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 Chapter 4: Building Aspects of a Housing 

 Inspection

Table of Contents

I. Background Factors

II. Housing Construction Terminology

III. Structure

IV. Discussion of Inspection Techniques

V. Noise as an Environmental Stress

The principle function of a house is to furnish protection from the elements. In its current stage, however, our civilization requires 

that a home provide not only shelter but also privacy, safety, and reasonable protection of our physical and mental health. A 

living facility that fails to offer these essentials through adequately designed and properly maintained interiors and exteriors

cannot be termed "healthful housing."

I. Background Factors

In this chapter, a building will be considered in terms of its major components: heating, plumbing, and electrical systems. Each of 

these items will be examined in detail in future chapters. Attention will be given in this chapter to the portions of a building not 

visible upon completion of the ceiling, roof, and interior and exterior walls in order to give the reader an understanding of 

generally accepted construction practices. Emphasis, however, will be placed upon the visible interior and exterior parts of a 

completed dwelling that have a bearing on the soundness, state of repair, and safety of the dwelling both during intended use and 

in the event of a fire. These are some of the elements that the housing inspector must examine when making a thorough housing 

inspection.

II. Housing Construction Terminology

(Key to Component Parts Numbered in Figure 4-1)

Figure 4-1. Housing Construction Terminology

A Fireplace

1. Chimney - A vertical masonry shaft of reinforced concrete or other approved noncombustible, heat resisting material 

enclosing one or more flues. It removes the products of combustion from solid, liquid, or gaseous fuel. 

2. Flue Liner - The flue is the hole in the chimney. The liner, usually of terra cotta, protects the brick from harmful smoke 

gases. 

3. Chimney Cap - This top is generally of concrete. It protects the brick from weather. 

4. Chimney Flashing - Sheet-metal flashing provides a tight joint between chimney and roof. 
5. Firebrick - An ordinary brick cannot withstand the heat of direct fire, and so special firebrick is used to line the fireplace. 

6. Ash Dump - A trap door to let the ashes drop to a pit below, from where they may be easily removed.

7. Cleanout Door - The door to the ash pit or the bottom of a chimney through which the chimney can be cleaned. 

8. Chimney Breast - The inside face or front of a fireplace chimney. 

9. Hearth - The floor of a fireplace that extends into the room for safety purposes. 

B Roof 

10. Ridge - The top intersection of two opposite adjoining roof surfaces. 

11. Ridge Board - The board that follows along under the ridge. 

12. Roof Rafters - The structural members that support the roof. 

13. Collar Beam - Really not a beam at all. A tie that keeps the roof from spreading. Connects similar rafters on opposite side 

of roof. 

14. Roof Insulation - An insulating material (usually rock wool or fiberglass) in a blanket form placed between the roof rafters 

for the purpose of keeping a house warm in the winter, cool in the summer. 

15. Roof Sheathing - The boards that provide the base for the finished roof. 

16. Roofing - The wood, asphalt, or asbestos shingles - or tile, slate or metal - that form the outer protection against the 

weather. 

17. Corner Bracing - Diagonal strips to keep the frame square and plumb. 

18. Sheathing - The first layer of outer wall covering nailed to the studs. 

19. Joist - The structural members or beams that hold up the floor or ceiling, usually 2x10's or 2x12's spaced 16 inches apart. 

20. Bridging - Cross bridging or solid. Members at the middle or third points of joist spans to brace one to the next and to 

prevent their twisting. 

21. Subflooring - The rough boards that are laid over the joist. Usually laid diagonally. 

22. Flooring Paper - A felt paper laid on the rough floor to stop air infiltration and, to some extent, noise. 

23. Finish Flooring - Usually hardwood, of tongued and grooved strips. 

24. Building Paper - Paper placed outside the sheathing, not as a vapor barrier, but to prevent water and air from leaking in. 

Building paper is also used as a tarred felt under shingles or siding to keep out moisture or wind. 

