According to Code Check “Almost all balcony deck collapses are not the result of exceeding the allowable live load. Rather, they are from the failure of the attachment to the structure or from neglect and rot. All decks should be routinely inspected for deterioration, insect damage, fastener or connector corrosion & security of railings.”

Source Fine Home Building:
Never nail a joist to a post. This connection is poor and dangerous.

This article has some very economical upgrades for a deck that will make it much safer. Deck and stair issues kill and injure hundreds of people every year. Many of the repairs required are not expensive and make a huge safety.

I will start off with the post-to-beam attachments. This type of construction is dangerous, posts should bear weight under the beam, not attached to it. The single rim joist is not a beam and is way below safe building standards. We recommend this joist be doubled and provide proper bearing support on a post.

Building this way allows the posts to pass through the deck and be used for the guardrail.

This is fixed by doubling the rim joist and post using appropriate structural screws and post to beam hardware.
Rusting nails and low-grade hangers

The chemicals used in pressure treated lumber have changed over the years, and some will react with nails or joist hangers.

New hangers installed with approved screws

Hold-downs are installed, 2-1,500-lb. capacity through-bolted to floor joists & max 24 in. from each end of deck. This prevents the deck from separating from the house. Lag screws & bolts used to attach the rim must be hot-dipped galvanized or stainless steel.

Read the rest of this article and see how they fix the stairs, repair footings and repair the handrail here

Sources :
Code Check Building
Fine Home Building Magazine How to make an old deck-safe

JJ Greive

JJ & Suzanne are both licensed, highly skilled inspectors and educators. We are the authors of our class curriculum, and truly enjoy sharing this with our students