how to perform deck inspections course

How do you inspect a deck?

Inspect the wood Inspect several areas of your deck to ensure the wood is still sound. Specifically, check the ledger board, support posts and joists beneath the deck, deck floor boards, railings and stairs. Look for small hole in the wood or evidence of sawdust/wood dust.May 13, 2015

What do inspectors look for in a deck?

Inspectors will also be looking closely at the specific connections as they are assembled across the frame. They will want to see that you are using the proper joist hangers and they are not missing any fasteners. They will also be interested in seeing how well your beams are connected to your support posts.

What accounts for roughly 90% of all deck collapses?

About 90% of deck collapses occurred as a result of the separation of the deck ledger board from the house, allowing the deck to swing away from the house. It is very rare for deck floor joists to break mid-span. Many more injuries are the result of rail failure, rather than complete deck collapse.

What is a deck load carried by?

Building codes require decks to be designed to carry a uniformly distributed load over the entire deck. If evenly distributed, half of the load is carried by the deck-to-house connection, and the other half is carried by the posts. The image above depicts a typical deck load distribution.Jul 22, 2009

What causes decks to collapse?

Pulling Away From the House The most common mode of total deck collapse involves the deck “pulling away” from the house. This type of failure typically occurs because the ledger board was not properly attached to the house. There are many construction aspects that go into assuring the ledger board is properly attached.Jan 30, 2014

How do Decks fail?

Post and beam failures: Another leading cause of deck collapse is the failure of posts and beams, usually due to wood rot and undersized components. Posts set in soil, without protection, often rot to a point where they can no longer support loads. The same happens to beams that have not been properly maintained.

How do you inspect an Internachi exterior?

Many inspectors use binoculars to get a better look at components that are above their heads. When moving around the house, look up and inspect the eaves, soffits and fascia components. Inspectors should look at all of the exterior doors. While inspecting each exterior door, check each storm door (if present).

How often do decks collapse?

In fact, over 500 people are injured in deck collapses every year, and for some it is even fatal. In a recent interview with Today show's Jeff Rosen, structural engineer Scott Fischer said that of the 40 million decks in the U.S., about half of them are not built to code.Apr 11, 2018

Can balusters be used in place of posts?

T/F: Balusters can be used in place of posts if there is adequate infill between them. T/F: End-grains of vertical posts and balusters should be cut level. Deck planking segments should bear on a minimum of _____ joists. T/F: Deck planking should be laid together as tightly as possible.

How do you calculate deck loads?

To determine the maximum load capacity of your deck, start by calculating its total area and multiply by 50 psf. So, a 100 sqft deck would be designed to support 5000 lbs. Do not get confused with what weight you might think or want to load the deck with.

What is a typical live load for a deck?

For a residential deck, the code requires it be designed to support a minimum 40-psf live load. The live load is the external force applied to a deck due to the activities of its use. People, furniture and any other movable, physical objects on the deck are covered under live load.

How many joists do I need for a 20 foot deck?

A 20-foot wide deck, for example, would require two beams: one at 10 feet and one and 20 feet in order to support a deck with 2×8 joists spaced 16 inches apart.

Where should an inspector start on a deck?

Inspectors should start at the bottom. If a deck is deemed unsafe from underneath, the inspector should not walk out onto the deck to inspect the decking, handrails, etc. The inspector should stop and report the safety issues. The image above depicts an evenly distributed deck load.

What is a deck in a house?

A deck is a large, raised wooden floor attached to the back of a house, and contained by a perimeter railing for safety . Decks are rarely covered, and usually have a rough or informal look that is not integrated with the rest of the house's design.

Why do decks collapse?

About 90% of deck collapses occurred as a result of the separation of the deck ledger board from the house, allowing the deck to swing away from the house. It is very rare for deck floor joists to break mid-span. Many more injuries are the result of rail failure, rather than complete deck collapse.

How many decks are built in the US each year?

More than 2 million decks are built and replaced each year in North America. InterNACHI estimates that of the 45 million existing decks, only 40% are completely safe. Because decks appear to be simple to build, many people do not realize that decks are, in fact, structures that need to be designed to adequately resist certain stresses.

How high should a guardrail be on a deck?

Some codes require guardrails only around the edges of decks 30 inches or higher. Improper Guardrail Height. Most residential codes require the top of the guardrail to be at least 36 inches from the deck surface.

How deep is a notch?

On the tension and compression faces, the notch depth must be less than one-sixth of the member's depth, and the notch length must be less than one-third of the member's depth. Notches are not permitted in the middle third of spans, or on the tension face of members that are greater than 3½ inches thick.

How many feet should a footing be?

On steep properties, the slope of the ground around the footing could affect the footing's stability. The 7-Foot Rule states that there should be a least 7 feet between the bottom of a footing and daylight. Posts in contact with soil should be pressure-treated and oriented so the cut end is above grade.

Goal

This course teaches the inspector to perform residential and commercial wood deck inspections. It includes a review of all common deck defects.

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