r/pavers

We recently had a pool deck replaced with paving stones. There are 2 areas on our deck where groups of pavers have a chalky white look when compared to the others. Also some of the pavers within a group look acceptable. I tried to capture this appearance in the photo and had to enhance the contrast and color to show the white haze. We've had the pavers pressure washed and then pressured washed with a special brush tool but that did not change anything.

Most of the searches suggest that it is efflorescence and that an efflorescence cleaner should be used. My initial thoughts was that some pallets of the pavers were different than others which would account for why this occurred in groups. We've been going back and forth with the contractor and they are reluctant to replace them for obvious reasons. Is this a common situation where only groups of pavers experience efflorescence? Could some of the pavers have been cured or manufactured incorrectly? Are there any other root causes and solutions that we should be exploring?

I don't think this is important but the details of the pavers are:

Manufacturer: Angelus Paving Stones

Design: Paseo I and II

Color: Adobe-Copper-Mocha

Thank you for your input.