Window Rot Repair

The purpose of this page is to educate and arm homeowners with some awareness about what really causes wood rot and deterioration.  Knowing what to look for and being proactive by inspecting them regularly can be  the ticket to preventing thousands of dollars in damage.  South Louisiana's climate is hard on exterior wood.  Windows sweat constantly in the summer mornings, only to then be heated up and baked by the sun.  All of this happening in the same day.  The expansion and contraction this creates allows joints in the windows to open and the opportunity for rot to take hold.  

Two things worth noting at the top of this page. First, keep your sprinklers from spraying your windows. On newer windows that sit low to the ground and front picture windows, I see this often. Second, try to keep plants, trees, and foliage from bouncing rainwater onto your windows if possible. All the microorganisms that are eating and living on that plant would love to snuggle into the easily edible wood of your window. If either or both of these above conditions are unavoidable, they should be inspected and sealed/painted if needed routinely.

Understanding Rot and wood decomposition

Microscopic fungal spores, including mold, are continuously floating in the air and landing on your windows.  Have you ever seen a mushroom growing out a window?  I see it all the time.  Normally, with a good quality paint job that is doing its job and keeping the window good and sealed, these spores will come and go (another important reason to wash your windows yearly with a mold killing detergent).  But over time as a wood window naturally expands and contracts, often times wildly with south Louisiana's climate, gaps between joining pieces of wood begin to form.  The picture to the left shows a typical spot of 2 pieces joining where  gaps tend to form through the seasons. The same spots on doors, where the stiles (vertical piece) meet the rails (horizontal piece) at the bottom, are prime real-estate for organisms that cause rot. For puttied windows, the corners will crack first as the putty dries out over the years, which allows water to enter the joints.

If this area stays damp enough over time, the spores will begin to grow.  In the above picture, the paint film has stayed intact but left some clues in the form of small depressions and discoloration.  It will also be soft and punky and will usually depress with finger pressure.  As the fungal spores grow inside the wood, they will begin to eat and feed off the wood fibers.  By the time its really visible to the untrained eye, the problem has been growing for some time as you can see to the right.  It amazes me how fast new windows and doors, installed and painted by someone with no knowledge of how to protect them, can rot.  I've been out to homes less than 5 years old where a majority of their windows had some degree of rot.

   Epoxy repairs can be a cost effective solution if the integrity of the hidden tenons that join the window or door together has not been structurally comprised past a certain point. If the structural integrity of the sash is compromised, it’ll need some new parts, or a new sash will need to be made.  A fixed window such as a picture window is almost always repairable.  Always inspect the corners of the window sashes (first picture), because this is where 90% of repairs are needed.  If you see soft spots, depressions or indentions, discoloration, or organisms growing on or out of it, repair it sooner rather then later. It only gets more expensive to repair and isn't possible after a certain point.

If your windows are from the 1940’s-50’s or before, there’s a good chance they were made from old growth cypress.  Wood of this age has tight growth rings and natural defenses to combat fungal decay.  All the more reason to restore your old windows.  They are truly irreplaceable and will long outlast us with a little attention and love.  Just because a window is new, doesn't mean it is protected and will last. At the same time newer farm growth cypress, or any exterior woods such as spanish cedar or mahogany, isn’t doomed to rot and failure.  New windows just need maintenance and inspection.  Even if it is just an inspection every couple years, a knowledgable professional or homeowner can easily keep an eye on things.  Simple maintenance is much more cost effective than crossing your fingers and dealing with whatever problems arise every 15 years or so. 

   I've repaired hundreds of rotting windows over the past 20 years and always check on them after a year and a half or so to make sure the repairs are holding up.  But the best defense is you.  Keep your windows clean and sealed with top of the line premium quality paints.  Make sure things such as sprinklers aren't hitting the windows (a very common problem) and that plants are a safe distance away.  Most importantly, if there is a problem, hire a specialist that knows what they are doing when it comes to windows. I repair so many poor repairs and hear things like “well, the painters said they fixed it”.  Do it right the first time, and have someone looking out for your windows for then on.