sure void footer

[nuckjr]

I am currently having a new house built and have a question concerning the footer. The builder has just finished pouring the footer and is preparing to pour the foundation (basement) walls. I am very picky and question things I don't agree with. Anyhow, they have used a sure void with a lite skim coat of concrete for the footer. So I am wondering if it is possible that they poured another concrete footer beneath this that I am unable to see or is this it? I understand the reason for a form void but we are talking about 8" thick 9' tall foundation wall setting on this, not to mention the 2 stories of house above that. Can anyone give me some peace of mind?

 

[Focht3]

Where is the house? It sounds like you are in expansive clay/shale country if the builder is using concrete retaining blocks to maintain the void -

Does the house have drilled piers beneath the walls? If so, they are supporting the structural loads, and the walls are designed to span between the piers -

I am confused by your statement, they have used a sure void with a lite skim coat of concrete for the footer - please explain.



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[SteveBausch]

http://www.arcvoid.com/surevoid_web/index.html

 

[Focht3]

Thanks, Steve. [red]SureVoid[/red] is a brand of carton forms. Concrete retainer blocks may or may not have been used to make the voids "permanent." The lite skim coat of concrete for the footer is probably a concrete seal slab (also referred to as a mud slab) to protect the bottom of the excavation during construction.

[blue]nuckjr[/blue]:
Check with your builder to see if they constructed piers beneath the walls. Let us know what you find -



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[nuckjr]

I checked it out, and there is no piers. First off I live in Colorado and where the house is being built the soil is primarily sand. What they have done is use footer pads and sure void between the pads. This is something new to me. Where I am from you poured a solid footer with no voids. There are no concrete retaining blocks. If there was a way to send you pictures I would, that would probably explain it better. Thanks guys.

 

[Focht3]

That sounds like an odd way to build a house. Where is it? (City.) Has the builder told you why he's using void forms? (I would assume that he's addressing some expected problem.) How big are the footings? How deep to the bearing surface (bottom) of the footings? What have the building inspectors said?

As a side note - the design and construction of the house may be sound. But void forms beneath walls - in a sand environment - sounds peculiar.



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[enjuneer]

First thing you need to do is obtain a copy of the soils report and a copy of the engineered foundation plan. If you are along the front range both of these items should have been completed prior to construction.

The soils report most likely has given a footing recommendation with a maximum bearing capacity and a minimum dead load requirement, due to some moderately expansive clays in the soil.

Typically the void form is installed below the footing to allow the minimum dead load requirements to be met.