Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Name of this roof slab supporting fabric with wire mesh? 1

Status
Not open for further replies.

RPGs

Structural
Oct 20, 2022
147
Greetings Eng Tips folks, I hope you're doing well.

I am working on a building with a concrete roof poured over some sort of plastic fabric with steel wire woven into it (picture attached).

I was wondering if anyone can recognize the fabric with wire mesh and let me know what it's called. I am having some trouble finding it on Google by just typing in a description of it.

I really appreciate the help, thank you.
 
 https://files.engineering.com/getfile.aspx?folder=f42230ad-2247-44e4-a59f-e54fa99d1dc3&file=photo_2@05-04-2024_17-13-43.jpg
Replies continue below

Recommended for you

photo_2_05-04-2024_17-13-43_onwbhz.jpg
yyy

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
LittleInch, you the real MVP.

Where is this building and what year was it built?
 
Pottstown, PA. I believe 1950's. No original plans available.
 
That's 70 years old?

Were trusses like that around then?

How can that be the original base material? Looks like the underside of a mattress to me.
Think we'll need a few more photos or data?
And why do you want to know?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Took me a while to find the project, but these bar joists have an identical assembly to some I saw in a building that was built in 1963, so potentially ~60 years old.

I've never seen anything like it before. I can only guess if it's original or not, but it seems like didn't work very well for forming the roof slab; the roof slab bulges visibly downwards between bar joists where the fabric sagged during concrete placement. The sagging slab/fabric is worse (1-2") at the perimeter framing.

The roof above has no consistent slope (???) and two drains that don't really work since there's no real slope to them. I observed ponding 2-3" deep across the entire roof when I was there (pic below), but there is not any significant leaking, which was quite surprising.

Unfortunately I don't really have any better photos of the underside of the roof right now or more data. I am waiting on more demo to be completed and test holes to determine roof slab thickness and see if any reinforcement is present.

The client wants to add a 2nd story to this existing roof. I was hoping someone might recognize the fabric as something that was used back then, so I could at least call it the right name and hopefully do some reading on it/find some details. I don't have a good feeling about it though.

photo_8_05-04-2024_17-13-43_chv74v.jpg
 
Looks like it's called fabric formwork or flexible formwork.

See attached

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Thank you, LittleInch! I greatly appreciate your help.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor