# Gravel under slab?



## kc2651 (Dec 12, 2007)

i have a house built in 1968 with a full basement i am remodeling. i have a small level of radon i would like to bust up the concrete and install a 4" pipe then exhaust up and out. So here is my question does anyone know if there might be a gravel bed under the slab built in 1968?


----------



## mudmixer (Dec 12, 2007)

There should have been, but you will never know until you get there.

Rock will be necessary to collect radon gas.


----------



## radonguy (Dec 13, 2007)

You do not have to remove your floor to make a radon mitigation system work. 

We routinely fix homes where no gravel or even sand was used as a final grade. The key to getting the system to work is to measure the potential for air movement under the slab and then the number of suction points and fan size can be determined. 

If want help let me know.


----------



## kc2651 (Dec 13, 2007)

ok sounds good to me Radon Guy you have my attention i would love to have your help with any and all in sight. just to recap 1400 sqaure feet finished basement with a block structure surrounding the basement and two walls being the front and one side underground the other two have brick outside of the block. thanks


----------



## radonguy (Dec 13, 2007)

What's your radon level?


----------



## kc2651 (Dec 13, 2007)

it is around 5 if memory serves me right. i want to add a side note in two of my rooms i have laid a vct tile floor which required some floor leveling with this added mortar and tile does that help block radon from entering?


----------



## radonguy (Dec 13, 2007)

It would have helped if there were some large cracks that you sealed. But most of the radon likely enters up through your block walls.


----------