25. Beveled Siding - Sometimes called clapboards, with a thick butt and a thin upper edge lapped to shed water. 

26. Wall Insulation - A blanket of wool or reflective foil placed inside the walls. 

27. Metal Lath - A mesh made from sheet metal onto which plaster is applied. 

D Foundation and Basement 
28. Finished Grade Line - The top of the ground at the foundation. 

29. Foundation Wall - The wall of poured concrete (shown) or concrete blocks that rests on the footing and supports the 

remainder of the house . 

30. Termite Shield - A metal baffle to prevent termites from entering the frame. 

 

31. Footing - The concrete pad that carries the entire weight of the house upon the earth. 

32. Footing Drain Tile - A pipe with cracks at the joints to allow underground water to drain in and away before it gets into 

the basement. 

33. Basement Floor Slab - The 4 or 5-inch layer of concrete that forms the basement floor. 

34. Gravel Fill - Placed under the slab to allow drainage and to guard against a damp floor. 

35. Girder - A main beam upon which floor joists rest. Usually of steel, but also of wood. 

36. Backfill - Earth, once dug out, that has been replaced and tamped down around the foundation. 

37. Areaway - An open space to allow light and air to a window. Also called a light well. 

38. Area Wall - The wall, of metal or concrete, that forms the open area. 

 

E Windows and Doors 

39. Window -An opening in a building for admitting light and air. It usually has a pane or panes of glass and is set in a frame 

or sash that is generally movable for opening and shutting. 

40. Window Frame - The lining of the window opening. 

41. Window Sash - The inner frame, usually movable, that holds the glass. 

42. Lintel - The structural beam over a window or door opening. 

43. Window Casing - The decorative strips surrounding a window opening on the inside. 

 

F Stairs and Entry 

44. Entrance Canopy - A roof extending over the entrance door. 

45. Furring - Falsework or framework necessary to bring the outer surface to where we want it. 

46. Stair Tread - The horizontal strip where we put our foot when we climb up or down the stairs. 

47. Stair Riser-The vertical board connecting one tread to the next. 

48. Stair Stringer - The sloping board that supports the ends of the 

steps. 

49. Newel - The post that terminates the railing. 

50. Stair Rail - The bar used for a handhold when we use the stairs. 
51. Balusters - Vertical rods or spindles supporting a rail. 

 

III. Structure

A Foundation

The word foundation is used to mean:

1. Construction below grade such as footings, cellar or basement walls. 

2. The composition of the earth on which the building rests. 

3. Special construction such as pilings and piers used to support the building.

The foundation bed may be composed of solid rock, sand, gravel, or unconsolidated sand or clay. Rock, sand, or gravel are the 

most reliable foundation materials. Unconsolidated sand and clay, though found in many sections of the country, are not as 

desirable. because they are subject to sliding and settling.

The footing (see Figure 4-2) distributes the weight of the building over a sufficient area of ground so as to ensure that the 

foundation walls will stand properly. Footings are usually constructed of a masonry-type material such as concrete; however, in 

the past wood and stone have been used. Some older houses have been constructed without footings.

Although it is usually difficult to determine the condition of a footing without excavating the foundation, a footing in a state of 

disrepair or lack of a footing will usually be indicated either by large cracks or by settlement in the foundation walls (see Figure 

4-3).

Figure 4-2. Foundation Details

Figure 4-3. Foundation Cracks

Foundation wall cracks are usually diagonal, starting from the top, the bottom, or the end of the wall. Cracks that do not extend 

to at least one edge of the wall may not be caused by foundation problems. Such wall cracks may be due to other structural 

problems and should also be reported.

The foundation walls support the weight of the structure and transfer this weight to the footings. The foundation walls may be 

made of stone, brick, concrete, or concrete blocks and should be moisture proofed with either a membrane of water-proof 

material or a coating of portland cement mortar. The membrane may consist of plastic sheeting or a sandwich of standard roofing 

felt joined and covered with tar or asphalt. The purpose of water-proofing the foundation walls is to prevent water from 

penetrating the wall material and leaving the basement or cellar walls damp.

