Estimating in Building Construction

Thermal and Moisture Protection 185

The usual wide variety of materials and finishes is avail-
able in trim. Not all trim is standard stock; much of it must
be specially formed and fabricated, which adds considerably
to the cost of the materials and to the delivery time. Estima-
tors must be thorough and never assume that the trim
needed is standard stock.

14–22 Labor

The labor cost of roofing will depend on the hourly output
and hourly wages of the workers. The output will be gov-
erned by the incline of the roof, size, irregularities in the
plan, openings (skylights, etc.), and the elevation of the roof
above the ground since the higher the roof, the higher the
materials have to be hoisted to the work area.
Costs can be controlled by the use of crews familiar with
the type of work and experienced in working together. For this
reason, much of the roofing done on projects is handled by a
specialty contractor with equipment and trained personnel.

14–23 Equipment

Equipment requirements vary considerably, depending on
the type of roofing used and the particular job being esti-
mated. Most jobs will require hand tools for the workers,
ladders, some scaffolding, and some type of hoist, regardless
of the type of roofing being applied. Specialty equipment for
each particular installation may also be required. Built-up
roofing may demand that mops, buggies, and heaters (to
heat the bituminous materials) be used; some firms have

either rotary or stationary felt layers. Metal roofing requires

shears, bending tools, and soldering outfits.

Equipment costs are estimated either by the square or by

the job, with the cost including such items as transportation,

setup, depreciation, and replacement of miscellaneous items.

14–24 Checklist

Paper Flashing

Felt Ridges

Composition (roll) Valleys

Composition (built-up) Fasteners

Tile (clay, metal, concrete) Trim

Shingles (wood, asphalt, slate) Battens

Metal (copper, aluminum, Blocking (curbs)

corrugated, steel) Cant strips

Insulation Waterproofing:

Base integral

Solder: membrane

paints Dampproofing:

plaster integral

foundation walls parge

slabs vapor barriers

sump pits bituminous materials

protective materials drains

exterior foundation walls

interior slabs

admixtures

drains

Web Resources

http://www.nrca.net

http://www.asphaltroofing.org

http://www.roofhelp.com

Review Questions

1. What is the difference between waterproofing and
   dampproofing?


2. What is membrane waterproofing, and how is it estimated?


3. What is parging, and what unit of measure is used?


4. What is the unit of measure for roll batt insulation? What
   type of information should be noted on the estimate?


5. What is the unit of measure for shingle roofing? What
   type of information should be noted on the estimate?
   6. What is the unit of measure for built-up roofing?
   What type of information should be noted on the
   estimate?
   7. Determine the amount of dampproofing required for
   the building in Appendix C.
   8. Assume that membrane waterproofing is required
   under the slab for the building in Appendix C. Deter-
   mine the material required if a three-ply system is
   specified under the floor slab and up the walls within
   2 inches of grade.
   9. Determine the amount of insulation required for the
   walls and ceiling for the building in Appendix C.


6. Determine the amount of cant strips and other acces-
   sories required on the building in Appendix C.


7. Determine the amount of built-up roofing, slag, and
   flashing required for the building in Appendix C.

pumps