We often get asked about some practical cold weather painting tips! Most homeowners are deeply concerned about when is a good time to start painting, especially coming off a cold winter!
We have thought of several great tips to keep you out of trouble! This is list is partially inspired by about.com’s great list, so thanks to them for their practical tips! It is important to understand how really low temperatures can affect paint application and how it changes the drying pattern, characteristics and performance of the paint. Cold weather affects painting because alkyd and oil paints are based on natural oils and resins that at low temperatures become more viscous. So when painting in cold weather, or even at subzero temperatures, some paints, will become very thick or semi-solid that might require excessive thinning. However, latex paints will freeze at low temperatures, requiring some special additives to improve freeze/thaw resistance in paints. These same additives could be used for hot weather painting making easier the brushing and rolling process. Latex paints are affected solely by the slower evaporation rate of water and volatile additives at low temperatures.
Cold Weather Painting Tips: Bad Paint?
Latex paints, as we explained earlier, might freeze and thaw, if they are not treated properly. Nonetheless, how can you paint if the product has gone through several freeze/thaw cycles? If that’s the case, and if you are planning to use that old latex gallon, you might want to check if the paint has become lumpy. When such consistency is observed, then that paint is no longer usable. Latex paints are manufactured to undergo a limited freeze/thaw cycles, but at this moment that paint should be discarded.
Cold Weather Painting Tips: Recoat
Cold weather will slow drying time and will extend your recoat times. Recoat time, using latex paints, at 75 degrees Fahrenheit requires a period of four hours. If the temperature drops to 50 degrees, then the recoat time will be extended to six hours. Painting in cold weather using alkyd paintswill require even more time, in some instances more than 48 hours before recoating.
It is important to note that the surface temperature can vary between different areas on the same structure causing the dry time and proper film formation to vary as well.
Cold Weather Painting Tips: Problems
Painting in cold weather might bring additional problems such as:
- Poor color uniformity
- Heavy film might slow down drying period
- Paint will require more mixing time
- Water spotting problems, especially Latex paints
- Improper film formation causing a powdery film
- Touch up coat might look lighter than the base coat
- Excessive film building up might reduce your paint coverage
- Oil based paint should not be applied when temperature is below 40 degrees
- If the room temperature is raised to create better environmental conditions, premature skinning of the surface might occur
- A latex paint film that goes under freeze-thaw cycles during the first two weeks of cure may shorten the long-term life of the paint system. If you have no other choice, than painting in cold weather be sure to:
- Verify that the paint manufacturer recommends the paint for your specific temperatures
- Check the wall’s temperature with a non-contact infrared thermometer, too, not just the air temperature
- Choose the right roller and brush depending on the temperature and paint consistency.
- Paint between 10 a.m. and 2 p.m.
- Set up scaffolding, wrap everything and heat the area.
- Use cold weather coatings and do not paint if the temperature will be below 35° F for two days after painting.
- Make sure you use a good bonding primer before applying paint.
Always, keep in mind that your best bet is calling a professional! Feel free to give us a call anytime and we will be happy to help keep your home’s paint shining and beautiful.