what came first, the pergola or the deck
i hope pro-dek doesn’t mind that i am reposting a couple of his pics from the thread
“wrong way ledger” http://forums.taunton.com/tp-breaktime/messages?msg=43134.1
to help illustrate my question. (if so, let me know and i will remove them)
we are in the planning stages of a 14′ x 25′ free standing redwood deck, 16″ above grade.
we plan on building a free standing pergola above the deck, but we are still up in the air about the design (2 posts, 4 posts, how wide, tall, etc..) what we do know is that it will be smaller than the deck.
my thoughts are to frame the deck, and then place the pergola posts on concrete piers where we want them. then finish laying the decking around the posts, notching/cutting where needed.
my father in law says we should build the pergola on top of the decking.
we are all aware of pro-dek’s quality work, and im glad to see that my thoughts are in line with how he built this pergola/deck in the pictures below.
so is there any reason why i would want to build the pergola on the decking? basically im looking for any ammunition to refute my father in law’s claim.
thanks all… and thanks pro-dek
Replies
basically im looking for any ammunition to refute my father in law's claim
Well, a pergola is a substantial structure. You would not just stand 4x4 or 6x4 up on the deck planking, it will require some sort of support from grade. Rather silly to build the deck, then pry up the lumber to put footings in for the pergola. (Just as silly if we are standing a 2x "patio cover" up, on the deckboards, hoping, as my ignorant neighbor is, on the benevolence of Nature never overwhelming gravity . . . )
Now, a person could debate whether to include the pergola columns in the deck design. The design, and the structural, arguments could go either way. Design-wise, building a "picture frame" around the pergola columns might be interesting, visually separating the deck from the pergola without relly losing any deck area. Is that worth the additional effort? Don't know--not my deck.
Oak,
The best ammunition is already in your hand...the very pictures you just posted!!
Pro-deck's pictures demonstrate a very sound method for building such a structure. The guy makes his living from building decks...if he builds them sloppy or inadequate, he's outa business...so he builds them right....you should "follow his lead."
Here's more ammo anyhow.....1)...as was earlier pointed out, you just can't place your posts on deck boards...the boards will at the very least, sag over time...at very worst, they will buckle under the point load. The post"s point load must be borne continuously straight down to a solid foundation .
2)...Setting your posts firmly in the ground below the deck would definately help keep your posts from "kicking out" or racking. Should posts run below deck level and be attached to concrete piers ( as you mention), such posts can, in addition to being attached to the concrete pier, can also be nailed or bolted to deck framework below; so as to more safely guard against racking.
Posts placed only on top of decking must rely solely on strength of a drift pin or a simpson post plate, plus gravity. This pin and/or post plate relies soley on strength of 5/4 deck board. But, attaching post bottoms underneath deck level allows you to install more than one connection point to hold posts firmly in place... while attaching above deck level only gives you one connection point . As you know, the more connections made, the stronger the joint.
3) Stronger almost always translates into longer....longer uninterrupted service. Sooo, ask your father-in law how many times over the course of the next several years does he mind returning and fixing your intended pergola.
LOL.
Davo
thanks for the input guys... i really appreciate it
oak