One few more questions -- the contractors who have come to the house have suggested that this job will take 2 days. Is that reasonable? I assume that a primer has to be used and then a couple of coats of paint. How much time must the primer dry before the paint is applied, and how much time must pass between the 1st and second coats?

It looks like you have some serious moisture issues. What is behind the wall, a bathroom? The moisture needs to be addresses first, otherwise you will continue to have the peeling.

All loose paint needs to be scrapped and sanding is need to bring back fresh wood on the weathered siding. Yes, prime first. When was the house built? Are you concerned about lead paint? Test it.

2 days is reasonable under ideal temperatures.

How old is that wood? Ideally you want to scrape, sand to smooth, fill in cracks and holes, prime, and apply two coats of paint. Carlos229 is right - you need to figure out what has caused the paint to peel. I wonder why the peeling is much worse at the bottom.

Bathtub behind the wall? Some sort of plumbing leak? Roof leak? Water getting behind the siding?

Did you just move to this place? How long has this been happening?

My guess is that about 3 boards below the window is the floor level for a room above. Is this room over the garage? Are those garage doors below the siding?

As the above posters have stated, you must determine where this moisture is coming from and lower the humidity level in that area, plus install some form of vapor barrier on the inside walls. This can be a primer with low perm perm rating and quality paint on the walls. If it is bare studs in a garage, install a vapor barrier and dry wall the walls

My wild guess is that this wall faces East. Rapid rise in temp from cold nights to rapid exposure to morning sun can cause big problems when the siding is saturated with moisture internally. The moisture wants out NOW, and will push the paint right off the siding!

If this is a garage below, is this a cold ,snowy climate? Are snowy cars being parked in the garage over night? A lot of snow melts off a car that is parked with a hot engine in a garage. Where does that water go? Fire codes require that at a minimum there be a fire rated ceiling in such a garage area, but not the walls necessarily, or maybe a single layer of drywall with no vapor barrier. The ceiling would also be insulated, which would form a minimal vapor barrier at the floor level, thus lessening the affects of moisture at the floor level.

Is this an older home that had many coats of oil paint in the past, followed by a coat of latex in later years. Acrylic paints bind firmly to old oil paint, unfortunately, acrylic paints expand and contract with temperature/humidity swings and oil paint does not. Oil paint is initially quite brittle and becomes more so with age. There are documented cases of massive peeling due to this scenario. The well bonded acrylic paint rips the non-expanding oil paint from the wood siding.

One way of the other, the more you get down to bare wood or solid old paint, the better. A full prime coat followed by a couple coats of an acrylic house paint should alleviate the problem.

Have your bids included lead testing? Any sanding or scraping of more than 6 square feet of lead paint requires tenting and sealing off the area by Federal law.

Is the whole house going to be painted in 2 days? That would seem quite quick. However, the failed area could probably be done in that time.

Looks like lead paint! Seal and treat prior to prepping and then seal once again by treating any remaining lead paint. Easy application by actually treating lead as opposed to simply hiding it with paint. Yet all for the same cost as paint! Ecobondlbp.com

How does one treat lead paint?

Apparently there are products that can convert lead compounds to a non-biologically absorbable form:

www.lockuplead.com

www.lockuplead.com/lead-neutralizing-bonding-primer

Thank
you all so much for the comments. Below
the wall is the garage. It stays open (even
during the winter). The house is in the
Washington, DC area, so it doesn’t get that cold. There is snow, and there are cold days, but
the winters are usually not severe. The
room behind the wall is a study. My
understanding is that the garage and the study may have been built as an
addition after the house was built. The
study isn’t well insulated, so it is hot in the summer and cold in the winter. The wall was last painted around 2005. My vague recollection is that there was some
peeling generally in the same area back then, but nothing like it is peeling
now. It wasn’t scraped and sanded --
pretty much just painted on top of it. I
don’t know whether it was primed the last time it was painted, or whether it
was oil or latex. There has been a
problem with the gutters that I am about to address. I’m afraid that I don’t really understand
the moisture issue. If the problem is
with the gutters, why is there little/no damage along the top half of the
wall?

Because there is no sun hitting the top boards. The sun draws the moisture out, and when there is no escape for it, it will try and go through the paint, which causes bubbling, peeling and massive paint failure. When we speak of moisture in this way, do not think of it like water from gutters. It's more like water vapor that is trapped behind the siding. Normally, this is able to escape underneath each lap of siding which is why we don't caulk that gap and is also why you see little weep holes in aluminum or vinyl siding.

Oh, ok, thanks. But are you saying that the water vapor that is trapped behind the siding is coming from someplace other than the gutters? If it's not the gutters, what could it be? As I said, the room with the window is a den (thus with no running water) and below is the garage.

