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Architectural Drawings for Solar Thermal Systems

Scope

Plumbing riser detail
Plumbing riser detail

Provide an architectural drawing and riser diagram for the homeowner showing the planned location for future solar hot water and photovoltaic system components. Space requirements and layout for solar water heating and photovoltaic system components should be taken into account early in the design process. 

See the Compliance Tab for links to related codes and standards and voluntary federal energy-efficiency program requirements.

Description

A renewable energy-ready home (RERH) is one that is built with the wiring and plumbing conduit and other components in place to facilitate the future installation of solar photovoltaic panels and/or solar water heating panels. Some energy-efficiency programs, like the U.S. Department of Energy’s DOE Zero Energy Ready Home Program, require homes to be renewable-energy ready.

When constructing a home to be renewable energy ready, develop architectural drawings and plumbing riser diagrams that summarize the installed system equipment (pipe chase, etc.). The drawings should accurately represent the installed elements of the system during the final inspection of the house; these drawings should be included in the homeowner education packet.

To meet the requirements of the DOE Zero Energy Ready Home program, the builder should provide a basic architectural drawing to the homeowner summarizing where the equipment is located within the house (see Figure 1). The builder should also provide the homeowner with a plumbing riser detail of the solar water heating system components. This diagram should have sufficient detail to clearly identify:

  • Pipe chase size and type
  • Length of chase from the designated roof/attic termination point to the utility room
  • Designated location and allotted space size of future hot water tank
  • Designated location and allotted space size of pump package mounting panel.

How to Create an Architectural Drawing for Solar Hot Water:

  1. Create a plumbing riser diagram like the one shown in Figure 1 that includes all of the following components of the solar hot water system:
    • Proposed location and square footage for the solar hot water panel array on the roof (preferably directly above the utility room)
    • Pipe chase from attic to utility room with size, type, and location clearly indicated.
    • Utility room space that contains
      • 3’ x 3’ x 7’ extra space for a solar hot water heater
      • a 3’ x 2’ plywood panel mounted on the wall adjacent to the solar hot water tank location for balance of system components
      • a solar bypass valve on the cold inlet to the existing water heater
      • access to the plumbing and wiring chase that extends to the proposed solar thermal panel array on the roof. 
Provide the home owner with an architectural drawing showing the location of existing and future solar water heating system components.
Figure 1. Provide the home owner with an architectural drawing showing the location of existing and future solar water heating system components (Source: Courtesy of EPA). 

 

Ensuring Success

Ensure adequate utility room size and location for solar water heating and photovoltaic system components early in the house design process. 

Confirm with local code officials early in the design process what steps are needed to guarantee that installation of solar water heating panels will meet with local codes, homeowner's association covenants, and historic district regulations. See the article on building codes and regulations related to solar water heating systems at Energy.gov for additional information.

Region

The DOE Zero Energy Ready Home PV-Ready Checklist (Revision 07)  is required only under the following condition related to climate (See the Compliance Tab  for other exceptions):

  • Location, based on zip code, has at least 5 kWh/m2/day average daily solar radiation based on annual solar insolation using the PVWatts online tool. See map below. 

In climates where freezing temperatures are likely to occur, a closed-loop anti-freeze system with a heat exchanger will keep outdoor water pipes from freezing and bursting.

Map of average daily solar radiation.
Figure 1. Map of average daily solar radiation per month (Source: Best Practices Series, Volume 6, High Performance Home Technologies: Solar Thermal and Photovoltaic Systems 2007). 

 

Training

Presentations

Compliance

DOE Zero Energy Ready Home

International Energy Conservation Code (IECC)

International Residential Code (IRC)

International Mechanical Code (IMC)

More Info

Case Studies

References and Resources

Solar Water Heating - Specification, Checklist and Guide

Publication Date
·
Author(s)
U.S. Environmental Protection Agency
·
Organization(s)
EPA
Description
Specifications to assist builders in designing and constructing homes equipped with a set of features that make the installation of solar energy systems after the completion of the home’s construction easier and less expensive.

For Homes

Publication Date
·
Author(s)
Florida Solar Energy Center
·
Organization(s)
FSEC
Description
Website with information for consumers about solar thermal systems for homes.

General Solar Thermal Specification

Publication Date
·
Author(s)
Aldrich Robb
·
Organization(s)
Consortium for Advanced Residential Buildings,
CARB,
Steven Winter Associates,
SWA
Description
Brochure on specifications for solar thermal systems.

*For non-dated media, such as websites, the date listed is the date accessed.

Contributors to this Guide

The following authors and organizations contributed to the content in this Guide.

Pacific Northwest National Laboratory 

Sales

Building Science-to-Sales Translator

Solar DHW Ready Home

Image(s)

Technical Description

Solar hot water systems use energy from the sun to heat water for use in the home. The easiest time to prepare a home for the installation of these systems is during design and construction. A solar hot water-ready home does this by providing plumbing lines from the attic to the hot water heater, chases for wiring, documentation that the roof is designed to support the extra weight of the solar thermal panels, adequate roof space for the solar collector array that is not shaded, and adequate space in the utility room for an additional solar hot water tank, pumps, and controls. 

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Disclaimer

This content is a work created with funding provided by the United States Department of Energy under Contract no DE-AC05-076RL01830 for the operation of Pacific Northwest National Laboratory. The information and guidance provided by Pacific Northwest National Laboratory (PNNL) in the content are intended solely for educational purposes only and do not constitute formal training or certification. It is provided with the explicit understanding that neither the United States Government nor the United States Department of Energy, nor the Contractor, nor any or their employees, nor any jurisdiction or organization that has cooperated in the development of these materials, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness or any information, apparatus, product, software, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or Battelle Memorial Institute. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Viewers assumes full responsibility for all actions that they may take from information provided in this content including ensuring the safety, code compliance, and proper functionality of any products they choose to install. Installation and use of such products should be performed in accordance with local regulations and manufacturer instructions.