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>Does anybody know how to stop this happening. I've heard there is a
barrier
>type spray I can use but does anyone know it's name ????
There are several different kinds of primer-sealers you can use. I would
suggest talking with your paint supply place and have them recommend
something. Since you have some bubbling, the chemicals may have seeped
further down and you may need to remove everything and start over. That
happened to me.