The best advice we can pass along for tooling sealants in saw cut and expansion joints in concrete slabs comes from Wayne BelCher from United Professional Caulking in Seattle. He is a recognized expert in the field and has published a reference book on waterproofing.
We recently watched him lead a team that was doing just this type of work. His advice was to use a combination of spatulas with both Passive and Aggressive tip shapes.
- (1) Passive Round Tip Spatula: 258 Classic Spatula or 958 Streamline Spatula
- (1) Aggressive Pointed Tip Spatula: 922-G01 CAT Spatula
- Caulk Gun. Suggested caulk gun B12S20
- Sealant of choice
FOLLOW THESE THREE EASY STEPS:
- DISPENSE sealant into the joints, overfill them slightly.
- PUSH forward with along the joint with a passive or traditionally shaped (rounded tip) spatula (258 Classic Spatula or 958 Streamline Spatula). Smooth and remove the excess caulk by scooping it off the substrate.
- PULL the sealant back towards you using an aggressive shaped (pointed tip) spatula (922-G01 CAT Spatula), Giving it the hourglass shaped profile that most sealant manufacturers recommend for the best elongation characteristics. Take note of the shallow angle of the spatula in this step.
FINSHED - Remember to clean off your spatulas for longer lasting tool!