The homeowner assumed they had three prices for one deck. They actually had prices for three different decks: different decking material, different footing depth, and only one bid that included the permit and engineered plans an elevated deck required.
Bid A: "5/4 PT decking." Bids B and C: "Composite decking, capped."
That single material choice accounts for a large share of the spread. Comparing them as if they're the same deck makes the cheapest bid look like a bargain instead of a different product.
What to ask: Please requote using capped composite so I'm comparing the same deck, and show the PT price as an alternate.
Bid C: "Includes permit and engineered plan." Bids A and B: silent.
An elevated deck with stairs almost always needs a permit and an inspection of footings before pour. A bid that omits it isn't cheaper — it's incomplete, and unpermitted structural work follows you to closing.
What to ask: Is the permit, the engineered plan, and the footing inspection included in your price? If not, what do you estimate they cost?
"Concrete footings" (A) vs "12" dia. footings to 24" below grade" (C).
Footing depth is set by frost line and local code, not preference. An unstated footing spec is the most common place an elevated deck bid gets thin.
What to ask: What diameter and depth are your footings, and does that meet the local frost-depth requirement?
"Attach ledger to house."
Ledger failure is the leading cause of deck collapse, and improper flashing rots the rim joist behind the siding where you'll never see it.
What to ask: What fasteners are you using at the ledger, and how is it flashed to keep water out of the rim joist?
"Railing to be code compliant."
"Code compliant" is the floor, not a product. Railing is often 15–20% of a deck's cost, so an unnamed railing makes the whole comparison unreliable.
What to ask: Which railing product and infill, and what's the price difference to the system in the other bid?
"Includes stairs, hangers, hardware, and haul-away."
The structural hardware and stair framing are consistent across bids, so the differences really are material, permit, and footing decisions.
What to ask: No action needed.
Thanks for the proposal. I'm comparing three bids and want them on the same scope. Could you confirm in writing: 1) a price using capped composite decking, with PT shown as an alternate, 2) whether the permit, engineered plan, and footing inspection are included, 3) your footing diameter and depth versus local frost depth, 4) the ledger fasteners and flashing detail, and 5) the specific railing product and infill?
What happened: Rebid on a written common scope, the spread closed to about $2,300 — and the original low bid was no longer the lowest.
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