Termite barrier

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Termite barriers are materials that have been specifically designed to prevent subterranean termites from gaining access to a structure. Physical termite barriers are free of pesticides and physically block termite foraging activity. Development of physical barriers to effectively exclude subterranean termites makes it possible to design and build structures with a far lower possibility of termite invasion and damage over the life of the building. Because of their small size (0.02 inches (0.51 mm) long), impressive reproductive capability (a termite queen produces one egg every 3 seconds, or over 10 million eggs per year), and ability to eat through many construction materials, termites are the most destructive of all insects.

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Termite shields, an early physical barrier, are sheet metal fabrications used for decades in light frame construction. Termite shields are often applied underneath wood sill plates. They are designed to force termites to build their mud tubes outside of the structure, where they become visible to a trained pest management professional. (See Termite shield)

Membranes

Termite membrane barriers consist of elastomeric sealants adhered to a high-strength backing. When included in the building envelope, membrane barriers perform multiple functions. In addition to excluding termites and insects, they act as waterproofing, air barrier, and vapor barrier.

A Formosan termite and waterproofing barrier installed on a foundation in Greenville, SC Foundation barrier Greenville SC.jpg
A Formosan termite and waterproofing barrier installed on a foundation in Greenville, SC

Applications for termite membranes include on concrete foundation walls, ICF insulated concrete forms, under-slab waterproofing, under-sill plates, flooring underlayments, and as wall, window, and door flashings, among others. Most termite membranes must be implemented during the construction process.

Sealants

Termite sealant materials are the basic component of termite membranes described above. Sealants are elastomeric, meaning they move with the structure without tearing, and are available in a caulk or spreadable formulation. When caulked around a plumbing penetration in a structure, termite sealant barriers adhere to both the pipe and the concrete. As the structure moves during settling or due to expansive soils, the sealant barrier material maintains a barrier impenetrable by termites and other insects.

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Stainless steel screens

To effectively exclude subterranean termites, screen apertures smaller than 0.02 inches (0.5 mm) are required. [1] Application areas for screens in the building envelope include weep holes, soffits, gable and ridge vents, among others.

Particle barriers

Particulate termite barriers are widely used around the Pacific Basin. Developed commercially by University of Hawaii scientist Minord Tamashiro in the 1980s. However, particle barriers only recently became commercially available in the mainland United States. The principle behind particle barriers has been well researched by Ebeling and Pence (1957), [2] Su et al. (1991), [3] Su and Scheffrahn (1992), [4] Yates et al. (2003), and Keefer et al. (2013). [5] Basaltic termite particle barriers are used in Hawaii, but hardly any place else, because basaltic rock comes from volcano activity, which only takes place in isolated areas of the world. Any hard mineral, such as granite which is used in Australia, will work as a termite barrier if it has the requisite size and shape properties.

Research with particle barriers began at Texas A&M University in 2003. Various particle characteristics were evaluated, including size, angularity, and interstitial space between particles. [5] This material can be installed around the exposed perimeter of a home or structure in a wedge formation that measures 4 inches (100 mm) across and 5 inches (130 mm) down, directly against the foundation.

Stone particle barrier at exposed concrete foundation Photo particle barrier.jpg
Stone particle barrier at exposed concrete foundation

Aggregate barriers have also shown success when installed in bath traps or slab leave-outs. During construction and after the foundation is poured, cardboard and other debris is removed from bath trap areas and the particle barrier is installed. Application of this material protects the structure from termite intrusion in a vulnerable entry point.

One problem with particle barriers is that there are erroneous references on the Web to the use of particle barriers to stop termites. One source says "use a sand barrier". Another says that "16 grit sand is acceptable". Although this loose specification is appreciated by some building contractors who can purchase "sand" or "16 grit sand" inexpensively at lumberyards and other outlets, it has the effect of damaging the credibility of particle barriers as a termite protection method. All of the research listed above, which took place at universities of California-Berkeley (1956), Hawaii (1982 - 2003), Florida (1992), and Texas A&M (2003 - 2013)pointed to sizes between 8 and 14 as being most effective.

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Termites are a group of detritophagous eusocial insects which consume a wide variety of decaying plant material, generally in the form of wood, leaf litter, and soil humus. They are distinguished by their moniliform antennae and the soft-bodied and often unpigmented worker caste for which they have been commonly termed "white ants"; however, they are not ants, to which they are distantly related. About 2,972 extant species are currently described, 2,105 of which are members of the family Termitidae.

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<span class="mw-page-title-main">Formosan subterranean termite</span> Species of termite

The Formosan termite is a species of termite local to southern China and introduced to Taiwan, Japan, South Africa, Sri Lanka, Hawaii, and the continental United States.

<span class="mw-page-title-main">Vapor barrier</span> Damp proofing material in sheet form

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<i>Reticulitermes flavipes</i> Species of insect found in North America

Reticulitermes flavipes, the eastern subterranean termite, is the most common termite found in North America. These termites are the most economically important wood destroying insects in the United States and are classified as pests. They feed on cellulose material such as the structural wood in buildings, wooden fixtures, paper, books, and cotton. A mature colony can range from 20,000 workers to as high as 5 million workers and the primary queen of the colony lays 5,000 to 10,000 eggs per year to add to this total.

<i>Trichonympha</i> Genus of flagellated protists

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<span class="mw-page-title-main">Rainscreen</span>

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<span class="mw-page-title-main">Termite shield</span>

A termite shield is a sheet metal fabrication used in light frame construction to reduce the movement of termites from the soil into wood framing members such as floor joists and studs. Although there are several types of non chemical termite barriers now in use, termite shields are the original.