Holes in the foundation walls are a common finding in many old houses. These holes may be caused by missing bricks or blocks. 

Holes and cracks in a foundation wall are undesirable because they make a convenient entry for rats and other rodents and also 

indicate the possibility of further structural deterioration. These holes should not be confused with adequately installed vents in 

the foundation wall that permit ventilation and prevent moisture entrapment.

The basement or cellar floor should be made of concrete placed on at least 6 inches of gravel. The purpose of a concrete floor is to 

protect the basement or cellar from invasion by rodents or from flooding. The gravel distributes ground water movements under 

the concrete floor, reducing the possibility of the water's penetrating the floor. A waterproof membrane, such as plastic sheeting, 

should be laid before the concrete is placed for additional protection against flooding.

The basement or cellar floor should be gradually but uniformly sloped towards a drain or a series of drains from all directions.

These drains permit the basement or cellar floor to be drained if it becomes flooded .
Evidence of ineffective waterproofing or moisture proofing will be indicated by water or moisture marks on the floor and walls.

Cellar doors, hatchways, and basement windows should be weathertight and rodent proof. A hatchway can be inspected by 

standing at the lower portion with the doors closed; if daylight can be seen, the door probably needs repair.

B Framing

Many different types of house-farming systems are found in various sections of the country; however, the majority of the 

members in each framing system are the same. They include:

1. Foundation Sills: (see Figure 4-4 and 4-5). The purpose of the sill is to provide support or a bearing surface for the 

outside walls of the building. The sill is the first part of the frame to be placed and rests directly on the foundation wall. It is 

bolted to the foundation wall by sill anchors. It is good practice to protect the sill against termites by extending the 

foundation wall to at least 18 inches above the ground and using a noncorroding metal shield continuously around the 

outside top of the foundation wall. 

2. Flooring Systems: (see Figure 4-5). The flooring system is composed of a combination of girders, joists, sub-flooring, and 

finished flooring that may be made up of concrete, steel, or wood. Joists are laid perpendicular to the girders, at about 16 

inches on centers, and are the members to which the sub-flooring is attached. When the subfloor is wood, it may be nailed 

at either right angles or diagonally to the joists.

As shown in Figure 4-5, a girder is a member that in certain framing systems supports the joists and is usually a larger 

section than the joists it supports. Girders are found in framing systems where there are no interior bearing walls or where 

the span between bearing walls is greater than the joists are capable of spanning. The most common application of a girder 

is to support the first floor in residences. Often a board known as a ledger is applied to the side of a wood girder or beam to 

form a ledge for the joists to rest upon. The girder, in turn, is supported by wood posts or steel "lally columns" which 

extend from the cellar or basement floor to the girder. 

3. Studs: (see Figure 4-4 and 4-5). Wall studs are almost always 2 by 4 inches; studs 2 by 6 inches are occasionally used to 

provide a wall thick enough to permit the passage of waste pipes. There are two types of walls or partitions: bearing and 

nonbearing. A bearing wall is constructed at right angles to and supports the joists. A nonbearing wall or partition acts as a 

screen or enclosure; hence, the headers in it are often parallel to the joists of the floor above.

Figure 4-4. Wall Framing

Figure 4-5. Floor Construction

In general, studs like joists are spaced 16 inches on center. In light construction such as garages and summer cottages 

where plaster is omitted, or some other material is used for a wall finish wider spacing on studs is common.

Openings for windows or doors must be framed in studs. This framing consists of horizontal members called "headers," and 

vertical members called "trimmers" (see Figure 4-l).

