|I have a few 5-gallon cans of Behr Waterproof Deck Stain -- no. 300, clean
up with water, natural color -- that have been stored in a garage for
several years. Are they still usable? They've never been opened.
You can open the Behr cans and see if they can be
stirred OK. If so then they should be fine to use. It's
only when they gel that they're lost.
For what it's worth, some info about deck stains
might be useful. I build and stain decks regularly
and find the current market very frustrating. In the
switch from oil to water we just don't have good
products for most things. Though if you already
have an acrylic stain on your deck then you're
probably stuck with it, unless you replace the wood
or sand the deck.
I wouldn't touch anything Behr, simply because
it's Home Depot and quality is not their top priority.
To be honest, I've never actually tried anything but
a gallon of their wall paint, once.
Generally I'd avoid any paint HD carries. Even
reputable brands will likely be special blends for Home
Depot. It's not that HD is so bad. It's just that paint
quality can vary quite a bit, and most people can't
tell. So it's a good product for cutting costs on.
I think HD also carry Glidden, don't
they? I once did a job, many years ago, where the
customer insisted on Glidden solid oil exterior stain.
I tried to talk them out of it, but couldn't. I was going
to use Benjamin Moore, at $27/gallon. Glidden was $10.
So I saved a lot of money. (It was a 5-unit townhouse.)
But the Glidden had no body. Their own spec sheet
said it was 30% water. Water! In oil-base stain. They
were canning 2/3 stain with an emulsifier and 1/3 water.
It went on thick, then dissolved into a bubbly foam and
pretty much disappeared.
All of which is to say that there really are differences
in paint brands. With all the work involved it makes no
sense to save a few dollars on materials. But then if
you don't use the Behr you're faced with another
problem: There are no perfect options these days for
deck stain. Sherwin Williams is the best brand I'm
able to find, in general. Benjamin Moore is no longer
dependable. Pratt and Lmabert is best, but they were
bought out by Sherwin Williams. So if I had to use
acrylic deck stain I'd go for SW.
Solid oil stain is all but gone. I'm still using
Cabot solid oil stain on our deck, but it's become hard
to find. (15 years old. 4/4x6 PT. Still looks very good.
I came across some Cabot's solid oil in an old-fashioned
hardware store recently and grabbed another gallon. :)
Water-base deck stain is improving but it's really not
much better than wall paint. It shows dirt and scuff
marks, and wears away quickly. Urethane-reinforced
paint is another option -- acrylic or oil -- but that's a
nightmare down the road when you need to scrape
the peeling paint. It's very hard stuff.
Semi-transparent oil stain: Never looks all that good,
especially if you want a color other than dark wood-tone.
It's fine for cedar siding in a rustic setting, but not so
good for suburban/urban houses with painted siding.
Benj Moore now makes transparent stains that match
3 or 4 colors of Australian Timber Oil. That stuff is pretty
good. Oil-base. Nice colors. They say you can only do
one coat with it. That's not true. Two coats gives a
nice sheen and will cover things like grayed PT wood
pretty well. But one coat will work in most cases. The
down-side of that is that it's only good if you have bare
wood and want wood tone. As noted above, that's not
always a good match with the rest of the house.
Actual Australian Timber Oil has undergone a bait
and switch. It's no longer oil-base. The can seems to look
the same, but the product is water-base. Nothing like the
original product! Note, also, that Home Depot now sells it.
I figured that was a bad sign when I first came across it.
But I still wasted the price of one quart to find out it was
no longer anything remotely resembling the original product.
Maybe HD bought the ATO brand. I don't know.
I've used a mix in the past where I blend exterior oil-
base paint with boiled linseed oil and thinner. I've used
BM High Gloss Impervo for that, which is no longer
available. But other oil paint should work. The linseed
oil provides the durability. The paint supplies color and
driers. The thinner makes it soak in deeply. But nothing
provides the protection, durability, ease of use and
finished look of soild oil deck stain.
Some people may remember that not so long ago
virtually all decks and stairs were the same: 1x4 fir
treated with boiled linseed oil and thinner, just like
fir gutters. A recoat would be done occasionally. So
all steps and decks were gray after the first year or so.