Journal / DIY
Mount an equipment wall: plywood vs. cement board
Your inverter, disconnects and combiner need a flat, strong, and sometimes non-combustible surface. Here’s how to choose and install it.
The equipment wall is where your solar system becomes part of your house. A clean layout makes wiring easier, inspection faster, and service safer.
Choose the backer
| Painted plywood (3/4 in) | Cement board over studs | |
|---|---|---|
| Holds screws anywhere | Yes | No: fasten into studs or use anchors |
| Non-combustible | No | Yes |
| Best for | Disconnects, combiners, small boxes | Inverters that require it |
Many installers use both: cement board behind the inverter, painted plywood for everything else.
Lay it out before you drill
- Tape every box on the wall at full size.
- Mark the working space: 36 in deep, 30 in wide, 6.5 ft high in front of electrical equipment.
- Respect each manual’s clearances (the 12kPV wants 4.9 in to other components; Powerwall 3 wants 4 in on each side).
- Plan conduit paths so DC and AC enter from different sides and signal cables stay separate.
- Enter from the bottom or sides outdoors to keep water out.
Fasten it right
- Into studs with structural screws, or into masonry with sleeve anchors.
- Check the combined weight: an inverter can be 110 lb or more.
- Level the first bracket; everything else references it.
Quick answers
Does my inverter need a non-combustible wall?
Some do. The EG4 12kPV, for example, calls for a non-combustible surface. Check your inverter's manual.
Next step
See what your house needs.
Your usage chart and system size are free in the design app. The build-ready package is $149.
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