Estimating in Building Construction

168 CHAPTER THIRTEEN

EXAMPLE 13-23 RIDGE

There is 52 lf of ridge from the edge of the overhang to the far
overhang.

Purchase Quantity

Size Length (lf ) Pieces

1  10 8  7



Lookouts. Lookouts are often required when a soffit is
boxed in as shown in Figure 13.52. The number of look-
outs is found by dividing the total linear feet of boxed-in
soffit by the spacing and by adding one extra lookout for
each side of the house on which it is needed. (If required,
front and back add two extra lookouts.) The length of the
lookout is found by reviewing the sections in detail. The
detail in Figure 13.52a indicates that the lookout would
be the width of the overhang minus the actual thickness
of the fascia board and the supporting pieces against the
wall. In Figure 13.52b, the lookout is supported by being
nailed to the stud wall; its length is equal to the overhang

bf 7 

1 –  10 –

12

 8 ¿47 bf

plus stud wall minus the actual thickness of the fascia

board.

Sheathing Materials. Sheathing for the roof is taken off

next. A review of the contract documents should provide the

sheathing information needed:

1. Thickness or identification index (maximum spacing of
   supports)


2. Veneer grades


3. Species grade


4. Any special installation requirements
   The sheathing is most accurately estimated by making a
   sketch of the area to be covered and by planning the sheath-
   ing sheet layout. For roof sheathing, be certain that the rafter
   length that is required is used and that it takes into consider-
   ation any roof overhang and the slope (or pitch) of the roof.
   The roof sheathing for the residence is then compiled on the
   workup sheets.
   Because the carpenters usually install the roofing felt
   (which protects the plywood or OSB until the roofers come),
   the roofing felt is taken off here or under roofing, depending
   on the estimator’s preference. Because felt, shingles, and
   built-up roofing materials are estimated in Chapter 14, that
   is where it will be estimated for this residence.

FIGURE 13.53.Plywood Sheet Layout. 

FIGURE 13.52.Lookouts.

EXAMPLE 13-24 ROOF DECKING

Refer to Figure 13.53.

Ridge length 52 ¿

Actual rafter length13.9¿

45.2 sheetsUse 46 sheets

Sheets1,446 sf of deck>32 sf per sheet

 52 ¿ ridge length1,446 sf

Square feet of roof2 sides13.9¿ rafter length