Since the vertical spaces between studs can act as flues to transmit flames in the event of a fire, ''fire stops" are important 

in preventing or retarding fire from spreading through a building by way of air passages in walls, floors, and partitions. Fire 

stops are wood obstructions placed between studs or floor joists to prevent fire from spreading in these natural fluespaces.

4. Interior Wall Finish: Many types of materials are used for covering interior walls and ceilings, but the principal types are 

plaster and dry-wall construction. Plaster is a mixture, usually lime, sand, and water, applied in two or three coats to lath to

form a hard-wall surface. Dry-wall finish is a material that requires little, if any, water for application. More specifically, drywall finish may be gypsum board, plywood, fiberboard, or wood in various sizes and forms.
Gypsum board is a sheet material composed of a gypsum filler faced with paper. Sheets are usually 4 feet wide and can be 

obtained in lengths up to 12 feet. In dry-wall construction, gypsum boards are fastened to the studs either vertically or 

horizontally and then painted. The edges along the length of the sheet are recessed to receive joint cement and tape.

A plaster finish requires a base upon which plaster can be spread. Wood lath at one time was the plaster base most 

commonly used, but today gypsum-board lath is more popular. It has paper faces with a gypsum filler. Such lath is 16 by 

48 inches and 1/2 or 3/8 inches thick.

It is applied horizontally across the studs. Gypsum lath may be perforated to improve the bond and thus lengthen the time 

the plaster can remain intact when exposed to fire. The building codes in some cities require that gypsum lath be 

perforated. Expanded-metal lath may also be used as a plaster base. Expanded-metal lath consists of sheet metal slit and 

expanded to form openings to hold the plaster. Metal lath is usually 27 by 96 inches and is fastened to the studs.

Plaster is applied over the base to a minimum thickness of 1/2 inch. Because some drying may take place in wood-framing 

members after the house is completed, some shrinkage can be expected, which, in turn, may cause plaster cracks to 

develop around openings and in corners. Strips of lath imbedded in the plaster at these locations prevent cracks.

On the inside face of studs that form an exterior wall, vapor barriers are used to prevent condensation on the wall. The 

vapor barrier is an asphalted paper or metal foil through which moisture-laden air cannot travel.

5. Stairways: (see Figure 4-6). The general purpose of the standards for stairway dimensions is to ensure that there is 

adequate headroom, width, and uniformity riser and tread size of every step to accommodate the expected traffic on each 

stairway safely.

Interior stairways should be not less than 44 inches in width. The width of a stairway may be reduced to 36 inches in oneand two-farnily dwellings. Stairs with closed risers should have maximum risers of 8? inches and a minimum tread of 9 

inches plus 1 ?-inch nosing. Basement stairs are often constructed with open risers. These stairs should have maximum 

risers of 8? inches and minimum treads of 9 inches plus ?-inch nosing. The headroom in all parts of the stair enclosure 

should be no less than 80 inches.

Exterior stairway dimensions should be the same as those called for in interior stairways, except that the headroom 

requirement does not apply.

Figure 4-6. Stairway

6. Windows: The four general classifications of windows for residences are:

a Double-hung sash window that moves up or down, balanced by weights hung on chains or ropes, or springs on each side.

b Casement window sash is hinged at the side and can be hung so that it will swing outward or inward.

c Awning window-usually has two or more glass panes that are hinged at the top and swing about a horizontal axis.

d Sliding window - usually has two or more glass panes that slide past one another on a horizontal track.

The principal parts of a double-hung window (see Figure 4-7) are the lights, the top rail framing members, bars or muntins that 

separate the lights, stiles - side-framing members, bottom rail, sash weights, and sash cords or chains. (All rails are horizontal, all 

stiles vertical.) The casement window's principal parts include: top and bottom rails, muntins, butt hinges, and jamb. All types of 

windows should open freely and close securely.

