Exterior paint bubbling - painter says clapboard's delaminating

My house was painted last spring. The painter sprayed one coat of SW Superpaint over 30 year old clapboards. Prep was basic and minimal, but he did scrape off any flaking paint and primed all bare wood. There are now numerous bubbles from 1/2" to 2" diameter all over the clapboards. (No such bubbles exist on the trim where he brushed on Duration) When you peel off a bubble it is clear the paint is not only taking the under coat(s) and primer, but a layer of wood also. He says the paint is doing it's job and that it's the wood that's failing. Is this possible with only 30 year old clapboard? I think they're cedar but not sure. What's disturbing is a moisture meter is showing a high moisture level, yet I have a new roof, the gutters get cleaned 2x year, and I run a dehumidifier 24/7 inside and have no moisture issues inside. First he blamed internal moisture, and now he's saying it's the wood. The job is still under warranty, but he's starting to seem like he wants to wiggle out. Any help is greatly appreciated!

 

It's moisture for sure if it's bubbling off.
Lot's of things can cause it.
No moisture barrier on the ground if there's a crawl space.
Double vaper barrier under the siding.
Impropper roof venting.
Paint and or primer was applyed while there was still dew on the wall.
Paint was applyed to soon after it rained.

Peeling, Cracking - Sherwin-Williams

 

Sometimes, no how matter much prep you do in painting you will get blisters. Sometimes, in prep you miss something here and there and you get blisters. If you are getting blisters all over the place, he likely missed a step in the prep all together. Personally, I've seen this happen more in situations where people scrape, sand and forget to dust the surface down before priming. Air gets attached to specs of dust under the primer and expands when the surface gets heated up during the day. Sometimes they don't present themselves until the second coat goes on.

It is very common if blisters occur, that they will take both layers of paint off with the primer and bring the surface right back down to the wood. Sand, dust, prime, paint and paint.

I find it unlikely that the wood is failing.

 

Thanks for the replies. A few more details...

The house has a full basement. Don't think it has a double barrier on the siding. The roof is new with full ridge vent and an edge vent system (forget what it's called). It did rain before application. As I mentioned, the moisture meter is off the charts. Could the paint retain the moisture for a full 12-13 months?

Also, when scraping off the bubble, it not only is taking the bottom layers of old paint and primer, but a thin layer of wood. That's what the contractor is pointing to as "proof" the issue is the 30 year old clapboard and not the 1 year old paint job. I'm not looking to screw him over if that's the case, but I also don't want to get screwed if he's trying to pass off on his responsibility.

 

I've seen cases where the siding was what the Sherwin Williams rep called mill hardened.
The fibers were compressed and could not soak up the primer to bond it.

House Painting Tips and Hints - How to Make Your House Paint Last Longer

 

Paint bubbling is almost always a moisture issue but I don't understand the paint taking wood with it. If the primer is still stuck to the wood I'd tend to agree with your painter. Has the SWP rep come out to inspect the job? I'd like to hear his input.

Care to post a pic or two showing the bare wood and the backside of the primer - http://www.doityourself.com/forum/el...-pictures.html

btw - welcome to the forums!

 

Hope these help. And thank you everyone who's trying to give me info.

Two photos. One of two bubbles he scraped off with a putty knife. I did watch him carefully pull one away from the siding and saw the "wood" on the back side of it and bare wood where I would have expected primer to be. I also provided a shot of 2 small chips I found on the ground.

it may be important to mention, the bubbles seem to come out in the heat of the day in the sun. Moist days like today I don't see them very much. If that makes any sense.

 

So it's a masonite or some type of manufactured siding? not real wood. I believe it's a siding problem
The paint might have caused the problem to come to light. The fresh paint/primer sealed the siding and took away all easy exit points for the moisture but I don't believe it's the paint [or painter's] fault. It would still be nice to get the opinion of the paint rep.

 

How can you tell it's manufactured siding? Much of it has wood grain like real wood, or is that manufactured also? What's the likelihood the SW rep will give an honest answer if it is indeed the paint? He's not going to blame his own product, is he?

 

The backside of the chip looks like masonite and the peeled areas don't look like wood. I'm just going by the pics and your discriptions - it's possible I'd have a different view point if I were to inspect it in person.

Most of my dealings with paint reps has been fairly forthcoming. While they are predisposed to promote their products and stand by the painting contractors that use their coatings - they do want to see their coatings preform well and customers satisfied. I've had them replace defective products but they're not shy about pointing out any issues with the application either. You might try and get a competitor's rep out and look at the job but they wouldn't be as eager to come out as an SWP rep would.

 

Thanks for your input. Had the SW rep out today. Both rep and contractor think it's wood siding and not composite. The rep says moisture is causing the issue, but has no knowledge as to why. Although in many areas where new bubbles had formed had readings in the 15-20 range on his moisture meter. There were a few areas we found that were in the mid 30s. He showed me where if you pried a board out with your fingertips a bit, the moisture was evident on your fingertips. It's been raining a lot here and the bubbles come out after a rain when the sun beats down on the house. I'm having a tough time accepting it's a house issue. Roof is just a few years old. No moisture inside. New quality windows. Never an issue with the previous paint job, which was a much higher quality prep/paint job overall.

Both rep and contractor are recommending shimming under the clapboards with " Wedgevent" wedges. I can't see how that can be worth the expense as that can't do anything near the nailing points. I also worry about air infiltration if I go that route. The rep suggests a slow curing oil primer and then a Superpaint top coat. The original job was done after heavy rains in hot sun. Paint was applied within hours, if not minutes, after the primer was applied. The contractor cut corners at every turn and I can't help but think that's the issue here. This is becoming a nightmare.

 

This definitely reads as a "house issue" to me.

While there are a few more considerations moisture ALWAYS travels from a place of high moisture to a place of low moisture. Depending upon the climate where this house is located it is entirely possible that the moisture of normal living; breathing, cooking, bathing and the like could travel into the walls from the interior and "take up residence" inside the outer walls. This is especially true is a "non breathing" paint severely restricted the moisture flow through to the great outdoors. Once the outside temperatures started to warm up this trapped moisture would attempt to get outside. If there are any flaws in the paint layer this is where the moisture will exit. If there is any new paint the exiting moisture will likely lift the paint.

Ventilating the wall space IS often a most effective method to clear this moisture, which if left will decrease the effectiveness of any insulation and lead to wood rot or the growth of mold. If I had any of the symptoms you have described I would definitely try the wedges to ventilate the wall cavities and allow the siding to dry thoroughly before repainting. Your painting contractor may not have used the best techniques on his original job but the paint company representative is giving you good advice in my opinion.

 

How old is the house? Do you know anything about the insulation and whether or not the walls have a vapor barrier? Often on older homes without a vapor barrier it is beneficial to use a latex primer instead of oil base. Because latex doesn't seal as well as oil base it allows the house to breathe [exhaling the moisture better]

SuperPaint isn't the top of the line but is a very good coating. Once SWP came out with the SuperPaint line it is what I almost always used on the exterior until I retired. It is never a good idea to rush top coating over the primer but I'm not sure that it has much [if anything] to do with your peeling issue.