_Roofing Calculator
All materials in this section are BP roofing and available at Malone Lumber. To vist BP online, or to look at available colors, click here.

_Shingles:  

Roofs come in many different styles and sizes. To determine how many shingles are required, we must first obtain the area of the surface to be covered. In general, a roof can be defined by a series of rectangles, triangles, parallelograms and even cones. In the fields provided below enter the required information for the roof you are covering. Each area will be added to a running total. You can enter as many areas as you require, such as  two rectangles of one size then 3 of another size and 4 of another size. For example: a typical gable roof consists of two identical rectangles, while a simple cottage style might consist of two trapezoids and two triangles. Each click of a CALC button will compute the area of the component entered and each click of the ADD to TOTAL button will add the newly calculated value to your roof total area.  Each entry is listed in the summary box below.

  Find the area of your roof using:   

A Rectangle
Length Height

Number of:

rectangles

Length * Height


A triangle
Length Height

triangles

Length * Height / 2


A trapezoid
Length Top
Length Bottom
Height

trapezoids

Top + Bottom / 2 * Height


A parallelogram
Length Height

parallelograms

Length * Height


A Cone

Radius of Base

Length of side

cones

pi.gif (836 bytes) * Radius * Side


 

TOTAL AREA  OF SHINGLE TYPE

TOTAL BUNDLES OF SHINGLES REQUIRED, INCLUDES 10% ALLOWANCE FOR STARTER STRIP, HIPS, RIDGES AND WASTE
BUNDLES

_Eave Protector  

Eave protector should be laid from the eaves to a point a minimum of 12" beyond the inside of the exterior wall line. On decks having a slope between 2" to 4" per foot (1:6 to 1:3), eave protector should be laid extending up the roof, from the eaves to a point at least 24" (61 cm) beyond the interior wall. line.

Length of eave    / (65 ft/roll or 19.8 m/roll) * Number of courses required to meet the above specification including any overlap.

=  Rolls required

_Drip Edge:  

Note: standard length 10 ft or 3 m., if another size is to be used enter as appropriate.

Circumference of total roof edge / length of drip edge =

Lengths required

_Underlayment:  

The underlayment covers the surface of the roof not covered by the eave protector

Area of the roof - ( Number or rolls of eave protector * (195 ft²/roll or 18.1 m²/roll) ) /  (400 ft²/roll or 37.2 m²/roll)

= Rolls required

_Vents:  

1 ft2 of ventilation is required for every 300 ft2 or 27.9 m2 of attic space, to be split evenly between roof ventilation and soffit ventilation.

area of attic space / 300 ft2 or  27.9 m2

of ventilation required

_Flashings:  

Vinyl or metal  ( galvanized steel, sheet copper) shall be installed around chimneys, vents, soil stacks, etc

_Drip Edge:  

Should be used for chimney flashing, soil stack flashing, exposed nails on vents, and valleys. It is essential that cement be applied with caution and always according to the instructions on the label.

_Summary of Estimations:  

Obtain prices by calling 483-3460 or (800)800 - MLRM.

SHINGLES Bundles per bdl
EAVE PROTECTOR Rolls per roll
DRIP EDGE Pieces per pc
UNDERLAYMENT Rolls per roll
VENTS (and SOFFIT) Pieces (1ft²) per pc
FLASHINGS Pieces per pc
ROOFING CEMENT Units per unit


*note - Formulas for calculations curtesy of Emco BP Roofing Corporation.