Scoring Guide
How CarCareTruth Scores Glazes
Last updated 2026-05-08
What We Measure — and Why It Matters
A glaze does one thing that no wax or sealant can: it fills light defects — swirl marks, fine scratches, haze — with oils and silicones so they become nearly invisible. It is not a correction tool (no abrasive) and it is not a standalone protectant (you still need a wax or sealant on top). The central question in glaze is whether it actually hides defects, and for how long. CarCareTruth measures community-confirmed defect-filling effectiveness, not manufacturer fill-and-shine copy.
The Quality Score
Quality is 60% of the Stage 1 formula. The dominant dimension is defect-filling ability — how visibly it masks swirls and fine scratches under real-world light, confirmed by before/after community photos and forum application reports. A glaze that makes a swirl-covered dark car look freshly detailed scores near the top; one that adds gloss without filling scores close to a plain spray wax.
The second dimension is gloss and wet-look depth: does it produce the deep, oily "wet car" look buyers specifically choose a glaze to achieve? Third and fourth at equal weight are fill durability — how many wash cycles the masking effect holds — and application ease and LSP compatibility — whether it buffs off cleanly and plays well with the wax or sealant applied over it. A glaze that causes the topcoat to fish-eye or peel is a compatibility failure, not just an inconvenience.
The Health Score
Glazes range from nearly benign to moderately hazardous depending on carrier chemistry. Water-based silicone emulsions (60%+ water, dimethicone base) score in the 7.5–9.0 range — the oil and silicone carry minimal health risk. Traditional petroleum-oil or naphtha-carrier show glazes score in the 5.5–7.0 range — they may carry a DANGER signal word from a skin sensitizer classification, elevated VOC, or Proposition 65 disclosures, depending on the specific petroleum fraction. These are real chemistry-based classifications, not generic SDS disclaimer language. The health score reflects actual chemistry, not generic SDS disclaimers. Buyers who want to minimize chemical exposure can choose a water-based formula and score meaningfully better on health — unlike categories where all products are similarly hazardous.
The Environment Score
Glaze is a leave-on product — it stays on the car's paint surface and weathers off gradually rather than going down a storm drain. Environment deductions from petroleum-carrier VOC are reduced by a ×0.75 multiplier compared to rinse-off products. Even so, traditional naphtha-carrier glazes (50%+ petroleum fraction) carry enough estimated VOC to score in the Notable Concerns range (3–5). Water-based glazes with no volatile co-solvent reach the Environmentally Responsible range (7–8). Most products score between 5 and 8. No mainstream glaze contains PFAS.
The CCT Score
Quality 60%, Health 25%, Environment 15% (Stage 1) — then blended at 75% with a 25% CCT Opinion editorial score (Stage 2). Quality carries the most weight because defect-filling is what distinguishes a good glaze from a mediocre one, and health varies enough across the category (3.5-point typical range) to be a real differentiator. A glaze with a quality score of 7.0, health score of 8.0, and environment score of 6 produces: Stage 1 = (7.0 × 0.60) + (8.0 × 0.25) + (6 × 0.15) = 4.20 + 2.00 + 0.90 = 7.10. With a CCT Opinion of 7.0 (null substitution): Stage 2 = 7.10 × 0.75 + 7.0 × 0.25 = 5.325 + 1.75 = 7.075 — just above the Recommended threshold.
What This Score Doesn't Measure
Scores are based on SDS analysis, ingredient chemistry, and community/Amazon data — not hands-on product testing. Glaze performance is paint-condition-dependent: a glaze works best on paint that has been clayed and is free of heavy scratches. On deeply scratched paint, even the best glaze scores no better than 6 on defect-filling because no amount of oil and silicone fills a visible scratch — paint correction is the correct tool there. The fill-durability score reflects typical outcomes on maintained paint washed weekly; high-pressure washing, harsh soaps, or neglected paint will reduce fill durability below the score anchor. The CCT Score also does not measure whether a glaze is compatible with every specific topcoat product — the application_ease dimension captures documented incompatibility reports, but novel combinations may not be in community data yet.