free standing FDC drainage with no basement

[acb324]

I try to avoid at all costs a free standing fire department connection whenever there is no basement in a building due to drainage concerns. I have heard horror stories of the trapped FDC pipe having remaining water from testing or poor drainage, then freezing and leaking or corroding. Despite inspection and testing requirements, this condition is often not discovered until it is too late (during an emergency).

Unfortunately, I have found myself in a situation in which the architect will not accommodate a flush mounted FDC and there is no basement. The check valve will be located inside the building, so there will be no vault or access to this buried piping. I obviously specify to follow all NFPA 13 rules for underground piping, but my question is this: What do you typically specify to ensure drainage of the underground trapped "U" of piping between the FDC and the check valve?

 

[PEDARRIN2]

Done it all the time.

Install a small 3' dia pre cast manhole with an open bottom close to the FDC. Line with gravel. Bury piping below freeze line and extend pipe upstream of the FDC sloped slightly toward the manhole and provide a ball drip.

Put a lid on the manhole for access and inspection of ball drip.

 

[acb324]

Thank you for your reply, I too envisioned some kind of gravel pit, but I am concerned about lack of access and the "bury it and forget it" attitude.

Is there anything governing this type of installation? Maybe 13.2.3 of NFPA 25? All system valves shall be protected from physical damage and shall be accessible? The AHJ has requested 3 FDCs and I would like something to point to in order to require this access since I am receiving resistance from the architect on so many things due to cost or affecting the aesthetics.

 

[PEDARRIN2]

I don't know if access is required in this case, but it is value added.

Given there is no basement to extend the piping to, the pipe has to drain somehow or it will freeze.

If the architect is worried about aesthetics, tell him/her to put some shrubs in the area, just not in front of the FDC.

Tell the architect you can make it pretty (which will be inexpensive and pretty now but very expensive later) or you can make it functional (which will be marginally more expensive now, but he will not have to explain to the owner why his facility burnt down because the FDC piping was not functional because it had frozen in the past which is why the fire department was delayed in putting out the fire because they couldn't hook up their equipment to the building fire suppression system).

Document the decision so you have it in the project file so if something happens, you have a record about what you recommended and that it was not followed.

When a lawsuit happens, that piece of paper will be very important.