Roof Inspections

1. Identify the roof design/components
2. Identify the roof material
3. Identify damage
4. Identify the source of ensuing damage.

Ccomponents of a typical Roof system

Types of Roof Design

1. Flat
2. Gable
3. Hip and Ridge
4. Mansard
5. Gambrel

Flat Roof - Common in commercial construction

          

The formula for a Flat Roof is:

Eave Length X Eave Width = Square footage
The formula for converting to Squares:
Total Square footage ÷ 100 = Number of Squares
30 x 90 = 2,700 square feet or 27 squares

Gable Roof - Common in residential construction

          

The formula for a Gable Roof is:

Roofs are measured in Squares / 1 square = 100 square feet
Rafter Length X Eave Length = Square footage
The formula for converting to Squares:
Total Square footage ÷ 100 = Number of Squares
14(2) x 60 = 1,680 square feet or 16.8 squares

Hip and Ridge Roof - Wind resistant

          

The formula for a Hip and Ridge Roof is:

Rafter Length X Eave Length = Square footage
The formula for converting to Squares:

Total Square footage ÷ 100 = Number of Squares
14(2) x 60 = 1,680 square feet or 16.8 squares

Intersecting Roof - Can combine Hip and Gable

          

Roof Calculations:

18(2) x 80=2880
12(2) x 10=240
Total          3120
3120 Total Square footage ÷ 100 = 31.20 squares

Gambrel Roof - Barn roof

          

The formula for a Gambrel Roof is:

Rafter Length X Eave Length = Square Footage
(15+10+10+15) x 75 = 3,750 Square footage or 37.50 squares

Mansard Roof

          

The formula for a Mansard Roof is:

Trapezoid - ((b1+b2)/2) x Height = Square Footage
Rectangle - Length X Width = Square Footage
(10+30)÷2=20      20x14=280      280x2=560
(20+60)÷2=40      40x14=560      560x2=1120
Area of Trapezoids:      560+1120=1680
Area of Rectangle:       20x20=       200
Total Area of Roof:                       1880

Common Roofing Materials

Composition Asphalt Shingles

• Organic - saturated felt with asphalt and ceramic granules.
• Glass Fiber - Asphalt with Fiberglass and ceramic granules.

The ceramic granules are to protect the shingle from the sun’s UV rays and for aesthetics.

Common types of Composition Shingles are:

• 3 Tab Shingles
• Laminate/Dimensional/Architectural
• Individual Shingles
• Roll

3 Tab and Dimensional Shingles

3 Tab Shingles
3 Bundles per square
20-25 year life span

     

Laminate and/or Dimensional Shingles
4 Bundles per square
25-35 year life expectancy

     

Architectural and Individual Shingles

Common Composition Shingles:

Architectural Shingles
4 Bundles per square
30-35 year life span

Individual Shingles
4 Bundles per square
25-35 year life expectancy

     

Wood and Metal Roofing

Other Types of Shingle Material:

1. Wood - Shake and Shingle
2. Metal - Aluminum and Steel
3. Rigid - Clay and Cement
4. Synthetic - Rubber

Wood Shakes - 5 bundles per square

Wood Shingles - 4 bundles per square

   
Metal Shingles - price by square foot

Metal Panels - price by square foot

Clay and Slate Tiles

Clay Tiles - 5 bundles per square

Slate Tiles - 5 bundles per square

Additional Roofing Material

• Ice and Water Shield
• Drip Edge

• Valley Flashing

• Gas Appliance Exhaust Vents

• Attic Ventilation


Common Commerical Roof Systems

Built up Roof (BUR)


Built up Roof with gravel


Single Ply Membranes – EPDM (Ethylene Propylene Diene Monomer)

Identify Roof Damage - typically neither hail or wind causes a leak.

Wind Damage

Hail Damage

Commercial Roof Damage

Spray Foam Roof – Hail Damage

Steel Roof – Hail Damage

Built up Roof – Hail Damage

Identify the Source of the Leak

Improper Installation

Deterioration

Repair versus Replacement

Evaluating Loss from Hail Damage

Roof - 1 layer 3 tab shingles - 5-10 years old - Reparability Factors

0-5 years -- reparability factor of .5
5-10 years -- reparability factor of 1.0
10-15 years -- reparability factor of 1.5
15+ years -- reparability factor of 2.0

Test Squares = Average of 8.5 hits per square x RF of 1.0

8.5 x 1.0 = 8.5
therefore to repair each square
8.5 (average hits per square) + 8.5 = 17 shingles per square

Roof Calculations: Total

30 x 60 = 1800 square feet
10% waste = 180 square feet
Total # squares = 1980 which rounds to 20 squares as 3 tab is sold in bundles of 3 per square

Roof Repair: Repair

18 squares x 17 shingles per square = 306 shingles to repair this roof.
306 x $11.71 per shingle = $3,583.26 cost to repair roof.

Roof Replacement

20 squares x $190.00 = $3,800 [Does not include drip edge; ice water shield, vents etc.]

Things to consider before writing the estimate

Height, Steepness and Accessibility

Material Guage

Steepness - Any roof 6/12 or greater is considered steep

Accessibility

Writing the Estimate - Terms

Square – 1 square is a 100 square feet

Linear/Lineal Feet (LF) – length of straight line

Waste – the amount of material lost during installation. [5% Felt/Rolled Roofing; 10% Gable Roof; 15% Hip and Ridge; 20% cut-up roof.

Roof Pitch – rise in inches over a 1 foot run

Unit Cost – price that includes material, labor, overhead, profit and soft costs.

Test

Cause of Loss: Hail Damage to Roof
2 box vents; 1 exhaust vent Type of Shingles: 3 Tab 15 years
Description Quantity Unit Price Replacement Cost
Remove 3 tab shingles 18 squares    

Replace 3 tab shingles

20 squares    
Replace Felt 19 squares    
Replace Ridge 60 Lineal Feet    
Remove and replace ice and water shield 360 square feet    
Remove and replace box vent 2 each    
Remove and replace exhaust vent 1 each