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Deck Dangers: What To Avoid When Building Your Deck

Deck Dangers: What To Avoid When Building A Deck

How To Build A Deck

While many opt to build their own deck, we want to advise you to be very careful about your construction. With that in mind, let’s go over some things to avoid when building your own deck!

Side Note: Huge thank you to our inspector, Wilmer Mollfulleda, for supplying the photos in this blog!

What To Avoid

Fasteners

You should always ensure the fasteners you are using are rated for the job/load you are building. To illustrate, generic wood screws would not be sufficient, rather, you would want anti-corrosive fasteners at the proper length.

Family Handy Man goes into more depth about the different types of deck fasteners.

Also, every joist hanger should have the maximum number of screws allotted. Therefore, there should NOT be any missing fasteners at any joist hangers.

Joist Sizing

As a rule of thumb, joists should be larger than what they are supporting. Therefore a 2 x 6 should not be supporting a 2 x 8 as seen in the image below.

Improper Joist Sizing

For more appropriate sizing, recommend viewing the joist sizing chart from decks.com.

Wood Touching The Ground

This is a fairly common mistake, especially in southern climates. Only pressure treated wood should be in contact with the ground. Also, concrete footings are needed to ensure stability.

Deck Boards, Balusters, and Railings

Deck boards should be closely packed together so heels and children’s feet do not fall through.

Balusters on the other hand, should no more than 4inches apart to prevent small children from falling through.

Lastly, railings should not have horizontal boards to allow for climbing and railings should be continuous all the way up. Continuous means, your hand should not have to be lifted in order to continue holding onto the railing.

Attaching Your Deck To The Home – Preventing Decay & Failure

If you are planning to attach your deck to the home rather than having a free-standing deck, you should install proper flashing.

Flashing should be installed under the siding of the home, and then come out to go over the deck ledger. This will prevent rain from making it through the siding and stop wood decay. Read more about attaching your ledger board.

deck ledger board
In the image above, this deck is attached to the home. However, we can clearly see daylight coming through the ledger board. This means water can enter between the ledger board and the home. Also, the ledger board might be pulling away from the home meaning the board is not properly attached.

Notching Joists

Notching joists are often completed improperly. Here are some rules when adding notches to your deck.

  • The maximum depth of a notch at the end of a joist (where it rests on a wall or beam) can’t exceed one-quarter of the joist depth.
  • Maximum notch depth in the outer third of a joist is one-sixth of the joist depth.
  • Limit the length of notches to one-third of the joist depth.
  • No notching in the middle third of a joist.

For more detailed rules, check out rules for notching.

Deck Inspections

In most areas, city/county inspections are required for permitting of your deck. However, many homeowners are unaware the inspections have little influence on the building of the deck. In most cases, the local official will just want to ensure there are engineered drawings (especially in climates like Florida).

This leaves inspections often up to the home inspector once a home is being sold. Home inspectors often write decks in their reports for needing evaluation and repairs by a licensed professional since most decks are not built professionally.

Home Inspectors will look for many items, but here is a short list:

  • Wood decay/rotting
  • Loose railings
  • Proper fasteners
  • Proper joist sizing
  • Hardware corrosion
  • Footings
  • Attachment to the home
  • Post condition

Summing Up Building Your Own Deck Dangers

Final Tips From Inspector Steve Helm.

Never build your deck with plain construction materials. Either use pressure treated wood or composite. This will ensure longevity for the deck due to who damage and moisture. When placing the deck floor always keep the boards tight together when using pressure treated. The boards are wet when purchased. Allow for shrinking. Use fasteners suitable for the material being used. Pressure treated wood has an acidic content and will eat though some fasteners. Always check with local building codes and planners. You do not want to build were you are not supposed to.

Inspector Steve Helm

If you are planning to build a deck on your own, it is important to do the proper research and planning.

Decks can easily fall and cause injuries so ensuring your deck is built to code and properly permitting will help keep others safe.

If you have questions about your deck, comment below! For more on decks, we have a blog post on docks and seawalls.