The exterior sill is the bottom projection of a window. The drip cap is a separate piece of wood projecting over the top of the 

window and is a component of the window casing.
Figure 4-7. Window Details

Doors: There are many styles of doors both for exterior and interior use. Interior doors should offer a reasonable degree of 

privacy. Exterior doors must, in addition to offering privacy, protect the interior of the structure from the elements. The various 

parts of a door have the same definitions as the corresponding parts of a window.

The most common types of doors are:

a Batten door: This consists of boards nailed together in various ways. The simplest is two layers nailed to each other at right 

angles, usually with each layer at 4; degrees to the vertical.

Another type of batten door consists of vertical boards nailed at right angles to several (two to four) cross strips called ledgers, 

with diagonal bracing members nailed between ledgers. If vertical members corresponding to ledgers are added at the sides, the 

verticals are called frames.

Batten doors are often found in cellars and other places where appearance is not a factor and economy is desired.

b Flush doors: Solid flush doors are perfectly flat, usually on both sides, although occasionally they are made flush on one side 

and paneled on the other. Flush doors sometimes are solid planking, but they are commonly veneered and possess a core of small 

pieces of white pine or other wood. These pieces are glued together with staggered end joints. Along the sides, top, and bottom 

are glued 32-inch edge strips of the same wood, used to create a smooth surface that can be cut or planed. The front and back 

faces are then covered with a 1/8- to 1/4-inch layer of veneer.

Solid flush doors may be used on both the interior and exterior.

c Hollow - core doors: These, like solid flush doors, are perfectly flat, but unlike solid doors, the core consists mainly of a grid of 

crossed wooden slats or some other type of grid construction. Faces are 3-ply plywood instead of one or two plies of veneer, and

the surface veneer may be any species of wood, usually hardwood. The edges of the core are solid wood and are made wide 

enough at the appropriate places to accommodate locks and butts. Doors of this kind are considerably lighter than solid flush 

doors.

Hollow-core doors are usually used as interior doors.

d Paneled doors: Most doors are paneled, with most panels consisting of solid wood or plywood, either "raised" or "flat," 

although exterior doors frequently have one or more panels of glass, in which case they are called "lights." One or more panels 

may be employed although the number seldom exceeds eight. Paneled doors may be used both on the interior or exterior.

In addition to the various types of wood doors, metal is often used as veneer or for the frame.

In general, the horizontal members are called rails and the vertical members are called stiles. Every door has a top and bottom 

rail, and some may have intermediate rails. There are always at least two stiles. one on each side of the door.

The frame of a doorway is the portion to which the door is hinged. It consists of two side jambs and a head jamb, with an integral 

or attached stop against which the door closes.

Exterior door frames are ordinarily of softwood plank, with side rabbitted to receive the door in the same way as casement 

windows. At the foot is a sill, made of hardwood to withstand the wear of traffic, and sloped down and out to shed water.

Interior door frames are similar to exterior, except that they are often set directly on the hardwood flooring without a sill.

Building codes throughout the country call for doors in various locations within the structure to be fire resistant. These doors are 
often covered with metal or some other fire-resistant materials. and some are completely constructed of metal. Fire-resistant 

doors are usually located between a garage and a house, stairwells and hallways, all boiler rooms. The fire resistance rating 

required for various doors differs with local fire codes

C Roof Framing (see Figures 4-1,4-4,4-8, and 4-9)

Rafters serve the same purpose for the roof as joists do for floors, i.e., providing support for sheathing and roofing material.

Rafters are usually spaced 20 inches on center.

1. Collar Beam: Collar beams are ties between rafters on opposite sides of the roof. If the attic is to be used for rooms, the 

collar beam may double as the ceiling joist. 

2. Purlin: A purlin is the horizontal member that forms the support for the rafters at the intersection of the two slopes of a 

gambrel roof. 

3. Ridge Board: A ridge board is a horizontal member against which the rafters rest at their upper ends; it forms a lateral tie 

to make them secure 

4. Hip: Like a ridge except that it slopes. The intersection of two adjacent, rather than two opposite, roof planes. 

5. Roof Boards: The manner in which roof boards are applied depends upon the type of roofing material. Roof boards may vary 

from tongue-and-groove lumber to plywood panels. 

