CALGreen Section: 5.303.2.1 Multiple showerheads serving one shower. When a shower is served by more than one showerhead, the combined flow rate of all the showerheads controlled by a single valve shall not exceed the maximum flow rate at ≥20 percent reduction contained in Table 5.303.2.2 or the shower shall be designed to only allow one showerhead to be in operation at a time.
Exception: The maximum flow rate for shower heads when using the performance method specified in Section 5.303.2.1, Item 2 is 2.5 gpm @ 80 psi.
Intent:
The intent of this code provision is to establish that the maximum flow rate in the 20 percent reduction table covers all applications where water sprays from multiple sources at one time.
It is not the intent to permit multiple independent water supply lines to a single shower
enclosure. This is intended to cover a single shower enclosure or space. In multiple shower spaces or gang showers, the requirement shall apply to each shower.
Change for 2012: CBSC is proposing the modification of these sections and tables in response to comments from CARB and to coordinate language with HCD. The primary modification is to indicate that only those showerheads controlled by a single valve must comply. Though it is stated above that it is not the intent to encourage multiple supply lines, they are not prohibited by this section.
Existing Law or Regulation:
There is NO current law or regulation for this code provision.
Compliance Method:
Specify the shower fixture and fittings to either:
1. Restrict the flow at the valve that serves all the showerheads to provide no more than 2 gpm @ 80 psi as specified in the 20 percent reduction column contained in Table 5.303.2.3;
2. Specify a valve that is designed to allow only one showerhead to be in operation at a time with a maximum flow rate of 2 gpm @ 80 psi; or
3. Performance Method: Refer to Table 5.303.2.2 and provide a calculation demonstrating a
20 percent reduction in the building “water use baseline” with a maximum combined flow rate of 2.5 gpm@80 psi for multiple showerheads.
Contractor: Contractor should be able to provide documentation or self-certification form to the inspector.
Suggestion: Provide a note on the plans that multiple shower heads controlled by a single valve shall have a combined flow rate of all the showerheads not to exceed the maximum flow rates specified in the 20 percent reduction column contained in Table 5.303.2.3. Or note that shower heads are being controlled to work independently. When using the Exception, provide a plumbing calculation on the plans.
Sample worksheets are included in Chapter 8 of the code and Part 4 of this Guide.
Enforcement:
Plan Intake: The reviewer and/or plan checker should review the plans and confirm that multiple shower heads specified meet the combined flow rates on the tables or that they are
plumbed to operate independently or that the performance method does not exceed the combined maximum flow rates.
On-Site Enforcement: The inspector should review the permit set of plans to verify that the specified showerheads and/or water reducing fittings are installed. If the performance method was used, the inspector will confirm that showerheads or systems used to reduce overall water use by 20 percent have been installed. The inspector may review fixture specifications provided by the manufacturers as verification of compliance. Testing of flow rates may be done at the inspector’s discretion.
Sorry, the comment form is closed at this time.