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marvin
hollow open concrete porch help

Home was built in the early 70s, ranch style, brick exterior.w/ covered front porch. The front porch is poured concrete in metel pans with broken red tile as finish.My guess is concrete is 2 inchs thick, Porch sits about 3.5 to 4 feet off the ground. Vents on both ends. Home is dry under home.The porch is hollow. porch size is 5x 25, there is not piers or supports in place other than the ledge from when it was origionally poured. The other day I went under house and went under porch area.I noticed the metel pans that was used to form the concrete is now rusting thru, some are completly gone.Most are in bad condition. I can see some exposed concrete as well. I need advice. Is this normal, is it safe. More important what should I do. I am sure contractors here will want a job and tell me the worst. Please advise.

canuk
Re: hollow open concrete porch help

Marvin,
as mentioned in the private message here are some comments.

The metal you described is known as deck pan. Instead of using wood, a metal form used in pouring concrete on horizontal planes such as roofs , porches ( like yours ) etc. ---- in other words -- where there is nothing underneath to hold the concrete in place while being poured.

This deck pan stays in place once the concrete is poured and cured. Unfortunately this material does rust out , as in your case. In the use for the porch that deck pan is not likely being used for any structural reinforcement.
Your concrete should have at least 10 or 6 inch wire mesh or rebar ( which is more likely ) along with 4 " ( minimum ) or thicker concrete pad.
Based on the the width of 5 feet and the intended use it's likely fine.

If you are in doubt there's nothing wrong with contacting a structural engineer to evaluate the concrete porch. For around $300 - $500 the engineer will give you peace of mind.

Cheers.:)

marvin
Re: hollow open concrete porch help

Do you suggest any local engineer in this area who specializes in this field, How would I know there is wire mesh or rebar in concrete? My guess is the concrete is 2.5 to 3 in thick?Please advise.

canuk
Re: hollow open concrete porch help

Contacting a local structural engineer would be a good choice since they would be familiar with local codes and building techniques.

You wouldn't be able to tell what re-enforcing material was used by surface appearance--- experience or exploration would determine this.

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