6. Dormer: The term dormer window is applied to all windows in the roof of a building, whatever their size and shape.

D Exterior Walls and Trim (see Figure 4-4 and 4-9) Exterior walls are enclosure walls whose purpose is to make the building 

weather-tight. In most one- to three-story buildings they also serve as bearing walls. These walls may be made of many different

materials.

Frequently used framed exterior walls appear to be of brick construction. In this situation, the brick is only one course thick and is 

called a brick veneer. It supports nothing but itself and is kept from toppling by ties connected to the frame wall.

In frame construction the base material of the exterior walls is called "sheathing." The sheathing material may be square-edge, 

shiplap, or tongue-and-groove boards.

In recent construction there has been a strong trend toward the use of plywood or composition panels.

Sheathing, in addition to serving as a base course for the finished siding material, stiffens the frame to resist sway caused by

wind. It is for this reason that sheathing has been applied diagonally on frame buildings.

The finished siding may be clapboard, shingles, aluminum, brick asphalt, wood, and so forth, or a combination thereof. Good 

aluminum siding has a backer board that serves as added insulation and affords rigidity to the siding. Projecting cornices are a

decorative trim found at the top of the building's roofline. A parapet wall is that part of the masonry wall that extends up and

beyond the roofline and is capped with a noncombustible material. It helps prevent spread of fire, provides a rest for fire 

department ladders, and helps prevent people on the roof from falling off.

Many types of siding, shingles, and other exterior coverings are applied over the sheathing. Wood siding, cedar, and other wood 

shingles or shakes, clapboard, common siding (called bevel siding), composition siding, asbestos, cement shingles, asbestoscement siding, and the aforementioned aluminum siding are commonly used for exterior coverings. Clapboards and common 

siding differ only in the length of the pieces. Clapboards are 4 feet long while panel siding comes in lengths from 6 to 16 feet. 

Composition siding is made of felt and asphalt, which are often shaped to look like brick. Asbestos and cement shingles are rigid 

and produce a covering that is fire resistant. Cedar wood shingles are also manufactured with a backer board that gives insulation 

and fire-resistant qualities. Asbestos cement siding made of asbestos fiber and portland cement has good fire-resistant qualities 

and is a rigid covering.
E Roof Coverings (Flexible Material Class)

1. Asphalt Shingle: The principal damage to asphalt shingle roofs is caused by the action of strong winds on shingles nailed 

too high. Usually the shingles affected by winds are those in the four or five courses nearest the ridge and in the area 

extending about 5 feet down from the edge or rake of the roof.

2. Asphalt Built-up Roofs: These may be unsurfaced, the coating of bitumen being exposed directly to the weather, or they 

may be surfaced having slag or gravel imbedded in the bituminous coating. The use of surfacing material is desirable as a 

protection against wind damage and the elements. This type of roof should have enough pitch to drain water readily.

3. Coal Tar Pitch Built-up Roofs: This type roof must be surfaced with slag or gravel. Coal tar pitch built-up roof should 

always be used on deck pitched less than 34 inch per foot; that is, where water may collect and stand. This type roof should 

be inspected on completion, 6 months later, and then at least once a year, preferably in the fall. When the top coating of 

bitumen shows damage or has become badly weathered, it should be renewed (rigid material class).

4. Slate Roofs: The most common problem with slate roofs is the replacement of broken slates. Roofs of this type normally 

render long service with little or no repair.

5. Tile Roofs: Replacement of broken shingle tiles is the main maintenance problem. This is one of the most expensive 

roofing materials. It requires very little maintenance and gives long service.

6. Copper Roofs: Usually are of 16-ounce copper sheeting and applied to permanent structures. When properly installed, they 

require practically no maintenance or repair. Proper installation allows for expansion and contraction with changes in 

temperature.

