On Dec 3, 8:20 am, DerbyDad03 wrote:
I was reading a Q&A on buildng a tall deck which contained the
following exchange.

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Q: My house has brick veneer over insulated stud walls. I am going to
build a raised deck off the second floor bedroom. It will be suported
by four posts, Should I attach the deck floor to the house wall?

A: It is probably better if you do not attach it securely to the house
wall. With tall wooden posts, the deck suface may move up and down
more than the house wall throughout the seasons.

To provide a more stable feel to the tall deck, screw steel angles to
the house wall. Screw another set of angles to the deck several
inches below the other ones. Connect them with long bolts to allow
some vertical movement.

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Can I assume that the bolts are to be left loose to allow for vertical
movement? How loose? Regarding the "stable feel" the author mentions
- would that be present because the loose bolts would supposedly
limit the horizontal movement somewhat?

Is this a common construction method for tall decks?

No, and the reasoning isn't logical. Wood moves seasonally due to
changes in moisture content, in width and depth, not length. The
other factor is wood's coefficient of thermal expansion - which is
totally negligible in the normal range of climactic conditions.

There's far greater risk of movement due to insufficient footing depth
and consequent frost heaving - and that can happen, in the same
amount, regardless of the post length.

R