SEALANTS: THE LOWEST COST, HIGHEST RISK PRODUCTS IN GLAZING CARL TOMPKINS NATIONAL FLAT GLASS SALES MANAGER, SIKA CORPORATION

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1 SEALANTS: THE LOWEST COST, HIGHEST RISK PRODUCTS IN GLAZING CARL TOMPKINS NATIONAL FLAT GLASS SALES MANAGER, SIKA CORPORATION

2 INTERESTING AND TRUE Dollars and Sense Sealants represent $395 million dollars in annual residential and commercial glazing business. This equates to nearly 4% of total glazing revenue. Risk Most common reason for rework is resealing window and door systems. Cost is ten times larger than the resale price of weatherizing. 2

3 IT ALL BEGAN IN THE EARLY 17 TH CENTURY! The world of sealants began by combining linseed oil with chalk to create the first window glazing putty.! This glazing system worked well with the early mullioned timber windows utilized within iron casement systems.! The same concept of oil and resin based caulks led the way clear through the 1950 s.! Good system for weather sealing but no elasticity to allow for joint movement 3

4 OUR CURRENT SEALANT POSITION! The early 1960 s the introduction of the first truly elastic sealant polysulfide.! Later in the 1960 s the introduction of silicones that provided improved elasticity and temperature range for usage. 4! The 1970 s the introduction of polyurethanes, providing similar joint movement capabilities along with improved abrasion resistance and a paintable surface.! Today, silicones and polyurethanes are the two leading categories of commercial glazing sealant types.

5 ELIMINATING THE RISK: PART ONE USE THE RIGHT PRODUCT Flexible picture height ACRYLICS PAINTABLE LOW COST MOSTLY USED INDOORS POOR WEATHER RESISTANCE SHRINKAGE POOR DYNAMIC MOVEMENT CAPABILITIES 5 POLYSULFIDES PAINTABLE ADHESION CHEMICAL RESISTANT FAST CURE WEATERABILITY LOW TEAR STRENGTH MAY REQUIRE PRIMER LIMITED SERVICE TEMPERATURE RANGE POLYURETHANES PAINTABLE EXCELLENT ADHESION WEATHERABILITY CHEMICAL RESISTANT MECHANICAL PROPERTIES MAY REQUIRE PRIMER LOWER UV RESISTANCE SLOWER CURE OF 1-C SILICONES EXCELLENT UV STABLILITY ADHESION MOLD RESISTANT TEMPERATURE RESISTANCE EASY TO REPAIR NOT PAINTABLE POOR TEAR RESISTANCE FAST SKINNING BUT SLOW CURE COMPATIBILITY ISSUES WITH OTHER PAINTS AND SEALANTS

6 ELIMINATING THE RISK PART 2: JOINT PREPARATION 6 THE #1 REASON FOR SEALANT FAILURE: LOSS OF SUBSTRATE ADHESION 1. Remove loose debris from surface. 2. Use an approved solvent to remove contaminants, using a lint free type of cloth. 3. Immediately wipe cleaned area with dry, lint free cloth. 4. Joint must be dry and solvent free prior to sealant application. No frost or moisture allowed. KNOW YOUR SUBSTRATES. Some substrates may require a special cleaner or primer. Follow your sealant manufacturer s instructions.

7 ELIMINATING THE RISK PART 3: JOINT CONFIGURATION AND SEALANT APPLICATION 1. Use closed cell backer rod that is 25% larger than joint width to control depth and of seal and prevent 3-sided adhesion. 2. Tape all joints to contain joint overfills of sealant, provide professional appearance and edge protection. 3. Apply sealant into joint at a 30 angle, pushing the sealant into the joint with the caulk gun. 4. Tool the filled joint, leaving a concave surface, eliminating and voids and providing an hour-glass appearance to compensate for expansion and contraction of sealant during thermal change. 5. Note that all butt joint configurations should maintain a sealant depth of between ¼ and ½. 6. After tooling, remove tape and conduct general clean up, making sure that any cleaning solvents do not come into contact with the uncured sealant bead 7

8 ELIMINATING THE RISK OUR CONCLUDING RECOMMENDATIONS! Seek training and certification from your sealant manufacturer.! Conduct pull tail testing in all commercial field applications prior to weather sealing the project.! Pay attention to weather conditions All sealants cure rates and applications properties are affected by temperature and humidity ratings.! Follow the written word remain current on all PDS & MSDS documents, follow all pertinent instructions, document all extended warranties. 8

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