Design Basic's

1 | PV INCOMPATIBLE ROOF TYPES

OVERVIEW

The following roof membrane types are incompatible for PV installations at ION. These roof types will automatically constitute a reroof:

Wood Shake Roof
Aluminum Shingle Roof
Stone Coated Steel Tile (Decra or Cal-Pac)
Clay Tile Roof (not to be confused with concrete tile)
Slate Tile

Light Reach (PPA) Disqualified Roof Types:

Clay Tile Roof
Metal Shingle (including asphalt and stone coated)
Wood and Cal Shake
Tar & Gravel
Copper or Tin Metal
Cal Pac
SIP

Wood Shake

Aluminum Shingle

Slate tile

Clay Tile

Cal-pac

Decra

Reroof and Misc work

MORE THAN 2 LAYERS OF ROOFING MATERIAL

Two layers is the maximum allowable layers of shingles for a roof according to building codes. When you see more than 2 layers:

A reroof will be needed.
Surveyor must get on the top of the ladder for every comp shingle job and check the number of layers and take a photo.
How you determine how many it is, is to count the base lay then each layer on top of that. (see example)

There are no exceptions to this rule.

2018 IRC R908.3.1.1(3) Roof recover not allowed: Where the existing roof has two or more applications of any type of roof covering [a roof recover will not be allowed]

The Why
Roofs are only capable of holding so much weight, and adding a second layer of roofing materials pushes it that much closer to its threshold. While on an average day two layers of roofing may not be enough to cause your roof to collapse, in the event of heavy ice, snow, or debris, the extra weight (OR adding solar) of the second layer could very well be enough that you find yourself faced with a caved-in roof. Unfortunately, many insurance companies will not cover this since they can put the blame on the extra weight and not on the elements themselves.

MOSS

This should be done prior to install and is the customer obligation to clean it. If it hasn't been done the we need to reach out to DV and Sales liasons.

The why

Moss acts like a sponge, absorbing large amounts of moisture and resulting in your roof being constantly wet. Causing a slipping hazard to our installers.

2 | COMPATIBLE ROOF MEMBRANE TYPES

OVERVIEW

The following roofing materials are compatible for PV installations at ION:

Composition Shingle
Concrete Tile
Sheet Metal
Flat Roof Membranes

3 | BASIC ROOF COMPOSITION

ROOF LAYERS

The first thing to be familiar with when screening for roof damage is the basics of roof anatomy. Mainly, what we care about is the roof membrane itself, underlayment and sheathing.

Layers from bottom to top:
Roof sheathing
Underlayment
Ice and Water Shield
Flashing
Roofing material (Roof Membrane)

Roof Damage

1) GENERAL DAMAGE - COMPOSITION SHINGLE

Shingle roofs will be the main culprit for damage and wear when reviewing roof photos. By far, more re-roofs and repairs will be requested for shingle roofs than any other roof membrane type. If the roof has 2-5 years left, then its good for solar!

Watch out for general signs of wear:

Shingles have bare spots with no granules
Buckling / Curling shingles
Signs of severe hail damage
Cracking
Frayed Edges
Busted Ridge Caps

This is an example of a missing ridge cap.

Note the overall condition of the rest of the visible roof is also pretty bad.

This is an example of a cracked ridge cap.

Cracking can appear anywhere on the roof, not just the ridge cap.
This usually indicates that the shingles have weathered and dry such that they are now brittle.

This is an example of a hail damage

There are bald spots on shingles where grit is missing from where larger hail has impacted the roof.

This is an example of worn shingles

If you can see the fiberglass edges of the shingles, it is an indicator that the roof needs to be replaced.

QUIZ TIME!!!!

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