Question: I am having a problem keeping paint on my porch floor. The porch is tongue-and-groove pine, about two years old. The boards were primed on all four sides, before being installed, with Benjamin Moore white alkyd primer.
After installation it was painted with Benjamin Moore alkyd porch and floor enamel. After about three months, the paint started cracking and peeling down to the bare wood. the dealer suggested sanding the floor down to the bare wood where it had peeled off and repainting it without primer. We did that.After several months it peeled again - in addition to peeling in more places on the original paint. We called Benjamin Moore's lab. It said they have a bonding primer (M1575) that doesn't dry but can be painted over in 20 minutes, then painted with an epoxy ester (M-2574).
We had a factory representative look at the porch and he said the lab's idea wouldn't be appropriate. He said to again sand the peeled places and repaint with the porch enamel thinned about 25 percent.
He also thought the problem might be moisture, but the ground underneath the porch is like fine powder and completely dry.
Sanding and repainting the porch is a lot of work and expense. Since we've already done this once, we decided to write to you to see if you might know of a reason for the peeling paint so we might correct the problem before we do all the work again. - J.J., Evansville, Ind.
Answer: I agree that it sounds like a moisture problem. The wood may have been primed and sealed when the wood was still green.
Ideally, the wood should be dried to a moisture content of 4 percent to 6 percent before it is sealed. If that's not possible, the ends of the wood should have been left exposed at each joint to allow the wood to dry naturally, or the bottom of the wood could have been left untreated.
If sanding is not a problem, get under the porch and try sanding the bottom side of the wood.
This should allow the wood to breathe and stop the paint from peeling.
Question: We have a problem in our attic on our addition. Frost or ice forms over the nail ends from the roof.
When the frost or ice melts, it drips into the attic. The roof does not leak. There are roof vents also.
I do not have this problem in the old section of the house.
There is an opening to pass from the old to the new parts of the attic. What can be done about this problem? - L.J., Monroe, Mich.
Answer: The problem is moisture in the attic. In winter the moisture condenses on the coldest areas; this is usually the underside of the roof decking or, in your case, the ends of the roofing nails.
Your roof vents are a plus, but do you have soffit or overhang vents? Without soffit vents the attic becomes pressurized, and no air flows into the attic.
The heated air from your home escapes to the attic to make up for the air that leaves the roof vents. Air that you've paid to heat goes through the roof, and on the way out it damages the roof and the insulation.
Seal all the openings to the attic that you can find. Look inside closets; there may be cracks at the wall-to-ceiling connection.
Heated air also can escape through cracks around ceiling light and fan fixtures and through holes for hanging decorations.
Fans for the kitchen and bathroom should have ducts or vent hoses in the attic that vent all the way to the outside, not to the attic.
The hose from bath fans should be installed under the attic insulation to keep them warm and free of condensation.
The discharge ends can vent to the overhang. And the overhangs need vents to provide fresh, make-up air to the attic.
The more vents the better, but a good rule of thumb is 50 percent of the venting should be from the overhang and 50 percent from the roof.