A few years ago, I had our deck professionally stained using a Cabot, Semi-transparent, oil based stain. It looked good the first year and then started flaking. I power wahed the deck this weekend, and the flaking came off, but the deck looks terrible.
I want to restain the deck myself this summer. Do I have to use a semi-transparent stain again? Do I have to use oil based, or can I use a latex stain without having to sand the deck down to bare wood?
Thanks for your help
Re: Deck Stain
I am surprised that you have experienced stain failure with the Cabot's oil stain.I have had good results with this product in the past. Oil stains generally penetrate better than acrylic based stains.
The most common reason for stain failure, whether oil or acrylic, is not removing the mill glaze from the wood before staining. "Mill glaze" is what results when the lumber is planed smooth at the lumber mill. The planing blades produce heat and polish the surface of the wood, resulting in the pores of the wood being closed up. If the wood grain is not opened up, the stain will merely sit on the surface of the wood and not penetrate. It will look good initially, but fail by the following spring.
In years past, a new deck would be allowed to age for about a year. The sun and rain would naturally open up the grain. This is probably still the best advice. However, there are deck cleaners containing oxylic acid which will aid in opening up the grain.
Sanding can also open up the grain, but sanding with too fine a grit and with power sanders can actually create mill glaze too. Don't use any paper smoother than 150 grit in sanding.
If you are going to use semi-transparent stain, any remaining remnants of the old stain will show through, as will any other kind of staining from mildew, spilled wine, etc. To this extent, the deck surface must be thoroughly cleaned or stripped before new staining.
Solid hide stains, which are somewhat like light bodied paints, give much better protection to the wood and touch-up easier, but most people want to see the natural beauty of the grain.
As to oil or acrylic stain: I am from the old school and still prefer oil stain. Properly applied to open grained wood, it should never peel. It however, does require almost yearly re-fresher coats of oil. Acrylic stains have more surface build up and is more likely to suffer peeling, especially in such a mild/wet climate that is present in the Pacific North-West where I live.
To directly answer your questions: you can use either oil or acrylic stain on your deck. A solid hide stain would completely blank out any discoloration remaining on the deck. However, the adhesion and penetration of the new stain is only as good as the adhesion of the remnants of stain you are going over. It is definitly better to remove all the old finish, either by sanding or chemical strippers.
A final word on mill glaze: before you ever stain a deck, whether new or old, you should test for mill glaze first. This is done by sprinkeling a little water on the bare wood. If the water does not almost immediately start to penetrate the wood, but merely bead on the surface, the new stain will also sit on the surface without penetration. You must open up the grain before staining!
Re: Deck Stain
What Ord said plus,
Do the sprinkle test in a few areas on your deck. High traffic areas will give different results than the spot on the deck that was under the lounge chair.
If you are in a rush, you can always sand your deck to open the pores. A really good power washing and scrubbing, followed by a nice long drying in the summer heat will help. By long I mean that may take a few weeks, depending on what y'all consider 'hot' and how much rain y'all get.
If your deck is trapping moisture from underneath, then the drying time will be greatly extended, if it ever dries out. Got good air flow?
Re: Deck Stain
the first thing you nees to do is use a stripper on the deck then p/wash it off i alway use a rotating blasting tip on the p/washer will remove almost anything let dry then you can use any type of sealer the best sealer i have found is called defy has an epoxy agent in it but you must follow the direction (that what happen to the cabot flaking)when you apply you must do a second coat with-in 20 min cabot's is also a great product when done right alway start with the railings make sure none get on the deck cause once dry it will show up darker when the deck is done then the flaking problem defy is waterbased can apply after you p/wash when dry good luck