Mounting solar panels

Fixed mounting of solar panels is a consideration as reorienting them even only a couple of times a year can get tedious, dangerous or impossible. Tedious because few are the humans who relish periodic maintenance tasks, dangerous in that panels are often located on rooftops, and impossible when the owner is aged and physical health prohibits him from climbing ladders, teetering on rooftops, etc.

For fixed-angle mounting, please peruse Fixed tilt

ProSolar mounting system

This system is under study. It costs money, but is not exorbitant. This research does not constitute an endorsement.

The ProSolar system consists of stand-offs into roof with flashing, rails mounted to stand-offs, and clamps mounted to rails to hold panels. Below is an illustration of clamps. Figure 1 are "end" clamps that grip the edge of one panel while Figure 2 are clamps that grip two edges, i.e.: middle or "in-between" clamps. Below the clamp is a sort of wedge that slides along inside the rail. Tightening its nut head will anchor the clamp in the rail channel.

Approximate prices for ProSolar parts in this system are:

Rail 1½" × 136" (11-⅓') $26 Shorter, cheaper, but requires 4' on center stand-off mounting
Rail 2½" × 136" (11-⅓') $34 6' on center mounting; choosing this rail—allows for using fewer stand-offs!
Stand-offs 4½" $8.29 Bottom rail
Stand-offs 7½" $12.29 Taller stand-off to jack top rail up a bit
Flashing collar $6.34 For each stand-off
End clamps (various sizes) $3 Must determine size needed
Middle clamps (various sizes) $3 Must determine size needed
Channel nuts $0.51 Need one per clamp used

Illustrations of the ProSolar components

Rail, will need 2, mounted at 6 points
on stand-offs

Stand-off, 4½,
will need 3;
lag-screw into rafter

Stand-off, 7½,
will need 3;
lag-screw into rafter

Flashing for stand-off,
will need 6; tuck under
shingle above, overlap
shingle below

End clamp,
mount panel flat
against rail or
can be used for
multiple purposes

Middle clamp, if
panels to be mounted
flat against rail.
If 7 panels to be
mounted on 12' rail,
middle clamps must be

Channel nut, one
per clamp requred.
These take up room
in the channel!


How to install stand-offs with flashing. This is why I bought this system: it's perfect and won't compromise shingled-roof integrity. Click "FastJack™ Installation."


The "material support platform" below is a simple table 24" long with a 14" leg made to sit on a (7/12) roof to offer a horizontal surface on which to set tools and supplies waiting to be used. Could use a sheet of inexpensive ⅝ OSB.

Gather needed tools

▢ Air ratchet with sockets sized to lag- and other screwheads (and hose)
▢ Ratchet extension
▢ Ratchet
▢ DeWalt drill and bits (one for piloting lag screws, another for piloting sheet metal screws)
▢ Chalk line
▢ Crayon (to mark shingles)
▢ Tape measure
▢ Levels

Gather needed supplies

▢ Material support platform
▢ Stand-offs
▢ Flashing collars
▢ Tar and sealant
▢ Clamps and channel nuts
▢ Rails
▢ Solar panels

Prepare aids

▢ Build material support platform (14" leg x 24" table)
▢ Preposition platform, tools and materials to roof


  1. Install safety harness anchor
  2. Draw chalk line to ensure stand-offs are in-line, upper and bottom sets
  3. Install 4 stand-offs at marked points (see video here)
    1. Peel back shingle
    2. Paint with tar sealant (not on video)
    3. Drill pilot hole
    4. Goop pilot hole with other caulking sealant (not on video)
    5. Lag down stand-off base
    6. Install flashing (under shingles)
    7. Install rest of stand-off
    8. Goop and install flashing collar
  4. Measure positions for and install remaining 2 stand-offs
  5. Install rails
    1. Measure and drill out east-most holes
    2. Attach to east-most stand-offs
    3. Swing rail across remaining middle and west-most stand-offs
    4. Measure and drill out holes
    5. Attach rail to middle and west-most stand-offs
  6. Slide in rail channel nuts, do not tighten
  7. Add clamps, do not tighten
  8. Position solar panels in clamps and attach using sheet metal screws if necessary
  9. Tighten clamps and channel nuts
  10. Unite all cabling using spiders
  11. Extend spiders by 10 AWG extension cables
  12. Make holes in vent screening
  13. Feed extension cables carefully down through holes in screening
  14. Gather tools, support platform and exit roof

Assembling MC4 connectors

Do clean work with no strands of copper conductor (cable) deflected outside the bayonets. Please note that in both kinds of connector, the tightener goes over the longer segment of the bushing. Here's how to do the male connector:

  1. Disassemble male connector (the bigger one), thread the three parts in the order shown on the conductor (shown in white, from left to right):
    1. end cap
    2. tightener
    3. bushing
  2. Pare ½" insulation from the end of the conductor.
  3. Thread the male (smaller of the two bayonets) onto the end of the conductor and crimp.
  4. Press the conductor and its newly attached bayonet into the (larger of the two) connector body until it clicks.
  5. Carefully slide the three pre-threaded parts over the conductor and bayonet into the connector body.
  6. Use special MC4 wrench to tighten the end cap.

Assemble the female connector to the conductor (shown in red) using the same technique as shown in the illustration. Once finished, the two conductors can be joined together using the MC4 connector which, once connected, should provide a water-tight, ultraviolet-safe connection.

Adjustment mechanism—a study

Hell-bent on devising an adjustable system?

Here is, in concept stage only, a simple mounting mechanism to vary solar panels between 20° and 60° (for circa 40° of latitude).

You may find this more trouble than it's worth.

  1. Install two mounting rails (shown here as squares) to roof. Mounting rails are installed on pins out of roof themselves installed such as not to compromise roof integrity (none of that is shown below).
  2. Mount two connecting rails between each end of mounting rails.
  3. Anchor bottom (wired) end of panels to bottom mounting rail, allow to rotate around axis.
  4. Create floating rail (not shown) the width of all panels mounted on an articulated arm (shown) pinned to connecting rails.
  5. Install rails behind panels (not shown) on which floating rail will glide with locking points (shown). The locking points determine, with length of articulate arm, the angle of panel deflection relative to horizontal.
  6. Floating rail arm on connecting rails moves floating rail behind panels between locking points to adjust angle.
  7. Install cables or other dispositive to impede panels from being caught by wind (not shown).