Circular marks on patio slabs - Incorrect installations??

[claire]

Hi

I had a patio layed just over a year ago (wet pressed concrete slabs) which immediately showed circular marks on a majority of the slabs. I spoke to the manufacturer who siad this was likely to be salt and would disappear in time but to call back if it didn't. I also stated slabs delivered were very different colour to those seen at the supplier.

As advised I left this for another 10 months and with no improvement to the marks I called back at which point photos were requested.

I have now received a letter stating that the installation method used is incorrect and is causing these marks. I paid for the patio to be installed professionally and believe from what I have read on this site a close joint method has been used. The manufacturer is stating that this method would cause the stains as water would collect causing a chemical reaction, leading to a darkening on the perimeter of the flag.

Sure markings were there before slabs were even laid... Also I brought some more slabs in store for umbrella stand and these seem a completely different colour.

Can you please advise is the installation method likely to have caused this? Is there anything I can do to improve appearence? would re-laying with bigger gap really resolve or could I use some kind of coloured sealant?

Sorry for long query, but so disappointed with results after spending my hard earned cash. Any advise appreciated?

[GB_Groundworks]

a photo would help a lot. you'll need to host it somewhere on the net to post it here or if you email it me i'll post it up here

giles@gbgroundworks.com

[seanandruby]

Is it just one large circular mark, or 5 small ones, one on each corner and one in the middle?

[claire]

Thanks, I have emailed some picture to be put on. Couldn't do this myself....

Usually larger mark in middle but on majority of slabs.

[GB_Groundworks]

full size one here

http://www.flickr.com/photos....ostream