, generally subdividing the climate it into wetter, mountainous and more temperate zones in the northeast and southwest.19 The area is also seismic and quakes are not uncommon. The center and west have drier and hotter climates, where the Sierra Madre Oriental and parts of the Trans Mexican Volcanic Belt impede moist air from arriving. This dry area includes the municipality of Querétaro.

Ecologically, Mexico as a country has pledged to cut carbon emissions 25 percent by 203018, addressing water / air pollution, waste, and sustainable energy as key factors. Water pollution is of concern in many areas, with filtration systems needed to remove arsenic and fluoride. In the northeast part of Querétaro, the grassroots alliance Grupo Ecológico Sierra Gorda helps to monitor the Biosphere Reserve and encourages conservation. A carbon sequestration program provides land-holders with incentives to re-establish native pine forest on over-grazed and eroding plots. As a whole, the government appears to recognize the responsibility of encouraging sustainable practices.

Mexico is the 12th largest greenhouse gas emitter in the world, and the second largest in Latin America.3 The country is already experiencing longer and hotter periods, more droughts, more intense rains and hurricanes, and frequent floods and mudslides. If climate change is not addressed, the Mexican economy is expected to decline by between 3.5 and 4 percent and suffer significant costs of up to 6.2 percent of GDP.3 Environmental change will continue to have negative effects on poorer and, in particular, on indigenous groups, who depend on sources of income threatened by the effects of climate change.

Mexico Housing 1
Mexico Housing 2

Existing housing / Housing diversity:
Mexico has a higher homeownership rate than the United States.14 Existing housing varies from informal settlements to formal developments. It broadly ranges from single room structures to multi-level multi-occupant divided structures, and larger single-family homes. The majority of it is comprised of some type of fire-resistive construction, as well as party wall separations, however, much of the self-built typology does not conform to any stringent standard.

Typologies:
Because of the individualized nature of self-built housing in Mexico, it is difficult to pinpoint standardized trends (other than the predominance of certain building materials). Self-built housing suits the needs and possibilities of each family, both through their form and phased building which makes each house unique.17 Many families prioritize economy over sound construction techniques, and many structures appear to consolidate programmatic requirements into non-compartmentalized rooms. When additional functions are required, smaller, adjoining, or detached rooms are constructed. Many self-built houses start off as simple one or two room structures, and then become aggregated in irregular configurations as needs develop.

The inherent configuration of each house is driven by personal expression, with each residence taking on a unique formation. This has advantages and disadvantages, in that while the buildings may appear to conform functionally to the user desires (instilling a sense of pride and accomplishment), that the homes lack a sensibility of order. This dichotomy is one that needs to be addressed so that individuals remain invested in their homes yet build towards a future that is sustainable and prudent.

There have been several attempts at creating prototypical housing for low income residents, many being previously sponsored by INFONAVIT. While many of these previous ideas do not hold a completely modern relevance, there is an interesting disclosure inside many of the plans which underlies the simplicity of an ideal which we should strive to attain. These plans are by no means ostentatious or elaborate, nor are they hard to understand or to construct.

Quality:
In terms of low income housing in Querétaro, there are four discernable levels of quality, each one could be considered slightly better than the previous level, and all of the levels would be considered below a more developed or standardized building typology. Quite frequently, the development of a home is inherited through subsequent generations, and through this process, most self-built homes pass through one or more of the following stages:

Level 1: Waste Materials, Cardboard Sheets, Reed / Bamboo, Palm, Mud
Level 2: Metals, Asbestos Sheets, Wood Sheets, Adobe.
Level 3: Unfinished Brick / Concrete Masonry / Concrete Frame
Level 4: Masonry / Concrete Frame with Finished Exterior (Concrete / Paint)

Mexico Housing 3

Programmatic elements:
The following list of existing “typical” program elements for a low-income Mexican household is based on our discussions and observation, and research. It is not a synthesis of the information, but an attempt at categorizing basic wants and needs.

