Hi, we have (mostly) finished building our house, and I have a problem. We have lots of woodwork in our home including wood windows, and we have used Danish oil as a finish (interior). Unfortunately, I did not get all the windows finished before we had a terrible bout of cold weather and due to condensation and me not seeing it in time, the windows I had not gotten to have mildewed and stained terribly. I have cleaned them well and removed all the surface mildew. I tried bleach to get the actual “penetrated” stains out, to no avail. Anybody had any luck removing stains like this? I hate to paint because all of our interior trim is cypress, but the black stains cannot stay. Any suggestions? Thanks in advance. View Image
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Try a deck cleaner and brightener product. I would use it quite diluted, as it's pretty strong stuff. Just brush it on, and follow directions for neutralizing. You'll have to sand afterwords, but let the wood dry for several days first.
Sand it.
Oxalic acid, the stuff in many deck cleaners. (Others are nothing but chlorine bleach -- not very effective here.)
Sometimes oxalic acid is available from paint specialty stores under the name of "wood bleach".
It looks like your house has high interior humidity with low outdoor temperatures. Can you do something to reduce the amount of condensation? That's pretty serious water damage.
That being said, Danish oil isn't known for it's anti-fungal properties. If the humidity problem remains as-is, you're going to need a finish that can withstand long-term interior moisture exposure.
Actually, that's about what
Actually, that's about what would be expected in this part of the country, especially in a new house which is still drying out.
So what do you use for a clear interior finish?
I'm thinking one of the spar varnishes. Something like Man-O-War.
Around here you need to avoid clear finishes on window sashes, because of the staining problem.
My email has been changed from [email protected] to the present
I'd try sanding
I'd try sanding first--sometimes these stains are relatively easy to remove with a light sanding, but there is no way to know until you actually put sandpaper to wood. Sand carefully since some of what looks like solid clear grained wood is most likely a veneer.
You will quickly find that sanding a lot of windows is time consuming and it will speed things along if you have a sanding block sized for each area being sanded. In general my sanding speed is twice as fast if I have a properly sized sanding block....your milage will vary :)
As for the chemical products, I can't say how well they will work but just make sure you aren't making things worse during the application.
Best of luck