7. Galvanized Iron Roofs: Maintenance is done principally by removing rust and keeping roof well painted. Leaks can be 

corrected by renailing, caulking, or replacing all or part of the sheet or sheets in disrepair.

8. Wood Shingle Roofs: The most important factors of this type roof are its pitch and exposure, the character of wood, kind 

of nails used, and preservative treatment given shingles. Creosote and coal tar preservative are satisfactory for both treated 

and untreated shingles.

9. Flashing: Valleys in roofs that are formed by the junction of two downward slopes may be finished, open, or closed. In a 

closed valley the slates, tiles, or shingles of one side meet those of the other. and the flashing below them may be 

comparatively narrow. In an open valley, the flashing, which may be made of zinc, copper, or aluminum, is laid in a 

continuous strip, extending 12 to 18 inches on each side of the valley, while the tiles or slates do not come within 4 to 6 

inches of it.

The ridges built up on a sloping roof where it runs down against a vertical projection, like a chimney or a skylight, should be 

weatherproofed with flashing.

Metal flashings are generally used with slate, tile, metal, and wood shingles. Failure of roof flashing is usually due to 

exposed nails that have come loose. The loose nails allow the flashing to lift with leakage resulting.

10. Gutters and Leaders: Gutters and leaders should be of noncombustible materials. They should be securely fastened to the 

structure and spill into a storm sewer if the neighborhood is so provided. When there is no storm sewer, a concrete or stone 

block placed on the ground beneath the leader prevents water from eroding the lawn. This store block is called a splash 

block. Gutters will not become plugged if protected against clogging of leaves and twigs. Gutters should be checked every 

spring and fall and then cleaned out when necessary.

Figures 4-8 & 4-9 Cornice Construction.
IV. Discussion of Inspection Techniques

A serious building defect may often be observed during a housing inspector's routine examination. In many cases it is beyond the

scope of the housing inspector's background to analyze the underlying causes and to recommend a course of action that will 

facilitate repair in an efficient and economical manner. In situations such as this, it is important that the inspector realize his 

limitations and refer the matter to the proper expert.

A prime example of a technically complex situation that a housing inspector might observe is a leaning, buckling, or bulging 

foundation or bearing wall. This problem may be the result of a number of hidden or interacting problems. For example, it may be

the result of differential building settlement or failure of a structural beam or girder. It is beyond the scope of the housing 

inspector's responsibilities to discover the cause of the defect, but it is his responsibility to note the problem and refer it to the 

proper authority. In this case the proper authority would be a building inspector.

In the aforementioned situation where a bulging foundation wall was discovered, this would obviously constitute a violation of the 

housing ordinance and should be written up as such by the housing inspector. Since the housing inspector is generally not 

qualified to determine whether the house should be evacuated because it is in danger of imminent collapse, he should seek the 

advice of a building inspector.

A question that frequently arises is which violations should be referred to an expert? Needless to say, circumstances that 

obviously fall within the jurisdiction of another department should be referred to the department. The housing inspector should 

discuss with his supervisor any situation in which he feels inadequate to make a decision. In all cases the inspector should inform 

his supervisor before referring a problem to another agency or expert.

Another reason for referral to other departments is that when a remedial action is completed the other department will be in a 

better position to determine whether the job is satisfactory.

This principle of referral should be applied to every portion of the inspection, whether it deals with health, heating, plumbing, gas, 

or electrical as well as structural defects.

Certain structural items should be recognized as unsafe by the housing inspector. For example, a beam that has sagged or slanted

may cause a portion of or an entire floor to sag or slope. Where a sagging or sloping floor is found, examine the ceiling of the

room below or the basement for a broken or dropped girder or joist.

