Water Pressure Calculation

[fayazdin]

Hello everyone.
I know this is HVAC Portal, but many of the consulting engineers design HVAC and Plumbing both.
I hope, I find someone from Las Vegas, who will understand the pain.
City of Las Vegas ask for water calculation on almost every project. I can understand on a new project that we can do water pressure calculations. How about tenant improvements? where no one knows how the building pressure calcluation were performed, no drawings, no data.
As I understand, as a Plumbing / Mechanical engineer, our responsibility is up to 5-feet from the building, but in Las Vegas, meteres are installed 100s of feet from the building and that becomes the responsibility of a civil engineer.
Has anyone came across this issue and how you resolve it?
Do we have to analyze the whole building to find pressure at the tenant's space? City of Las Vegas made me analyze the entire block (fixture units) in order for me to provide pressure at my tenant's space

 

[smo12345]

Why did they make you analyze the entire block. There is probably 1 meter serving your building. I could see an analysis of the building, but one meter doesn't serve the entire block.

I would call CLV to get the pressure at the intersections on both sides of the site location. This will give you an idea of the pressure at your meter. If you don't have any drawing you'll have to do some investigation/estimation regarding the routing and size of pipe from the meter to your location. Do an Appendix A calc and show an allocation of fixtures to the other tenants served by the main. You'll have to estimate this based on tenant use (i.e. restaurant or retail). Size your pipes according to Appendix A and show this calc on your drawings. This has worked for me in CLV when doing remodels on existing buildings with no drawings.

If CLV is requiring exact pressure have the owner get a plumber out there to perform a pressure test for your tenant space. However, if this is a shell building and you are the 1st T.I. this pressure will definitely change as others build out.