METHOD STATEMENT 006 TORCH APPLIED MEMBRANE TO BASEMENT WALLS

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1 This Document is designed to cover best practice installation procedures for a one layer torch applied sheet membrane system to basement walls. PRELIMINARY WORK Ensure that all surface preparation work, which shall include excess to perform the installation, all safety requirements are adhered too and the walls are complete and properly constructed to enable the membrane system to work as recommended and intended. Ensure that the blocks have been filled prior to installation and allowed to cure for 7 days, or has a moisture content of less than 75% RH before commencing any membrane application. ACCEPTANACE OF SUBSTRATE Confirm and assure that the substrate complies with relevant substrate standards for Waterproof membrane Systems, including any drainage requirements that may be needed. Insure that all safety procedures are matched and that any barricades or signage has been put in. SURFACE TEMPURATURES All torch applied sheet membrane systems shall be installed to a warm substrate, if cold weather is present, flame walls after priming to warm. SURFACE PREPARATIONS Surface preparation is the most vital aspect of installing a waterproofing membrane to basement areas, as we ordinarily just receive one opportunity. Ensure that the footing is clean from all dirt and other contaminants; and that the builder has excavated at least 200 mm below the top of the footing. Ensure with the builder if drainage is going to be installed.

2 When evaluating the substrate for preparation, certain aspects should be considered as follows: Condition and stability of the substrate. Moisture Tolerance. Degree of contamination. Curing compounds or release agents. Footing is acceptable for waterproofing. Face of footing is exposed for waterproofing. When the substrate has been inspected for the above criteria s, it is then possible to prescribe the correct preparation, a suitable primer and the sheet waterproof membrane. PREPARATION METHODS Bevel by grinding all concrete edges by mechanical means to eliminate sharp edges Clean and prime High Pressure water-blasting to clean Vacuuming

3 There are no waterproofing standards for basements/ below ground waterproofing, so we have to rely on best practice procedures or manufacturer's recommendations. In most cases the builder will require a form 16 and a manufacturer s warranty to be offered by the installer when completed. My opinion when installing a sheet membrane system to basement block walls I would advise these best practice procedures be adopted into account as follows; The membrane systems should be a TWO layer system. Not one layer. All sheet membrane systems MUST be terminated into a saw cut, reglet or by pressure seal. The sheet membrane system MUST BE installed on the down face of the footing to stop slab edge dampness, and again into a saw cut or reglet. All external corners should be beveled. A suitable drainage system IS ALWAYS PREFFRED BUT not critical with a sheet membrane system. Membrane system to be installed a minimum 150 mm above finished floor heights. 45 degree fillets to all junctions must be a minimum50 mm. Expansion joints internal/external junctions to be double detailed.

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5 BEST PRACTICE BASEMENT WATERPROOFING CONCRETE FOOTING Repair all areas such as divots, and form work cavity s with suitable concrete repair or similar and smooth off. Repair all concrete structural areas with epoxy gel, smooth off and sprinkle sand to finish. Allow curing for 24 hours. CONCRETE FILLETS Install concrete fillets 50 mm wide to cove with Mapegrout T40 or Mapegrout Fast-set and smooth off. EXPANSION JOINTS Joints to be cleaned out and filled with MS sealant and tooled off smooth. PRIMING APPLICATION Prime substrates thoroughly by brush or roller with the appropriate primer as follows: Bitumen primer, or recommended primer by manufacturer.

6 All Primers shall be left to cure AS PER RECOMMENDED DATA SHEETS. DETAILING EXTERNAL JUNCTIONS AND EXPANSION JOINTS Install a strip of membrane 200mm wide over joints and external corners MEMBRANE INSTALLATION Apply one layer of membrane to all footing areas FIRST 50mm away from the saw cut or reglet and install to one block high. Apply one layer of membrane to walls and terminate on the down face of the footing into saw cut or reglet. Pressure seal top edge of membrane to terminate. PROTECTION Protect membrane with a suitable protection such as Prodrain or a 3.0 mm 400 gsm protection board. In most cases we would recommend washed gravel be installed as backfill, or if soil is used it is best practice that soil be compacted.

7 COMPLETION Take a dated picture by camera, and store in a folder. Clean up all empty buckets and materials and remove. Leave all work in a sound a condition and defect free. Do it Once-Do it Right-Fixed for Good Reference Contacts and Data: Technical data, advise or technical assistance may be obtained by contacting Enviro-Tech Waterproofing Solutions at:- Web Page [email protected] Office Telephone: (07) Office Fax: (07) John Blasé Mobile: Postal address: Unit 254 Robinson Road East Geebung Qld 4034 Australia