<i>Reticulitermes</i> Genus of termites

Reticulitermes is a termite genus in the family Rhinotermitidae. They are found in most temperate regions on Earth including much of Asia and the Middle East, Western Europe, and all of North America.

<i>Incisitermes minor</i> Species of termite

Incisitermes minor is a species of termite in the family Kalotermitidae known commonly as the western drywood termite. It is native to western North America, including the western United States and northern Mexico. It has been found in many other parts of the United States, all the way to the East Coast. It has been reported from Toronto. It has been introduced to Hawaii. It has been noted in China and it is not uncommon in Japan. This is an economically important pest of wooden structures, including houses. In California and Arizona alone its economic impact is estimated to be about $250 million per year.

<i>Coptotermes</i> Genus of termites

Coptotermes is a genus of termites in the family Rhinotermitidae. Many of the roughly 71 species are economically destructive pests. The genus is thought to have originated in Southeast Asia. Worker termites from this genus forage underground and move about in roofed tunnels that they build along the surface.

<i>Coptotermes acinaciformis</i> Species of termite

Coptotermes acinaciformis is a species of subterranean termite in the family Rhinotermitidae native to Australia. Termites are social insects and build a communal nest. In the case of C. acinaciformis, this is either in the root crown of a tree or underground. From this, a network of galleries extends through the nearby soil, enabling the workers to forage in the surrounding area without emerging on the surface of the ground. This termite can cause substantial damage to trees and the wooden parts of buildings.

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Nasutitermes ceylonicus, is a species of termite of the genus Nasutitermes. It is found in Sri Lanka. It is a pest of tea and coconut. It damages numerous wooden constructions, and timber in buildings.

Amitermes floridensis, commonly known as the Florida darkwinged subterranean termite, is a species of eusocial insect in the family Termitidae. It feeds on rotting wood, reached by a network of tunnels. It is endemic to west central Florida and was first described in 1989.

<i>Reticulitermes tibialis</i> Species of termite

Reticulitermes tibialis, the arid-land subterranean termite, is a species of termite in the family Rhinotermitidae. It is found in the United States, mostly in the western half, occurring in deserts, prairies and other dry locations.

Holomastigotoides is a genus of parabasalids found in the hindgut of lower termites. It is characterized by its dense, organized arrangement of flagella on the cell surface and the presence of a mitotic spindle outside its nucleus during the majority of its cell cycle. As a symbiont of termites, Holomastigotoides is able to ingest wood and aid its host in digestion. In return, Holomastigotoides is supplied with a stable habitat and steady supply of food. Holomastigotoides has notably been studied to observe the mechanisms of chromosomal pairing and segregation in haploid and diploid cells.

References

  1. Geiger, Chris A.; Cox, Caroline. "Pest Prevention by Design" (PDF). San Francisco Environment. Retrieved 23 February 2017.
  2. Ebeling, Walter; Pence, Roy J. (May 1957). "Relation of Particle Size to the Penetration of Subterranean Termites through Barriers of Sand or Cinders". Journal of Economic Entomology. 50 (5): 690. doi:10.1093/jee/50.5.690.
  3. Su, Nan-Yao; Scheffrahn, Rudolf H.; Ban, Paul M. (1991). "Uniform Size Particle Barrier: A physical exclusion device against subterranean termites (Isoptera: Rhinotermitidae)". Journal of Economic Entomology. 84 (3): 912. doi:10.1093/jee/84.3.912.
  4. Su, Nan-Yao; Scheffrahn, Rudolf H. (1992). "Penetration of sized-particle barriers by field populations of subterranean termites (Isoptera: Rhinotermitidae)". Journal of Economic Entomology. 85 (6): 2275. doi:10.1093/jee/85.6.2275 . Retrieved 24 February 2017.
  5. 1 2 Keefer, T. Chris; Zollinger, Dan G.; Gold, Roger E. (September 2013). "Evaluation of aggregate particles as a physical barrier to prevent subterranean termite incursion into structures" (PDF). Southwestern Entomologist. 38 (3): 447–464. doi:10.3958/059.038.0308. S2CID   85870420 . Retrieved 23 February 2017.
  1. Scientific American; https://blogs.scientificamerican.com/running-ponies/long-live-the-morbidly-obese-termite-queen-and-her-terrifying-army-of-sweat-licking-babies/
  2. Pest Control Technology; https://www.pctonline.com/article/pct0215-annual-termite-damage-quest/
  3. Gold, Roger; (October 2015. "Pest Exclusion Using Physical Barriers - Part of the Sustainable Future for New and Existing Structures" (https://www.youtube.com/watch?v=2c2BEFq9Bmk. ' 'Pest World 2015 - National Pest Management Association' '). Retrieved 25 October 2017.
  4. International Code Council AC 380 "Acceptance Criteria for Termite Physical Barrier Systems" (http://shop.iccsafe.org/ac380-termite-physical-barriers-approved-oct-2014-editorially-revised-feb-2017-pdf-download.html)
  5. International Code Council ICC Evaluation Report ESR-3632 TERM Barrier System (http://www.icc-es.org/Reports/pdf_files/load_file.cfm?file_type=pdf&file_name=ESR-3632.pdf)
  6. International Code Council ICC Evaluation Report ESR-1860 Termimesh Termite Control System (http://www.icc-es.org/Reports/pdf_files/load_file.cfm?file_type=pdf&file_name=ESR-1860.pdf)