Sleeping zones
- One bedroom or area for sleeping is not unusual, often with a bunkbed and dresser.10
- Many houses contain more than one family, often with more than three persons per room. Overcrowding is an issue with many current families.
- Remote or additional “spaces” for family members are sometimes constructed.

Bathroom / Toilet zone
- When provided, bathrooms are not always fully separated from other living quarters, and when they are, they are sometimes used as bedrooms.
- Approximately 12% of Mexican households have no bathrooms or toilets.5

Kitchen (Indoor or Outdoor)
- Kitchens are not always detached from other living areas, sometimes being located in the same room as beds or sleeping areas.
- Cooking Zone with Gas Tank / Stove or Fire burning Stove.10
- Counter
- Basin
- Small Eating Area on Floor or Table
- Refrigerator not always provided - some occupants shop for food daily.

Utilities
- Potable Water Storage Tank - most houses have a “tinaco” (storage tank) on the roof, because of water supply issues. Water is usually delivered if not available.11
- Approximately 3-9% of Mexican households have no drinking water.5, 21
- Approximately 60% of dwelling units occupied by indigenous people do not have potable or piped water.12
- Approximately 11% of Mexican households have no access to electricity.5
- Utilities are frequently not accounted for in the construction of self-built homes. Some areas are populated by squatting in the hopes that the infrastructure will be provided once the community grows large enough.

Additional programmatic elements
- Commercial Space - some homes contain a small commercial zone at the street
- Outdoor space for living - many homes contain informal outdoor zones
- Parking Space for a vehicle

Timeline of self-built housing in Mexico:
Over the course of the 20th Century In Mexico, concrete blocks have become the dominant building material because they facilitate incremental construction. Another important factor in their dominance far as construction materials is their weight, integrating tepetzil stone as an aggregate. Lightweight block is a cheap material, and the economy of their use makes them preferable over traditional brick construction. Today, the affordability and integration of concrete frames has also become an important aspect of housing construction. Despite the proliferation of concrete frame and block construction, the reality of economics does not always allow a uniform materiality. Quite often, self-built construction has a varied and opportunistic methodology.


The following timeline could be considered a rough outline of the predominance of concrete block construction in self-build methodology in the region:



Pre-1880 / Traditional building techniques: Mud + Straw housing / Adobe Construction / Stone + Mortar / Lime Plaster Facing

1880: Portland Cement begins to provide the impetus for concrete block construction in Mexico.6

1920: Cement and concrete block structures begin to become a symbol of modernity in Mexico.

1930: Government sponsored building and construction in concrete sets a standard in Mexico.

1947: 2.3% of houses in Mexico are self-built.7

1952: 22% of the houses in Mexico are self-built.7

1970: Lighter aggregates in concrete block help diffuse block construction throughout Mexico and the predominant type of housing becomes self-built. (60% of the housing in Mexico City is self-built.)

1976: Mexico implements precast concrete construction standards.

1980: Concrete quality control is implemented in 24 cities, with development initiatives.8

1980’s: The majority of self-built growth occurs in medium sized cities.

1990’s: Cemex and Apasco construction manuals explaining the autoconstrucción process are disseminated to low-income residents, demonstrating technical details important to construction, and best practices, including an emphasis on personal spaces that contribute to family “harmony”.4

2000’s: Proliferation of assisted self-built housing (through developers).

2008: Almost 70% of houses are comprised of concrete block construction.9

PART B: SOCIAL ANALYSIS, MAPPING AND DIAGNOSIS

Part B Index :
Location and characteristics of housing demand : Correlating Factors : Diagrams / Analysis

Location and characteristics of housing demand:
The city of Queretaro has formed an irregular but compressed “incorporated zone” that has aggregated over the course of time. Beyond the city’s edges, the outskirts are peppered with smaller, more isolated areas of housing, farming, and industrial communities. While the siting of many of these communities appears to be based on a somewhat opportunistic approach, it is no surprise that the supporting communities of the industrialized zones have access to richer amenities than the rural dwellings. Both of these locales contain piecemeal self-built housing comprised of the typical bloque de concreto and castillo construction. Each piece of construction reflects the ideal of its constituent owner and their preferences, with myriad variations on housing themes.

