b'TECH TALK tionsoftheself-leveler,adhesive4. Mix properly: Mix your self-and fl to determine if mois- levelingunderlaymentwithinooring ture mitigation is needed. the water range specifi ed on the If moisture mitigation is required,bag. Overwatering will lower the this must be done prior to installa- strength of the underlayment and tionoftheself-levelingunderlay- cancausecrackingandpinhol-ment. ing.Additionally,awhitefi lm Self-levelingunderlayments(effl orescence)mayformonthe (SLUs) require the use of a primersurfaceofthecuredunderlay-prior to installation. Primer retainsmentiftheproductisoverwa-the moisture within the self-level- tered. This fi lm can act as a bond ing underlayment to properly cure.breaker if the mortar bonds to the Secondarily,itactsasabondingsalts instead of the SLU. Do not agenttoensuretheSLUbondsovermixit,asthiscanmakeit properly to the substrate. Refer toharder to work with and lead to theprimerlabelforinformationcracking or improper fl ow. Mix a regarding application methods andmaximum of two bags at a time dilution per ASTM F3191. whenbarrelmixingtoensure Beyondpriming,mostself-lev- aproperblend.Followequip-elingunderlaymentsrequirethatment and product manufacturers the substrate be free from any con- recommendations when pumping taminantsthatmayinhibitbond,self-leveler.including oil, grease, dust, loose or peelingpaint,seal-ers,fl oorfi nishes, curingcompounds orcontaminants. Someunderlay-mentswillrequire acertainconcrete surfaceprofile (CSP),andinthese cases,mechanical abrasion,likeshot-blasting, is required. Make sure the sub-strateiscontami-nantfreeandhas thenecessarysur-faceprofi lebeforeTEC Level Set 200 was designed for the fast leveling of fl oors. It is both pourable and pumpable to fi t your job starting the pour.needs.76 TileLetter | October 2019'