Hi all. A friend asked for some advice on his 2-year-old deck. It’s constructed from Ipe. When built, they used Penofin oil and applied as instructed. Within 3 months the deck was turning black with mildew. After a year, he power washed it and applied another coat of Penofin oil. Again, within 2-3 months, it began turning black (see attached-I hope).
They would like a maintenance-free deck, but also want a natural finish, without the natural weathering that a natural finish will eventually lead to. I’ve tried to explain that a natural finish will expose the wood to the elements, it will weather, yadda, yadda, yadda. At this point, I think they would at least like to eliminate the mildew problem without having to powerwash the deck every year, if possible.
Any suggestions? I normally use a mildewcide when exterior staining to inhibit mildew for as long as possible, but I’ve never used Penofin, so I was hoping to get some feedback before recommending its use in this application.
And no, I didn’t build the deck. The guy who did now won’t return their calls. I’ve done some work for them in the past, so they called me, but I haven’t done much deck work lately.
Thanks.
Edit, the light spot in the left foreground is where the table normally sits.
Edited 5/17/2003 10:04:09 AM ET by NickNuke’em
Replies
What kind of trees if any hang over that deck?
__________________________________________
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
The leafy variety. It gets dapples sun in the summer, a little more when the leaves are down. I have more shade on my deck then they do and mildew isn't a problem. But I use a deck stain with a lot of solids and I add the mildecide.
A good point, though. I didn't think of the trees.
I never met a tool I didn't like!
Around here the walnut and maples drip a very fine sticky substance almost the entire leaf season. Dirt sticks to that and becomes a film covering whatever it lands on. Might the stuff you see not be something else?
__________________________________________
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Edited 5/17/2003 1:01:01 PM ET by calvin
How can you tell if it is that sticky stuff instead of mildew? My friend claims it is tough to power wash off, though he was using only water and pressure. TSP and bleach to a number on mildew, so he was going to try that, eventually; he's not thrilled with home maintenace/repairs, preferring to spend his time tinkering with his motorcycle and repairing cars.
Also, around the deck where protected by the eaves, the mildew hasn't formed. Not solid evidence of one cause or another. And although we have a ton of maple trees here, I can't recall them 'spitting' as you decriped. I know walnut trees do something similar to discourage growth of other vegetation, but I'm not sure about maples.
Thanks again for the reply.
I never met a tool I didn't like!
I'm guessing the customer cleaned his deck too early in the season, with the pollen still falling from the trees, he waited a few days for the deck to dry, then he put the stain on over the pollen.
That said, you may now (July) clean the deck, use a biowash and scrub brush on a pole, preferably on a cloudy day so the chemical has time to react to the wood, then hose off. By the looks of this deck it will probably need to be cleaned twice.
Let the deck get good and dry before you apply the stain.(2-3 days)
Good luck!
Bob
"Rather be a hammer than a nail"
Bob,
Thanks for the info. I was hoping you would stop in and offer your two cents worth. Interesting bit about the pollen, it never occurred to me it would be the cause.
Incidently, what is involved with a biowash? I've never heard of the term before.
Thanks again.
I never met a tool I didn't like!
Edited 5/17/2003 11:41:40 PM ET by NickNuke'em
Biowash is just a cleaner that is safe to plants. Ed Hume has one called "30 seconds" sold a Lowes for $8.97 per gallon. One gallon makes two. Just put it in a garden pump sprayer, scrub lightly, then rinse.
If you have a pair of old dirty tennis shoes you'll get them looking like new by the time you finish cleaning that deck :-)Bob
"Rather be a hammer than a nail"
Bare Ipe` doesn't usually support the growth of mildew and I have a hard time imagining that the Penofin contributes either.
That means that something is settling on the deck that is a food source for the growth.
Pollen was my first thought as I was reading through the posts but Bob beat me to it..
Excellence is its own reward!
Thanks for the input. I'll pass along yours and Bob's theory and recommend he wash the deck in July with a biowash, let it thoroughly dry out, then apply the Penofin iaw mfrs directions. If that doesn't work, maybe it's time for deck stain and mildewcide. Would hide the wood, but might keep the discoloration at bay.
Thanks again.
I never met a tool I didn't like!
Right about drying so he doesn't trap food and water under the seal..
Excellence is its own reward!