Need a book? Engineering books recommendations...

# Re: Soccer Field on a Roof

• To: seaint-seaosc(--nospam--at)mail-list.com
• Subject: Re: Soccer Field on a Roof
• From: Davis Parsons <davisp2(--nospam--at)att.net>
• Date: Fri, 22 Aug 2014 15:43:59 -0500
• List-subscribe: <mailto:SEAINT-SEAOSC-on@mail-list.com>

Geofoam. It is used as a fill under concrete slabs in this area all the time. I have a stair project right now where geofoam is used to raise a raise floor area. Original slab difference is 5'-0". 4'-6" of geofoam is used with a 6" concrete slab to level the new and old floor levels.
```
*Davis G. Parsons II PE RA *
/Texas Engineer 42397//
Texas Architect  9462/
Fort Worth, Texas
817.366.0976

On 8/22/2014 3:33 PM, T. William (Bill) Allen, S.E. wrote:
```
```Now that I know who is awake and working on Friday....
:o)

```
I have a project where the owner wants to put a soccer field on a roof. Don't laugh. Yes, the soccer field must be flat (or mostly so, slope of 1" in 10 feet to get the water to drain off of the 2 foot square tiles. The roof below will slope at a much more significant slope. Architect wants minimum which is ¼" per foot. I want ½" per foot. We may compromise at 3/8" per foot.
```
```
The question is, what can we use to fill up the space? The first thing that comes to mind is sand, but that will be very heavy. If the roof slopes ½" per foot, the average weight will be 135 PSF (assuming wet sand at 120 PCF). At 3/8" per foot, the average weight will be 100 PSF. The difference is nearly 200k lbs for the project!
```
```
The architect asked me about vermiculite. I have NO IDEA if vermiculite is stiff enough. My (considerable) gut says "no".
```
Any ideas?
```
```
-------------------------------------------------------------------------
```
Post your message to the list by sending it to: SEAINT-SEAOSC(--nospam--at)mail-list.com.
```
The email messages sent to the list will be saved in an archive on the World Wide Web.
These archives are located at:
http://archive.mail-list.com/SEAINT-SEAOSC

To contact the list owner, send your message to:
SEAINT-SEAOSC-list-owner(--nospam--at)mail-list.com.

Sponsored By: Pacific Structural & Forensic Engineers Group, Inc. (PSFEG)