Side-by-side comparison
Valspar Prep Step Whole House Primer Flat Tintable White vs Sherwin-Williams CONFLEX Block Filler Flat White
| Fact | Prep Step Whole House Primer | CONFLEX Block Filler |
|---|---|---|
| Use | Exterior primer | Exterior primer, Interior primer |
| Sheen · base | Flat · Tintable White | Flat · White |
| VOC (untinted) | <50 g/L | 9 g/L |
| VOC added by tint | Not stated | Not stated |
| Emissions testing | Not documented | Tested (LEED emissions) |
| Health certification | None found | None found |
| Safety Data Sheet warnings | 3 | 3 |
| Ingredient disclosure | Safety Data Sheet only | Partial (environmental data sheet) |
| Safety Data Sheet revised | 8/18/2026 | 8/9/2026 |
Highlighted rows are where the two products differ. Facts come from each maker's documents; "not disclosed" means the maker hasn't published it, not that the product failed a test.
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Scores summarize the evidence makers publish. They don't guarantee safety or predict individual health outcomes. How we score
Sources
Valspar Prep Step Whole House Primer
Sherwin-Williams CONFLEX Block Filler