METHOD STATEMENT 007 CEMENTITIOUS APPLIED MEMBRANE TO CONCRETE WALLS

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1 This Document is designed to cover best practice installation procedures for a cementitious liquid applied membrane system to concrete 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. ACCEPTANCE 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 TEMPERATURES Do not install any liquid applied membranes to substrates where the surface temperature is increasing or between 10 c or above 35 c. All Envirotech waterproofing solutions, systems installed in hot or cold substrates will obviously present problems due to accelerated and decelerated cure times. When and where possible, all membrane installations should be scheduled when temperatures are decreasing this can be early morning or late afternoons. SURFACE PREPARATIONS Surface preparation is the most critical aspect of installing a waterproofing membrane to basement areas, as we usually only have one chance. 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 set up.

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 waterproof membrane to complete the installation. PREPARATION METHODS Bevel by grinding all concrete edges by mechanical means to eliminate sharp edges Clean and prime High Pressure water-blasting 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 liquid applied membrane system to basement block walls I will propose that these best practice procedures be adopted into account as follows; The membrane systems should ONLY be a two-part cementitious membrane system such as Mapelastic Smart/Foundation. All membrane systems MUST be installed into a saw cut or reglet when terminating onto concrete footing, even if it cannot be installed on the down face of the footing. The membrane system where possible to be installed on the down face of the footing to stop slab edge dampness, and again into a saw cut or reglet. A suitable drainage system be installed below the top of the footing. The membrane system to be installed a minimum 150 mm above finished floor heights. 45 degree fillets to all junctions must be a minimum of 50 mm. Expansion joints to be sealed with an MS sealant, then bound with a continuous reinforced material such as Mapei-band.

4 BEST PRACTICE BASEMENT WATERPROOFING

5 COMMENT; IF MEMBRANE CANNOT BE RETURNED DOWN FOOTING FACE, A 4 mm SAW CUT MUST BE INSTALLED TO TERMINATE MEMBRANE SYSTEM AS BELOW;

6 CONCRETE FOOTING METHOD STATEMENT Repair all areas such as divots, and form work cavities with Mapei Quick patch and smooth off. Repair all concrete structural areas with Mapei P4G 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: Mapei BI-Block or Eco-prim grip All Primers shall be left to cure AS PER RECOMMENDED DATA SHEETS.

7 DETAILING JUNCTIONS AND EXPANSION JOINTS Install a polyester mat over all coved junctions apply two coats for a DFT of 0.8 mm. Apply bond-breaker tape such as Crommelin tape or suitable rubber bandage over all expansion joints in two coats for a DFT of 0.8 mm. Allow membrane to cure as recommended. MEMBRANE INSTALLATION Apply one coat of the waterproof membrane to all footing areas FIRST 50 mm away from the saw cut or reglet and to face wall rolling in a cross pattern. Apply the first coat of waterproof membrane to wall areas in a cross pattern. Allow membrane to cure as recommended. Apply a two more coats of waterproof membrane rolling in a cross section making sure to terminate the last coat of membrane into saw cut or reglet. DFT shall be 2.0 mm, or a third coat shall be applied after the recommended cure time. COMMENTS; MS SEALANTS CAN ONLY BE USED WITH WATER-BASED MEMBRANE SYSTEMS, NOT CEMENT BASED SYSTEMS, BUT IN THIS CASE WE ARE PROTECTED WITH THE MAPEI BAND.

8 COMMENTS; We would recommend that the waterproofing contractor protect the membrane system as specified below, rather than the builder. This shall eliminate any issues with the builder damaging, penetrating or cutting through the completed membrane system. PROTECTION You have gone to all that trouble waterproofing the retaining wall, so why install 2 mm 300 gsm Core-flute. Install 4.00 mm 600 gsm core-flute or pro-drainage boards SUITABLE MEMBRANES FOR BASEMENT WALLS Mapelastic Foundation Mapelastic Smart Gripset C1P COMPLETION Take a dated picture by camera, and store in folder. Clean up all empty buckets and materials and remove. Leave all work in a sound a condition and defect free.

9 Reference Contacts and Data: Technical data, advise or technical assistance may be obtained by contacting Enviro-Tech Waterproofing Solutions at:- Web Page Office Telephone: (07) Office Fax: (07) John Blasé Mobile: Postal address: Unit 254 Robinson Road East Geebung Qld 4034 Australia Do it Once-Do it Right-Fixed for Good