One theme that seems to be important to the initial stages of construction is the concept of privacy and perhaps security, with many of the houses starting off as compartmentalized, walled-off enclosures that become infilled. Over time, these separated plots are divested in chunks and eventually become joined, creating the dense urban fabric that Mexico is known for. It is unclear how many of these houses have access to adequate infrastructure, but indeed, some communities build without water or electricity, acquiescing to the land with an advantageous mindset.

Self-built housing has an aesthetic that is also rooted in economy. The ease of assembly and access to masonry seems to override other building techniques. At its most basic level, the exposed use of these materials (frequently integrated into a concrete framing structure) provides an aesthetic of utility, with a variety of material patterns being used to create a more pleasing facade. It is rare to see a finish coat of concrete, and many structures are painted in their raw form to provide a manner of color as expression. In poorer areas, there is a tendency to use rubble for construction, especially for defining lots, and the level of quality varies from slipshod to a somewhat crudely mortared look.

The demand for housing is linked in an obvious way to economic circumstances, but it is also linked to locations with ease of access to amenities. In locations that are distant or lack infrastructure or amenities, it becomes difficult to economically justify growth in those areas. This explains the tendency towards the compressed aggregated urban fabric that exists in the capital.

Correlating Factors:

Mobility
Opportunity, as previously mentioned, is linked to access to amenities. The typical Mexican household has access to a vehicle, but if schools, stores, and supplies are not located within a reasonable distance, it becomes difficult to justify the construction. The variety of amenities is also important to the success of development. Lack of commercial development can be seen as an issue when land is distributed and developed, with housing taking a priority due to need. Ideally, the mobility and social aspects of Mexican culture would lend themselves to a diverse integration of residential, commercial, and public uses.

Socio-Cultural Aspects
Mexican households tend to have a frugal approach towards the use of space. Single-room structures are not uncommon, shared by multiple functions and family members. However, there has also been discussion of the need for multiple spaces within homes, as a more “healthy” approach towards living. Single room structures often have problematic features, such as lack of privacy, and additionally, lack of ventilation, which is especially unhealthy for poorer households.

Mexico Housing 4

Correlating Factors (continued):

Regulations
The Mexico City Building Code is, in fact, used as a model code elsewhere in Mexico, but there is no official National Model Code. Even though great importance is given to seismic design, discrepancies interpreting the code exist in local jurisdictions. Energy codes are, at times not fully adopted by local authorities. Often, the technical expertise of local building officials needs improvement. Given Mexico’s mandate for sustainability, it will become crucial to disseminate the importance of specific building techniques in the future.

Land Use
Ejido land comes with a particular set of requirements, as much of it is controlled by a small group of decision makers. The general subdivision of it is largely predetermined, but parcels can be turned over for development if the community desires to make land transfers. In the rural and industrial outskirts, land use is more restrictive than in the compressed urban condition, but this does not seem to affect the maximization of the use and enclosure of parceled land by occupants. The idea of "internalizing" the use of the land for privacy is a distinct Mexican theme. The actual house may be smaller than this boundary or enclosure, but the typical planning ideal does not always focus attention towards the street.

Visual Aspects
Exposed masonry and raw concrete are stereotypical in Mexico, and unfinished elements such as castillos protruding from tops of walls are quite common. At times this exposure is a disadvantage, as grouting is not always professional, and the sometimes piecemeal nature of the material assemblies can lead to a mismatched and patchy visual presentation. The unfinished visuals can sometimes be perceived as “failure” to complete the project. Another typical condition is a flat concrete roof - which can symbolize a potential for vertical expansion. However, many families would prefer a sloped roof, which they find to be a status symbol. Stepped facades and small cantilevers are not uncommon, to increase areas on upper levels. Paint and smooth troweled concrete or plaster are most often used as exterior finishing products.

