PAINTING WITH OSCAR
Greetings everyone, Oscar the Grotesque here, joining you for another week to look more closely at Adirondack architecture, historic buildings, and preservation opportunities.
This week it looks like Spring is finally here to stay, and summer is in our sights! It is the perfect time to start those exterior house projects. Just like your car, your house requires routine maintenance* to keep it functioning correctly, looking beautiful and preventing small problems from becoming BIG, $$$ problems.
If you own a home with painted wood siding or wood trim, the painting will be part of that maintenance program. Exterior elements deteriorate quickly without a protective layer of quality paint. Oscar always advises preservation by prevention when possible. Keeping your house exterior and trim adequately painted is imperative to the long term care of your house.
Common paint problems:
1. Alligatoring Paint
Cause: This occurs when oil-based paints have gone beyond their usable lives. As oil-based paints age, they become harder and more brittle.
To fix this issue, you have a couple of options.
- A recommended approach is to remove any loose paint and apply a filling primer that will smooth out the surface and fill most of the cracks. Then, finish with two topcoats of quality paint. (Test to be sure the old paint and new paint are compatible)
- In the case of catastrophic paint failure, remove ALL of the paint by scraping, sanding, and in extreme cases using chemicals or heat to remove the old paint down to bare wood. This scenario runs the risk of damaging wood siding and details, and any history of the original paint colors. Apply a bare wood treatment, and a good primer that is designed for the material you are planning to paint (wood, masonry, etc.) would then need to be applied then apply two topcoats of quality 100% acrylic paint. (Note: While traditional Oil-based paints have many desirable features, there are comparable choices available, many states have restrictions on the use of certain paints.)
Did You Know: When paint builds up to a thickness of approximately 1/16″ (approximately 16 to 30 layers), one or more extra coats of paint may be enough to trigger cracking and peeling in limited or even widespread areas of the building’s surface. This results because excessively thick paint is less able to withstand the shrinkage or pull of an additional coat as it dries. – National Park Service
Peeling Paint
The two major causes of peeling paint:
- Moisture issues in the substrate
- Poor paint adhesion (improper surface cleaning/prep), moisture issues (interior/exterior), and from painting over bare wood while it is still wet. Moisture collects behind the paint and breaks adhesion from the bottom layer.
Solution:
The only way to fix peeling paint is to deal with the source of the problem. There is no sense in repainting without dealing with moisture problems FIRST. The follow-on coats of paint will only fail, just like the current paint. If it is a moisture issue, find the source of the leak or moisture build-up. This doesn’t have to be bulk water, and it can be something as simple as too high humidity inside the house or as complex as vapor drives through the walls.
Once you have solved the moisture problem, prep the surface, treat bare wood, prime and apply two coats of paint.
Blistering Paint
Possible cause:
- Heat blistering caused by painting in direct sunlight on a surface that is too warm.
- Moisture blistering can be caused by the migration of water through an interior wall to the exterior, thus pushing the paint off of the surface.
- Application of oil-based or alkyd paint over a damp or wet surface.
- Exposure of latex paint film to dew, high humidity, moisture, or rain shortly after paint has dried.
- Damp basements.
- Moisture seeping into the home through the exterior walls.
Solution:
Remove all loose paint (by scraping or other methods) and sand the surface to smooth out any rough edges. Determine and repair any cause of excess moisture before repainting.
While the three above are the most common problems, you might see other issues such as chalking, when the pigments start to fade, or rust and discoloration caused Water and moisture penetrates the paint layers, and/or nails work loose or “pop” out. If this occurs: 1) Remove nails and replace them with stainless steel or corrosion-resistant nails. 2) Sand, the nail heads, countersink, prime, caulk/patch nail holes, sand smooth, and repaint.
What color should I paint my historic house?
A historic house always looks it best in a color scheme from the time and location it was created. That being said, there is a dizzying array of fun colors to choose from these days, and exterior paint is temporary. Unlike architectural features, paint is relatively inexpensive and easy to change. While period appropriate colors will compliment your historic building than some trendy colors, it really is your preference. There are numerous books to aide in selecting period appropriate colors, and for the purist paint analysis can be done to use the original house colors. Before you start purchasing, you should test your paint colors out on your house. Buy a few small samples and paint them on your home. See how they look at different times of the day. Virtually paint your house and experiment with color palettes.
Prepping to Paint
Caution: When removing old paint from before 1978, you may be exposed to lead dust. Always follow the EPA’s guidelines for safely working with lead paint.
REMEMBER THE KEY TO A SUCCESSFUL LONG LASTING PAINT JOB IS IN THE PREPARATION!!!!!!
DO
- Take enough time to prep the surface thoroughly before painting.
- Repair Damaged Wood – Make sure that any rot, moisture, nail holes, or other problems have been resolved.
- Wash – Gently, give your house a good washing. We recommend a good rinsing with a hose and a long brush to get the surface thoroughly clean. Do not pressure wash, which might cause more damage than you want if there are some soft spots. After the surface is completely dry, you can continue.
- Remove Loose Paint –Paint is only as good as the surface it adheres to, and if you paint over loose or chipping paint, it will be a matter of weeks before your new paint job starts to fall apart.
- Caulk & Prime – Make sure to caulk any gaps around siding and trim junctions. Then spot prime any bare wood or filler/epoxy repairs.
- Make sure wood is completely dry (not just the surface) before repairs, priming, and painting are performed.
- Use quality brushes
- Ensure the wood to be repaired/painted is “sound,” in good condition after sanding, and not rotten.
- Stripping Paint – Hand scrape to strip paint and/or use a minimally invasive method such as infrared heat, to minimize lead paint vaporization, fire, and wood damage.
- Use a bare wood pre-treatment!
- Paint application by “brush.” Paint is forced into the wood grain better than via a light “spray.”
DONT
- Disregard the use of Personal Protective Equipment (PPE).
- Skimp on surface preparation. The paint job is only as good as the prep! Remember 80% prep and 20% application!
- Allow lead paint (dust, chips, flakes) to contaminate the surrounding environment.
- Attempt to remove paint by “aggressive” pressure washing.
- Attempt to remove paint using any type of media blasting.
- Repair, prime, or paint wood that is damp or wet.
- Make repairs, prime, or paint over wood that shows signs of graying, rot, or damage.
- Don’t apply paint via “spraying.”
*OSCAR ADVICE: Establish a maintenance Program
Exterior Painting Information and Resources:
NPS Preservation Brief 10: Exterior Paint Problems
Common Paint Problems and How to Fix them
Exterior Paint Failure and How to Fix
What color to paint my historic house
Guide to Historic House Colors