AU2004100880A4

AU2004100880A4 - Membranous Termite Barrier

Info

Publication number: AU2004100880A4
Application number: AU2004100880A
Authority: AU
Inventors: Terry Trapnell
Original assignee: WHITE ANT Co Pty Ltd
Current assignee: WHITE ANT Co Pty Ltd
Priority date: 1998-12-21
Filing date: 2004-10-15
Publication date: 2004-11-11
Anticipated expiration: 2007-12-08

Description

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AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR AN INNOVATION PATENT The White Ant Company Pty Ltd Mr Terry Trapnell CULLEN CO.

Patent Trade Mark Attorneys, 239 George Street Brisbane QId 4000 Australian Membranous Termite Barrier Name of Applicant: Actual Inventor: Address for Service: Invention Title: Details of Associated Divisional Application Australian Patent Application No.

2003100834 filed 3 October 2003 The following statement is a full description of this invention, including the best method of performing it, known to us: 2 c MEMBRANOUS TERMITE BARRIER SThis invention relates to the protection of buildings from O subterranean termites and is particularly concerned with membranous termite barriers for incorporating into concrete slab-on-ground buildings having a masonry veneer cladding, during their construction.

0Subterranean termites typically build nests just beneath the soil 00 0- surface and forage, principally for cellulose containing material, for distances _which can reach hundreds of metres from their nests. Termite damage to buildings, particularly residential buildings can be as many as one building in cfive in some parts of Australia, costing the community many tens of millions of dollars annually in the repair of the affected timber. As a result, the Australian Building Code has made it compulsory for all new buildings to incorporate suitable termite barriers. The currently Building Code is laid down in Australian Standard 33460.1-1995. This standard specifies three permissible systems for protecting concrete slabs from termite penetration. The systems comprise the use of stainless steel mesh, graded stone or chemicals.

Chemicals soil barriers have recently come under attached by environmentalists on the basis that their toxicities may be harmful to man.

This has lead to the banning of conventional chemicals and the use of more environmentally friendly materials. Unfortunately such materials are less effective and have no effect whatsoever after as little as twelve months from application.

Graded stone barriers must satisfy a large number of criteria to be effective. The stones must be of crushed igneous or metamorphic origin, be from a sound source, have a minimum sg of 2.52, and be graded and shaped so that the termites cannot lift them or penetrate their voids. A typical product meeting these requirements is GRANITGARD®, which is granite stone, supplied by CSR Readymix, a Division of CSR limited. The problem with such products, however, is that they cannot effectively be used on sloping ground surfaces, supply in many parts of Australia is difficult, and they are relatively expensive.

Stainless steel mesh barriers are consequently now in widespread use. These barriers are, nevertheless, not without their 3 0 0 drawbacks. Apart from their relatively high cost, which cannot be avoided, t there are particular problems when it comes to their installation at the O perimeter of concrete slabs having masonry veneer walls. The commonly used method comprises parging an inner edge of the mesh to be perimeter of the slab and extending the mesh out under the row of bricks which I 0 substantially level with the slab. The parging material is an adhesive, which is 00 0 required to be termite resistant, form a strong bond between the mesh and _the concrete, and be durable over the life expectancy of the building. In practice, however, it is difficult to form a proper seal with the parging material due to the relative movement between the bricks and the concrete slab due to different rates of drying, and expansion and contraction taking place. the integrity of the seal is therefore frequently broken and regions for termite entry are provided.

DESCRIPTION OF THE PRIOR ART One way of overcoming the previous problems is the subject of Australian Patent Application No. 64411/96. This patent application describes a physical termite barrier for incorporating in the perimeter of a concrete slab and an adjacent masonry wall. It comprises a continuous sheet 2 0 of termite resistant material, selected from sheet metals and sheet plastics materials, which has a substantially Z-shaped profile incorporating movement resisting deformations. Curved regions are provided where the three planes of the sheet meet which function to assist the barrier to resist sheer fracture when the barrier is set in the concrete slab and the barrier is set in the concrete slab and masonry wall. The barrier is arranged in situ with one end planar section extending substantially horizontally into the concrete slab, inwardly of the perimeter, the other planar end section extending in the masonry mortar over the upper surface of the upper row of perimeter bricks/blocks, and the intermediate planar section extending perpendicularly within the slab adjacent the perimeter thereof.

While such a barrier is an extremely effective termite barrier for the life of the building, it has the disadvantage that if the adjacent masonry slab if not built to the correct tolerances, then the barrier will not be positioned in the most effective location within the mortar joint. Furthermore, the relative 1- 4

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0inflexibility of the barrier can give rise to other minor difficulties in the handling t and laying of the product.

O OBJECT OF THE INVENTION It is therefore an object of the invention to provide a termite barrier which has all of the advantages of the termite barrier of Australian 0 Patent No. 64411/96 but which does not have the disadvantages referred to 00

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0 above.

_SUMMARY OF THE INVENTION 10 According to one aspect of the present invention there is provided a membranous termite barrier which is adapted to extend between the mortar course of a masonry wall and an adjacent concrete slab, said membranous termite barrier comprising a matting impregnated with a termite resisting product, said matting being sufficiently absorbent to facilitate its impregnation with the liquid termite resistant product.

The matting is typically in the form of a longitudinally extending strip which can be rolled out over an upper coarse of the masonry wall (which at this stage of construction is only a few courses high) and can be adhered 2 o to the adjacent concrete slab.

