First Line Sales
PO Box 200
Vernon, VT 05354

www.firstlinesales.com

Construction Estimating Formulas & Useful Information

Formulas, equations, tables, facts, specifications and other
information useful in planning and estimating construction,
decorating and other projects.

 Measure of Dimensions, Theorem   Formulas, Rectangles, Squares, Triangles & Circles  Board Feet Concrete Estimating  Decimal and Metric Equivalents  Weights, etc.  Metrics  Energy, Electric, Insulation Drywall Estimating,  Door Handing

Cord Wood:

 A cord of wood measures 4' x 4' x 8'.  Stacked cord contains 128 cubic feet by measure.  Actually is 80 cubic feet -the rest is air.
Weighs 3,000 pounds when dry, 4,000 pounds when wet. Seasoned wood is defined as having 25% moisture content.  Four percent of its energy is lost in the evaporation process as it burns.  Green wood is defined as having 80% moisture content.  Fifteen percent of its energy is lost in the evaporation process.

Fuel energy BTU comparison:

Heating Oil 138,000 BTU per gallon (number 2 fuel oil)
Natural Gas 100,000 BTU per therm
L P gas 93,000 BTU per gallon
Mixed Hardwood 8,600 BTU per pound based on seasoned wood weighing +/- 3,000 pd. per cord.  24,000,000 BTU per cord (+/-)

Electrical formulas:  1.  Amps = Watts / Volts
                                     2.  Watts = Amps x Volts
                                     3.  Volts = Watts / Amps

Insulation:  The R-value of materials measures its resistance to heat flow.  The higher the R value, the better the resistance to heat flow.
                 The U-value is used to calculate heat loss.
Formula to find U-value is:  1 / R - value = U - value.

R-values of some common building materials:

1" Fiberglass batt,
Insulation
3.17   1" Expanded
polystyrene
4.00   1" Extruded
polystyrene
5.0
1" Polyisocyanurate,
foil-faced
7.20   8" concrete block 1.11   1' Poured concrete 0.08
1" Soft wood lumber 1.25   2x4 kds 4.38   2x6 kds 6.88
1/2" plywood 0.63   3/4" plywood 0.94   1/2" gypsum board 0.45
Window with
single glass
0.91   Windows with
IG glass 1/4" air sp.
1.69   Windows with 1/2"
Low E IG
3.13
Wood solid core
1-3/4 door
3.03   Metal ins. door
no glass
15.00   1/2" - 4" air space 1.00

                      

Temperature Formula:  Degrees Fahrenheit - 32 x 0.56 = degrees Celsius

                                    Degrees Celsius x 1.8 + 32 = Degrees Fahrenheit

Liquid:
1 ounce = 29.57 milliliters
1 quart = 0.95 liter
1 gallon = 3.79 liters

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 Measure of Dimensions, Theorem
 Formulas, Rectangles, Squares, Triangles & Circles
 Board Feet
Concrete Estimating
Decimal and Metric Equivalents
 Weights, etc.
 Metrics
 Energy, Electric, Insulation
Drywall Estimating,  Door Handing


This information is believed to be accurate.  The Polymer Roof Factory or First Line Sales will not be liable for errors and omissions.  Specifications, detail, and other information should be verified by the user.