I Don't think it has anything to do with your gutters. Nor do I think the problem is the room above. My guess is that those boards with the extreme peeling are actually on the outside of the garage area. Do you park in the garage and do you close the doors routinely? You drag in snow and moisture on your warm car and then close the doors. Where does that moisture go? It goes to the backside of those walls where it condenses or freezes. Are there what looks like reddish water staining on those walls? Are the garage walls bare studs and sheathing? Drywalled but no insulation or vapor barrier.?

Also, if it is an older home, there is probably no vapor barrier under the concrete floor. Another source of moisture working its way up from the ground.

My guess is that the garage ceiling is drywalled and insulated. The drywall is required by firecode. This limits the amount of moisture that enters the living space above. My advice: if the walls in the garage are not drywalled, do so with a visqueen vapor barrier behind the drywall. Even if the studding and sheathing is left exposed, prime it with an oil based primer and then put on a finish coat of vapor limiting ( low perm rating) paint.

Airborne moisture is getting to the backside of that garage siding and into the wood itself. The sun beats on that siding and creates vapor pressure in the wood. That vapor pressure literally pushes the paint right off the surface of the wood! By whatever means, you have to stop it.

The garage isn't drywalled -- it's cinderblock. I can't tell what the ceiling is. It doesn't seem like drywall. It's textured and it feels like plaster or some other material. I park in the garage, but the door is never closed. Does any of this affect your analysis or what I should do?

If you decide to do nothing but paint, you should check under each lap of siding and see if that gap is caulked or closed. It needs to be open so that moisture can escape. There are even vents you can buy that you stick under each board. Also, an acrylic primer would be best and flat paint. Anything that creates a seal is going to peel sooner. Sometimes we just have to paint every few years if going through the process of actually fixing the moisture issue is deemed not worth it.

If the cement block is not painted, it should be painted with a block filler primer and a quality finish coat. The block filler primer is a heavy bodied paint which will seal all those little cracks in the texture of the block. Cement block is very porous and will pass moisture readily. Am I right that the block goes up to about where the gross peeling stops? There is a high ceiling in the garage that goes up about 4 feet above the garage doors?

Actually, the fact that you don't close the doors should be beneficial, since it equalizes the humidity on both sides of the wall. Moisture attempts to equal the moisture level on both sides of a permeable wall. The fact that the heat is approximately about the same inside and outside the garage tends to argue against my theory. In cold climates, warm, relatively humid air tries to move from the house to the cooler, relatively drier outside, but gets hindered by the siding on the house.

That being said, I still believe the source of the moisture is that being passed through the cement block and getting trapped in the siding. It would be interesting to know if there is an air gap between that interior block and the siding, and if there is a vapor retarder such as felt paper between them?

The cement block isn't painted. Is there a particular brand of block filler primer that I should use? Do you have a recommendation for the quality finish coat? Actually, the room above the garage is quite hot in the summer and quite cold in the window. I was wondering whether I should have the garage insulated. Should I prime and paint it before doing that? Would insulating it make the moisture problem worse?

The ceiling isn't high -- not 4 feet above the garage door. The ceiling is about 8.5-9 feet high. The top of the garage door is 7 feet high. So the block doesn't go up to where the gross peeling stops (the peeling stops about 4.5 feet above where the cinderblock meets the garage ceiling). I'm afraid I don't understand your last question.

Does the floor of the room above come down to a short distance above the garage door? What I am trying to figure out is what is in back of the peeling, walls of the study, or walls of the garage. I still think the source of the moisture is from the bottom up. The lesser peeling about half way up point is possibly because of the "cripples" in the wall. These are pieces of 2X4's that are placed horizontally into the stud cavity to keep the studs from warping, but they also hinder moisture travel upwards through the wall cavity.

Such rooms as your study are often cold as they are open on three sides and from underneath. It sounds like they scimpped on the insulation, and/or heating. If the insulation does not have a good vapor barrier, it too could contribute to the peeling. If you repaint the study, consider first a vapor retardant primer on those inside walls to help keep moisture from getting to the outside walls.

I would still advocate sealing the cement block, even for aesthetics. It will look a lot better even as it retards moisture uptake. Block fillers are made by all the major manufacturers. They are simple heavy bodied latex based primers designed to fill all that texture in the cement block. I would follow that with a coat of a low perm rating, vapor retardant primer. Again, all the major paint companies make a version of it. Then any good finish coat of house paint. If nothing else, it will make coming home to a nice bright garage more inviting. If it were me, I would also place some good LED lighting bulbs in there too, possibly on a motion sensor, so that it welcomed me when I drove in, since you apparently leave your doors open all the time.

Below the window to the floor in the study is about 3 feet. Each board on the outside is about 8 inches. So the wall behind the top peeling room is the study. The peeling boards below that is the garage -- I believe above the ceiling and below the floor. I plan to use Benjamin Moore Aura latex paint, but I don't know what primer to use because I've seen conflicting information. Some say that latex should be used if there is a moisture issue, some say that oil based should be used on exterior wood. Do you have a brand and kind of primer that you can recommend? The person in the paint store didn't give me much confidence; he couldn't answer any questions and didn't seem to know anything about painting. He suggested Fresh Start multipurpose interior/exterior primer, but I thought I should be buying primer that is exclusively for the exterior. Do you have a recommendation for primer in my case?

