Project Guide
Project Level: easy
Project Length: 15 Minutes
Why Do You Seal Cracks?
Cracks in concrete indicate an underlying problem that has caused the slab to shift. The most common issue is soil instability caused by moisture intrusion, improper site preparation or poor soil conditions. Most cracks are “active, meaning that patching with a cementitious product is a losing battle – the crack will appear again until the underlying issue is remedied.
Once a crack appears, the most important thing to do is seal it with a flexible material to prevent moisture intrusion which could further accelerate the instability causing the crack.
Project Prep
The most important consideration is that the crack is large –and clean –enough to accept the crack repair material chosen for the job.
- Estimate the amount of material required. One bottle of Sakrete Crack Filler will seal about 35 linear feet. All tube products will seal about 12 linear feet, depending on depth and width of the crack.
- Use the Crack Repair Calculator for fast results.
- Use a narrow chisel to widen the crack to a uniform width and form into a “V”-shaped channel. This is especially critical with narrow cracks.
- Clean out the crack with air or water to ensure all particulate is removed. Any dust or loose concrete can act as a bond breaker.
- Check the depth of the crack. If it exceeds 3/8” deep, back-fill with sand or closed-cell backer rod.
- Use the Slab Repair Calculator for precise estimates of the amount of product needed.
Project Tip: Use the Sakrete App to measure, estimate and purchase materials for the job straight from your phone.