The edge of the matting strip which is adapted for location on the upper coarse of the masonry wall, within the mortar joint, preferably has an associated inspection band welded or adhered along its edge in order to enable the mortar joint to be racked without destroying the edge of the matting, and to ensure that the termite resistant product embedded therein is not lost by evaporation to the air or diluted by moisture absorption from the air.

According to a second aspect of the invention, there is provided a method for installing a membranous termite barrier of the aforementioned type, in situ which method comprises the steps of: adhering an inspection band to the horizontal outer edge of a masonry course which lies adjacent a concrete slab, (ii) laying a continuous bead of termite resistant adhesive along the upper surface of the inspection band and also along a face of the 0 0 concrete slab to which the membranous termite matting is to be joined, t (iii) placing the membranous termite matting between the O beads of adhesive so as to extend lengthwise between the upper surface of the masonry course and the concrete slab, and (iv) coating and/or impregnating the membranous termite 0 omatting with a termite resistant product.

0DETAILED DESCRIPTION OF THE INVENTION 0The membranous termite matting can be fabricated form natural or artificial fibres, or mixtures thereof, which can be formed in small discrete 0lengths or long fibers which are woven into fabrics. Particularly suitable mattings include fiberglass matting, polyester and polyethylene waddings and fabrics such as geofabrics, and combinations of these materials.

The termite resistant product is not a "termiticide" of the type which has been used in the past which was toxic to humans, but a product which is environmentally friendly but nevertheless toxic to termites. A range of such products are now commonly available and these include the pyrethrums, chlorpyrifos and chlorfos.

Suitably, the termite resistant product incorporates a waterproofing compound, or mixture of such compound and/or other active ingredients, additives or diluents. Typical examples of such additives include petroleum by-products such as creosote, and polyurethane base water repelling agents such as orminoid®.

The inspection band is a non-absorbent sheet of plastics material or other such material which can be joined to the membranous termite barrier either during or prior to construction. Preferably it is joined after construction, that is, it is a separate item which is independently fitted to the masonry layer before the membranous termite barrier is laid in situ. The inspection band can be polyethylene or like band which is fitted so as to have an edge which is flush with the face of the masonry so as to form a visible inspection strip to detect any termite intrusion.

The membranous termite barrier is easy to install because of its flexible characteristics, and can be sold in convenient coiled rolls.

Impregnation with the termite resistant product can be made either prior to 1- 6

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0 sale or, preferably, at the site of installation.

t BRIEF DESCRIPTION OF THE DRAWINGS 0 Figure 1 is a cross-sectional view of a membranous termite barrier fitted between a brick course and a raft slab, Figure 2 is a cross-sectional view of a membranous termite 0 barrier fitted between a brick course and an infill slab according to one 00 o method, and 0Figure 3 is a cross-sectional view of a membranous termite barrier fitted between a brick course and an infill slab according to another 0method.

DESCRIPTION OF PREFERRED EMBODIMENTS Preferred embodiments of the invention will now be described with reference to the accompanying drawings in all of which like reference numerals refer to like parts.

Referring firstly to Figure 1, there is depicted a brick course a concrete raft stab 11, a foundation 12 and a base plate 13 of a building.

A thin band 14 of a polyethylene plastics material is fixed with a termite resistant adhesive to the upper outer edge of the brick course 10 so as to be flush with the outer edge thereof. The band extends about two fifths of the way across the brick course and extends lengthwise along the brick course. The adhesive used to fix the band forms a continuous unbroken termite barrier.

The membranous termite barrier 20 comprises a strip of polyester woven fabric which is adhered to the band 14 of plastics material at and to the outer face of the concrete slab 11 as The adhesive is such as to form a continuous seal along the outer face of the slab. An adhesive bead seal 17 is also formed on the outer facing edge of the membranous termite barrier The membranous termite barrier 20 extends the entire length of the brick course 10 and forms a continuous curved portion 15 across the cavity 16. It is impregnated with a termite resistant product including a waterproofing agent, which consists of a mixture of 5% by weight creosote, by weight cholorpyrifos and 90% by weight orminoid®.

7 0 0 The Figure 2 embodiment to which reference is now made, t differs from Figure 1 in that there is no cavity and the membranous termite O barrier 21 is laid flat across the top of a horizontal portion of a rebate 18 in the concrete slab 11. Adhesive 19 is applied to the horizontal portion of the rebate and a bead of the adhesive is also applied to the upper corner region 0 as illustrated. The rest of the termite barrier is as described above with 00 o respect to Figure 1.

0Figure 3 illustrates the same masonry/slab construction as Figure 2 but here the membranous termite barrier 22 is curved upwardly at 24 0and adhered at to the vertical face 23 of the rebate 18. An adhesive bead seal 25 is also formed on the top upper facing edge of the membranous termite barrier 22 to prevent moisture being absorbed into, or termite resisting product being released from, the edge of the barrier.

Whilst the above has been given by way of illustrative example of the invention, many modifications and variation may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

Claims

2. A membranous termite barrier as claimed in claim 1, wherein the matting is fiberglass, polyester or polyethylene wadding, or geofabric. 0
3. A membranous termite barrier as claimed in any one of the preceding claims, wherein the termite resisting product additionally includes a waterproofing compound.
4. A membranous termite barrier as claimed in any one of the preceeding claims wherein the barrier comprise a mat pre-impregnated with termite resisting compound.
5. A membranous termite barrier as claimed in any one of the preceeding claims wherein the barrier is formed by applying a termite resisting compound to a substrate and applying the mat to the termite resisting compound and optionally covering the mat with additional termite resisting compound. Dated this 15 th Day of October 2004 The White Ant Company Pty Ltd By its Patent Attorneys CULLEN CO.