Since we're all spitballing here: one time I worked on a house that was doing the same thing: redwood siding from 1950 painted with oil for years, then repainted with latex, and the paint peeled down to bare wood in sheets. Seems like the combination of layers and age and wood and moisture all played a role.

I would strip to bare wood, use a moisture meter, determine if it was redwood, prime and paint accordingly. The redwood institute (or whatever they call themselves) has a good list of proper painting practices.

Fresh Start 046 is what you want, not the multipurpose. It's more expensive but it has better adhesion properties and actually kills stains which you are likely to have.

Redwood is loaded with water soluble tannins that bleed through reddish stains to the finish coat when not primed with an oil based primer ( same as with cedar, only worse). There are now water based primers that claim to stop tannins if given 24 hours to cure before painting. For whatever reason, over the years, it always seamed to me that redwood siding did not hold paint as well as other woods I think it was used due to its natural rot resistance..

Here is another theory: homes that have had years of oil paint and then an acrylic is place over them can have drastic peeling. Why? The acrylic bonds to the old brittle house paint. When the sun shines on the surface, the acrylic expands and contracts, but the old oil paint does not. The result is that the new latex paint pulls the old paint right off the surface. Obviously, the poorer the original bond, the more likely this is to happen. It is possible that there is a combination of causes going on here.

F

paintguy22, Fresh start 046 is the all-purpose primer. Are you thinking of the 094 wood primer?

For what it's worth, I used the 046 high-hide all purpose primer on my exterior because I had a mix of stucco and wood and I wanted to use one primer for all. I thought it was great, easy to work with, stuck like crazy, and covered really well. My wood was in horrid shape with areas where the paint stuck and others where it scraped off to bare wood. After I scraped and sanded everything, I primed and finished with two coats of Aura and I am VERY happy with the results. I can't quite recall, but I may have used two coats of the primer on the sections of my wood siding that were really bad.

This is all so helpful. Thanks for all of your input. I am also
working on the exterior wood shutters. I have taken them down, sanded
them down
to the bare wood, and I'm now ready to prime and paint them. Since they
are wood (and there is no vapor barrier issue), should I use an oil
based primer or could I use the latex? If I used an oil based primer,
can I still use the Benjamin
Moore Aura water based paint, or would I have to get an oil based paint
as well?

Jelly, 094 is alkyd. You can use any paint over oil based or acrylic primers. For wood shutters, I would use oil. Fresh Start 094 or the Moorwhite 100 which is slower drying. The longer the dry time, the better the primer can penetrate and grab hold of the wood.

Thanks. Actually, given the slats, I thought it might be easier to spray prime and paint. Is that an okay option? The primer would have to be something standard from Home Depot as opposed to Benjamin Moore.

I think it would be ok to use a spray can to make it easier to do the slats, but primer should be brushed into the wood so that it can penetrate. Also, primer in a spray can is thinned down so that it can fit through the little hole so it's not as good.

That's really helpful. Home Depot sells paint sprayers. Do you have any experience with that? Are they easy to use with standard paint?

The cheap hand held sprayers do not spray heavy bodied paints or primers. If you thin the product enough so that it will spray, its integrity has been compromised. The hand held Graco sprayers will spray heavy bodied latex or oil paints, but the price range is about $180 to $270.

Simple air compressor powered siphon guns will also not spray heavy bodied paints or primers. Even if they did, they require large compressors capable of delivering large volumes of air.

If you only have a few shutters, you might consider the spray cans of CoverStain, primer which is rated for exteriors. This is a quick dry oil primer. One trick I always use by spray cans is to heat the cans by putting it in hot water as hot as it comes out the faucet ( about 125 degrees). This increases the pressure in the can so that it sprays better. Being an oil product, the viscosity of the primer is also lowered, so that the l.ighter liquid simply sprays better.

Paint sprayers take practice. Some people pick it up quick and others just can't. If you are going to play around with it, place the shutters flat so that you will have less of a chance of paint sags.

Ok, I've abandoned the idea of a sprayer. I bought Benjamin Moore wood oil based primer. I am also about to buy block filler primer. I'm choosing between Benjamin Moore Ultra Spec Hi-Build Masonry Block Filler Flat (571) or Zinsser Block Filler 2X Primer. Is it worth the extra money to buy the Benjamin Moore?

Zinsser doesn't make any bad products. It is a good mainline company without outrageous prices.

This is a project I'm starting tomorrow it just takes a lot of sanding start out with like a hundred grit go all the way down to 220 grit if you wanted to be really nice but it's going to take a lot of sanding to get the way you want it

It's just going to take a lot of sanding this is a project I'm starting tomorrow I plan on using 80 grit going all the way down to 220 grit to make it very smooth that's the best way to do it