deck maintanence

[mickfromperth]

Hi,

I've seen quite a few posts talking about deck maintanence when people have asked questions about building low clearance decks.

What exactly are maintanence type issues one should think about and plan for when building a deck?

Here is a list of some I can infer from other peoples posts:
1) Ability to clean underneath. Eventiually it's going to fill up with sand or dirt and you should be able to rake or wash this away. Right? Do people actually do this?
2) Termite check. How much clearance is required? For this activity? What if I put my deck at ground level?
3) Drainage. Is the soil under the deck is the lowest point around, thats where water will collect. I guess I'm lucky here. WA is a sandpit. I din't expect this to be to much of a problem although I'm going to have planty of soakwells soon.
4) I guess finish? What refinishing is required based on your chosen finish?
5) And thats about it for me.. Got more? Post em!

Mike

[strangerep]

[...] low clearance decks. [...]

1) Ability to clean underneath. Eventually it's going to fill up with
sand or dirt and you should be able to rake or wash this away. Right? Do
people actually do this?
I had an experience where the previous owners had a deck extension
installed, and either didn't check, or didn't bother. After quite
a few years the tiny amount of leaves, etc, that gradually get through
the cracks built up. So bearers & joists that were designed only for
out-of-ground well-drained application had to cope with an in-ground
environment. I've spent a lot of time in the past year reconstructing
the entire thing. (sigh)

What I'm saying is: it will take many years before you realize you should
have constructed the deck in a different way, or should have checked
more often. I suspect most people don't check, and they eventually pay
the price.

If there is any possibility that dirt will build up over the years
and touch your bearers/joists, then choose either H4 treated pine, or
in-ground class-1 durability hardwood. Even then, I would give them a
coat of stop-rot, and maybe even creosote for the most at-risk surfaces
(if creosote is still legal in your state). I used tallowwood with
stop-rot and creosote as described, including along the tops and in
the bolt holes, plus alcor flashing on top. All bearers and joists were
thoroughly painted all around before being installed.



2) Termite check. How much clearance is required? For this activity?
What if I put my deck at ground level?
Use termite-resistant timbers and preservatives in the first place,
as described above. Don't rely on initial clearance being maintained
over the years.



3) Drainage. [...] One aspect of drainage that many people don't consider is the surface
between joist and decking, i.e: on top of the joist. One naively thinks
that the water will just drain away easily. However, between joist and
decking, the timber can stay wet after rain for many days, depending
on local conditions. It's quite surprising to lift up a board on an
apparently bone-dry deck and find dampness. This means that the surface
between joist and deck is better imagined as an in-ground situation: damp
for long periods of time. This can be mitigated with alcor flashing over
the joists (though take care to get the fall right), but it's still wise
to choose class-1 species for both joists and decking. The whole thing
will last much longer.



4) What refinishing is required based on your chosen finish?
There's basically 2 choices: decking oil (e.g: Feast-Watson, Cabots) or
acryllic-based (e.g: Intergrain DWD, "Spa-n-Deck"). Oh, and there's also
some stuff from Sikens (sic?) that I haven't researched properly yet.

Acryllics are claimed to last considerably longer, but tend to be shinier
than decking oil, and trickier to re-apply. In contrast, re-application of
decking oil just needs the deck to be clean.

Depending on the orientation of your deck relative to the sun and where
you normally view it from, the shine of acryllics a may or may not be
a problem. My deck has full north aspect, so after experimenting with
both options I went for decking oil, even though there's a lot more
maintenance involved, especially in the first year or two if you want
to keep it looking nice. Washing the decking thoroughly initially is
unbelievably important, but very hard to achieve adequately. (Most
books/people don't emphasize this aspect enough, imho.) If you don't
remove all the tannins and soluble salts, it will look awful quite
quickly. I washed it obsessively, and pre-oiled all sides before
fastening.


Other aspects for possible discussion:

5) Choice of fasteners, and nail/screw practice.
6) Choice of decking timber to have acceptable surface splitting.

I can say some stuff about these in a subsequent post if you're
interested, though perhaps you were primarily focussed on the
low-clearance issues. Right now I have to go re-oil my deck. ;)