Here is some expert advice for homeowners from A Brush Above Painting in Boone, North Carolina.
Mildew weakens exterior wood by feeding on it. As the mildew grows, it damages wood — first cosmetically then structurally. Replacing rotted or damaged logs on your home caused by mildew is very expensive, regardless of who does it. My advice is to have your home professionally cleaned once you first notice any sign of mildew on it.
Mildew is a living fungus, similar to a mushroom or even a blade of grass. When mildew gets on or in your home, absolutely nothing good can come from it. Mildew will cause wood to rot faster than anything. So, when you see mildew on your home, you need to have it removed. If you see black or grayish mildew on your home call someone to kill the mildew. Most people think that cleaning their home with a pressure washer will rid their home of mildew. Nothing could be further from the truth. Water will not kill mildew. Use TSP (trisodium phosphate). Do not use BLEACH, it will kill mildew and everything else it touches like plants, flowers, grass, and can actually harm the wood on your home. Also, bleach is very toxic. The single biggest mistake I see homeowners make is simply waiting too long to have their home cleaned until it is covered with mildew. Once this happens, you will more than likely have bigger problems than mildew, such as replacing rotted wood siding, decking boards, etc.
Pressure washing log cabins or log homes — I have preached against this practice for years. Here is why. If you have cracks in your logs or places where your caulking has failed, water will be forced into these areas from a pressure washer and run down the inside of your walls, leaving water stains which are very expensive to have removed. Water is like electricity; it will find the least resistance and go there. So the least amount of pressure that is being applied to your logs or siding the better. I use a back pack sprayer to clean everything I paint or stain. Pressure washers are good for masonry and decking and hand railing. However, be careful. It is very easy to fur the wood on your decking and hand railing. And more often than not, you will leave stop and go marks in your wood. Bottom line here folks is to have your home professionally cleaned once a year; it will save you in the long run.
The second biggest mistake I see homeowners make is buying bargain paint, compared to Sherwin Williams or Benjamin Moore. Sherwin Williams and Benjamin Moore have chemists who constantly modify their paints and stains. And both of these companies have been around well over a hundred years. My point here is you get what you pay for. If you are having to repaint or restain your home every couple of years, your are either using the wrong paint, paint contractor, or both. Finally and most importantly, this advice is free - check contractor's RECENT references before you hire them. While there are some very good paint contractors in this area, I assure you there are equally as many fly-by-night contractors who will throw an ad in the local newspaper, get hired, and use the cheapest products money can buy. And when the paint job fails, the contractor is nowhere to be found. Then you have to start the process all over again. And correcting a bad stain job on a cabin or a log home can be very expensive. These are the very best preventative maintenance tips I can possibly give you concerning mildew and quality of stains or paints. Read on as I address Log Home Caulking Tips.
Log Home Caulking Tips: If you are the proud owner of a log home, you may have heard about caulking or chinking your home. While chinking is generally for gaps in the log seams that are larger than three-quarters of an inch, you can safely caulk your home if your gaps are smaller than that. Just be sure to use a quality caulking such as Lexel. Caulking is a good way to cut energy costs and improve the aesthetics of your home.
Why Caulk? If you have even small gaps in your log home, you could be losing energy like cooling and heating. Though they may not seem very large, you can see the difference caulking makes on your energy bills. Caulking is flexible, which gives your home plenty of space to expand and contract with the changing temperatures, with less cracking and checking. It also gives your home a much neater appearance. Even if your home was hand-hewn and the logs fit together properly, a neat application of caulk can make all the difference in showing off the lines and texture of your home.
Application Tips: When you're ready to caulk, evaluate the size of the gaps between the log. If some of them are larger than your bead of caulk, it's a good idea to stuff the cracks with a backer rod. Backer rod is a foam strip that will fill and insulate the gaps so that the caulking does not have to fill the entire gap. It is a solution for uneven, hand-hewn logs. Allow the caulking to dry for 24 hours before staining. Your investment in time and money while caulking your home will come back to you tenfold in your energy savings and aesthetic appeal.
Where Not to Caulk: NEVER caulk checks or cracks in your logs unless they run directly into a door or window seal, or the checks or cracks are so big that they hold water. Water, like electricity, will run downhill, and if the checks or cracks hold water, the water will eventually find its way inside your home leaving water stains on the interior of your walls that are very hard to get rid of, even for me.
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