is custom made, the importance of good workmanship cannot be overemphasized.

In inspecting built-up roofing, you should verify the particular combination of plies, felt, binder, and cover indicated in the project specifications.

You must be sure that the felt conforms to the requirements in kind, grade, weight, and other specified characteristics and that the material is not crushed, tom, or otherwise damaged as it is used.

Likewise, ensure that the primer and binder furnished are asphalt or tar as described, that the material conforms to the specification requirements for the indicated type, and that it is kept free from water, oil, and dirt.

The standard specifications limit the material used for surfacing to gravel or slag; however, the project specifications may permit or require a special material, such as white marble chips. You must verify the types of material required or permitted and ensure that the material furnished conforms and is of suitable size, gradation, and cleanliness. No surfacing is required for roofing that calls for asbestos felt.

Where a wood roof is concerned, you must ensure the following:

That the roof deck has been prepared suitably to receive the roofing before permitting the roofing to be started.

That all large cracks and knotholes have been covered with the tin nailed in place.

That the roof is suitably smooth, clean, and dry. That felt or metal valley lining is installed in all valleys, as required for the type of roofing being used.

That the roof is covered with a layer of unimpregnated felt or resin-sized building paper and then covered with two layers of saturated felt, all lapped, nailed, mopped, and turned up or cut off at junctions with vertical surfaces, as specified.

Where concrete and similar roofs are concerned, the inspector must ensure the following:

That all cracks, voids, and rough spots are filled level and smooth with grout and are thoroughly dry.

That all sharp or rough edges are smooth.

That all loose mortar and concrete are removed and the surface is broom clean.

That felt or metal valley lining is installed in all valleys, as specified, for the type of roofing being used.

That the roof is covered with a primer of hot pitch or asphalt and then covered with two layers of saturated felt, all lapped, mopped, and turned up or cut off at junctions with vertical surfaces, as indicated. On precast gypsum or nailable concrete roofs, the specifications may require that these first two plies be nailed.

With all roofs, you must be certain that any additional layers of binder and felt are applied as required by the specifications. You must make sure that each lap and layer are mopped full width with the specified quantity of hot binder, without gaps, so that felt nowhere touches felt; that the binder is applied at a temperature within the specified range and no burnt tar or asphalt is used; and that these layers are turned up, as indicated. You must be sure that the entire finished surface is uniformly coated with binder poured on at the specified rate and then covered with the required quantity and kind of covering material. You must make sure that all roofing is free from wrinkles, air or water bubbles, and similar irregularities and that all plies are firmly cemented together.

TRIM

There are basically three types of trim, and these are metal, wood, and plastic. Since plastics and metal are seldom used in the Navy, we will cover only wood trim.

Wood trim or millwork may be of either rare or common varieties of hard or softwood. Regardless of species, millwork usually must be thoroughly seasoned, air-dried or kiln-dried, free from knots and sap, and must be of an even, straight grain.

As the inspector, you must make sure that the trim has been factory-inspected or grade-marked and is of the species, grade, dimensions, pattern, and finish prescribed; that molded lines are true and sharp without fuzz, flats, or splintered edges; and that the material has been suitably dried and is not warped or curled.

You must make certain that the installation of wood trim is made with the specified quality of workmanship. On high-grade work, the inspector must ensure the following:

That all trim is set plumb with square comers.

That all corners are miter cut and coped, if necessary, for close fit on internal comers, and provision is made for expansion and shrinkage.