Public Policies
The Mexican government has implemented a National Infrastructure Program, which will affect not only its transportation sector, but also its communications networks, along with its energy sector. An ambitious 2030 Water Agenda has been implemented which will address sanitation, supply, and redistribution of the resource to the community. After COP21 in Paris, Mexico introduced a major new policy on clean energy — its Energy Transition Law, which includes a clean energy targets for electricity by 2024. Mexico is becoming a world leader in sustainable building, and its policies are being guided in this direction.

Production Processes
Prefabrication is not uncommon, and given the proliferation of gray masonry units, it would appear to be economical and somewhat advantageous to the self-builder. The most professional results are obtained when these components are utilized by a skilled consumer. Handmade brick is not uncommon, but its implementation is not always precise. A greater level of precision seems to be achieved with larger construction components. Concrete for foundations / floors / roofs / columns is often mixed outside without power tools, and hard, physical labor is the method of choice on most sites. Only the simplest of tools are typically used, including water levels created from tubing.

Mexico Housing 5
Mexico Housing 6

Footnotes:


  1. Disenio and Viviendia Public en Mexico, Universidad Autonoma Metropolitana, 1991 - pg 25
  2. https://en.wikipedia.org/wiki/Querétaro_City
  3. http://www.worldbank.org/en/results/2013/04/17/mexico-seeks-to-adapt-to-climate-change-and-mitigate-its-effects
  4. Walker, Alex, Historical Influences on the Use of Cement in Mexican Domestic Construction, 2000, pg 95-96
  5. http://www.ibtimes.com/mexicos-economy-rising-poverty-inequality-undermine-pena-nietos-economic-agenda-2080010
  6. Fry, Matthew Joseph, Mexico’s Concrete Block Landscape: A Modern Legacy in the Vernacular, 2008, pg 23
  7. Ibid, PG 43
  8. Ibid, pg 45
  9. Ibid, Abstract
  10. http://www.goodnewsnetwork.org/poor-family-mexico-given-new-home-new-start/
  11. https://www.mexperience.com/bottled-water-in-mexico/
  12. Indigenous Peoples’ Right To Adequate Housing A Global Overview (UN-HABITAT 2005), pg 140
  13. The term informal is associated with the work of the economist Hernan de Soto in Peru and his ideas about how to harness the informal economies of Lima to a productive system, the state economy
  14. Pierce, Emmet, Harvard Survey Highlights The Differences In U.S. And Mexican Housing Markets, San Diego Union Tribune, August 8, 2004
  15. Haven, Gilbert, A Winter In Mexico, 1875, Harper & Brothers, New York, pg 284
  16. Krohn, Haakon S., Downtown Santiago de Querétaro, 2009
  17. http://thesis.edburg.com/node/178
  18. http://climateactiontracker.org/countries/mexico.html
  19. https://en.wikipedia.org/wiki/Querétaro (Geography and Climate)
  20. Board of Regents, The University of Texas System, based on the kÖppen classification of climates
  21. https://en.wikipedia.org/wiki/Water_supply_and_sanitation_in_Mexico


References:


  1. Edburg, Alan & García, Israel, Quality In Social Housing For Querétaro, Mexico, ETH Zuerich · Department Architektur, 2006/2007
  2. Current Housing Situation In Mexico, 2011 (CIDOC and SHF)
  3. Herbert, Christopher E. , Belsky, Eric S., and DuBroff, Nicholas, The State of Mexico’s Housing – Recent Progress and Continued Challenges, Joint Center for Housing Studies, Harvard University 2012

Mexico: Self-Built Housing in Querétaro (2017)

Project Architect: Russell Thomsen (RNThomsen Architecture)

Research / Collaboration: AJ Rosales

PROMPT: In the last century, Mexico's housing planning and development has seen many difficulties. From overcrowding to unsafe edifices, there are many issues that need to be addressed as the country moves forward. I participated in the INFONAVIT Manos a la Obra competition with Russell Thomsen, a SCI-Arc professor. This article catalogs several weeks of research and diagramming that I contributed to the eventual design project / competition entry, which synthesized the information presented here.