Knockdown Texture Patch - Flashing?

mseneker

I'm on the way over to look at a ceiling patch where the paint is drying darker over the knockdown patch than the older part of the ceiling. The entire ceiling was painted. My drywall material rep. is meeting me as well.

Facts:

The original ceiling was painted and the older knockdown was not very consistent in pattern before we started.

The entire back of the house has windows and natural light shines across the ceiling. The darker effects shows up as well at night with the ceiling lights on. The darker area is the entire patch, not the seems.

The drywall patch and knockdown on the patch now matches closer to the older knockdown.

On the original patch work, we could see where the plastic was placed on the ceiling and textured or feathered up to. We did the finish work and texture once again, taking extreme care not to leave edges and feathering out the texture towards but not up against the plastic.

The entire ceiling, after the original patch work, was painted by a painter with a spray gun. I'm not sure if primer was used first.

A small patch in a bathroom, with the same conditions as above, came out perfect. There is no window in the bathroom and lighting is typical. That ceiling nor any other was skimmed first.

Results:

According to the homeowner they painted over the patches 4 times with the same ceiling paint and the patch dried darker.

I'm now researching if I have a material issue in that the older texture material compared to the new has a porosity difference and therefore caused the paint to dry at a different rate. Therefore caused flashing.


Once we figure out the root-cause, we will address the fix. Anyone had a similar issue? I have never heard of a porosity difference in the actual knockdown material. We will shine a bright light on the patch to make sure it is the same color as the rest of the ceiling.

__________________
http://www.alliancedrywallservices.com
email: Alliancedrywall@hotmail.com

Tim0282

Doesn't sound like the patch was primed. You have the old ceiling with more coats of paint on them every time you paint. Try just priming the spot and putting a couple coats on just the spot, then go over the whole ceiling. I think it will always look darker (flash) on the patch if not primed and painted twice before painting the ceiling. Better off to skim the ceiling smooth, the texture.

mseneker

Tim, I agree it is always better to skim the ceilings then texture. I usually give a customer a two part bid, one for just the patch blended the best we can and the second to skim the entire ceiling.

I checked the patch. The entire back of the home is windows. The old knock down texture is not uniform. We had to blend the best we could. Now light is shining across the ceiling from the windows and there are shadows in the patch. The worst is a basement patch that was round. You can see the round patch and the best I can do is feather it out in different directions to break up the shadow or skim the entire huge ceiling which the customer has already painted one.

__________________
http://www.alliancedrywallservices.com
email: Alliancedrywall@hotmail.com

taper71

Just throwing this out there , but if you used fast set for the patch, maybe it reacts with the piant to show up darker some how. I can't figure any other reason other than different mud than the orijinal.

Tim0282

Knockdown texture is just really hard to match. There are some days I can nail it and others it seems impossible. I feel your pain!! It is tougher when you are trying to match some body else's work. When it is your own at least you know what kind of mud you used and type of hopper or sprayer and about the air pressure. You gotta love the game...

thom

If the old ceiling had several coats of paint on it, the edges of the texture will be much softer than the edges of the new texture. The hard edge on the new texture will produce more visible shadows which will make this area look darker.

Spraying tends to leave the texture edges sharp while rolling and/or brushing tends to soften them up.

I would roll or brush a couple coats of a heavy primer over the new area then a couple coats of paint. Let thoroughly dry between coats. This is a real pain because it's about 4 trips to do 2 minutes worth of painting and an hour of prep and clean-up each time.

mudmaster

yea there is a video on knockdown patches were the guy tells how not to have flashing its the one with the bald guy in the big truck. hope this helps

mudmaster

oh its on youtube sry