Traidr977

any body had any probs w/ loxon for concrete block ext. i have a 4 year old job where the sheen is completely gone & chalked real bad. no adhesion prob. just failure to stand up to the elements.i used block filler, 1 coat loxon primer 2 coats loxon top coat.
they added a new section of building to do. any suggestions on a better system.also i charged time & material but am wondering what a typical sq ft price is for new block
thanks

NEPS.US

How long did the block sit before it was primed? Was the roof open for a long period of time? It sounds like alot of moisture is coming from the block. When was it done....weather situations. I've seen this in block done that has been done in the fall and sat over the winter and not had the proper time to dry in the spring before coating were applied. I've had great luck with loxon.

timhag

NEPS, if there was a moisture problem,,,,,would the paint bubble and peel? He doesn't mention any of that.

__________________
Doesnt hurt that you are a handsome and smooth Italian gentleman. Try selling with my looks and social graces. V DAWG

NEPS.US

There can be. But it can also bleed through the paint and appear to be chaulky and have no sheen.

Are you sure it was primed correctly with Loxon? Might not of even been primed.

vermontpainter

Based on his reference to the elements, I think he is talking exterior here.

__________________
Scott

"I feel stupid, and contagious..."

NEPS.US

Yes, but if the roof was open and if the elements got inside, then the roof and the building closed up ...the moisture is going straight to the block. If the outside was painted and the inside did not get block filler and paint until later there would be a moisture build up in the block. The heat from inside would push the moisture out through the exterior of the block. I'd be surprised if the paint is holding very well on the mortar lines closer to the top of the building.

Boyfromthenorth

If the product had any kind of epoxy in it (Which many block filler type products do) that stuff chalks in the sun. Even most two part epoxies will chalk and fade outside. But if this was inside, I'm not totally sure.

NACE

Loxon has both a solvent based system and water based system. Solvent based, alkyds or epoxies chalk in the presence of UV. Alkyds film is effected and compromised, epoxies chalk but the film is protecting the surface. Aesthetics are effected with epoxy but not the protective qualities usually. Acrylics, which it sounds like is the topcoat or weather exposed, usually are much more UV stable, have better sheen retention and chalk resistance. Some companies use to emulsify alkyd resin into their products for better adhesion and penetration to a marginally prepared surface, however they would chalk a bit even though they were latex or acrylic. Sometimes if there is a very high pH in the block, that alkalinity will migrate out to the surface, and supponify, or effectively be burned by the high pH. The Loxon system is designed to be breathalbe and allow moisture or vapor transmission. Check the pH of the surface with distilled water and pH paper or pool test kit. If the pH is high, the chalking may be a result of this. Also, why hasn't the block stabilized and acclimated after 4 years? Is there a moisture problem in the block, or was it coated when the block was not fully cured or wet? Powerwash the block with low pressure and a pH neutral degergent to remove chalk, mildew, dirt, etc., prime with a alkalai resistant latex primer, and topcoat with a top quality 100% acrylic latex. What area of the country was this in, and what exposure is the primary chalking occuring? Is the chalking happening equally on north, south, east and west? Please excuse poor spelling.