Doors and windows that are out of level will not close completely. It may be possible to see outside light through openings around 

window rails and door jambs. If an inspector detects such a situation, the condition of the supporting girders, girts, posts, and 

studs should be questioned, since this condition is evidence that some of these members may be termite infested or rotted and 

may be causing the outside wall to sag. Glass panes in doors and windows should be replaced if found to be broken or missing. 

Windows should also be checked for proper operation, and items such as broken sash cords or chains noted.

If the roof of the structure appears to be sagging, the inspector should make a special effort to examine the rafters, purlin, collar 

beams, and ridge boards if these members are exposed as in unfinished attics. The condition of the roof boards may be examined 

while he is in the attic. If light can be seen between these boards the roof is unsound. Evidence of a leaking roof will be indicated 

by loose plaster or peeling or stained paint and wall paper. Areas of the roof where flashing occurs, such as around the chimney, 

are frequent origins of roof leaks. It is essential that the leak be found and repaired, not only to prevent the entrance of moisture 

into the building, but also to prevent the loosening of the plaster, rotting of timbers, and extension of damage to the remainder of 

the house.

Gutters and rain leaders should be placed around the entire building to insure proper drainage of water. This will lessen the 

possibility of seepage of water through siding and window frames, and entrance of water into the cellar or basement. Lack of or 

leaking gutters may result in rotting of the siding or erosion of the exposed portion of the cellar or basement walls. This situation 

commonly exists where the mortar between bricks or concrete blocks in foundation walls is found to be heavily eroded. Gutters 

should be free from dirt and leaves.

The exterior siding should be in sound, weathertight condition. Peeled or worn paint on wood siding will expose the bare wood to
the elements and result in splitting and warping of siding. This condition will eventually lead to the entrance of rain water with 

resultant rotting of the sheathing and studs as well as inside dampness and falling plaster. Sound and painted siding will prevent 

major repairs and expenses in the future. This condition will often be particularly prevalent on the north face of the structure.

Roof and chimneys should be inspected for tilting, missing bricks, deterioration of flashing, and pointing of chimney bricks. In

addition, roof covering should be checked for broken spots and missing shingles or tiles. Roof doors should be metal clad, selfclosing, tight fitting, and unlockable. The roof should also be examined for weather-tightness and broken TV antennas.

Porches should be carefully examined for weakened treads, missing or cracked boards, holes, and holes covered with tin plates, 

railing rigidity, missing posts, handrail rigidity, condition of the columns that support the porch roof, and the condition of the 

porch roof itself. The open section beneath the porch should be inspected for broken lattice-work. Check under the porch for 

accumulation of dirt and debris that can offer a harborage for vermin and rodents.

Loose plaster and missing or peeling wallpaper or paint should be noted. Bugs and cockroaches eat the paste from the wallpaper 

while leaving behind loose paper.

The basic parts of a stairway that a housing inspector should be able to identify correctly are the following:

A Riser 

B Tread 

C Nosing 

D Handrail 

E Balustrade and Balusters, the Vertical Members that Support the Handrail, and 

F The Soffit, Underpart of the Stairway.

In the examination of a stairway (be careful to turn the light on) initially check the underside, if visible, to see if it is intact. Then 

proceed slowly up the stairs placing full weight on each tread and checking for loose, wobbling, or uneven treads and risers. 

Regardless of the size of the treads or risers they should all be of uniform size. For all stairs that rise 3 or more feet, a handrail 

should be present and in a sound and rigid condition.

Any fireplace should conform to the requirements of the local code. An unused fireplace that has its opening covered with 

wallpaper or other material should have a solid seal behind the paper. Operable fireplaces should have a workable damper and a 

fire screen, and should be clean.

Garages and accessory structures should be inspected in the same manner as the main building.

Sidewalks and driveways, whether constructed of flagstone, concrete, or asphalt, should be checked for creaking, buckling, and 

other conditions dangerous to pedestrian travel.

Stone, brick, or concrete steps should be inspected for cracks, deterioration, and pointing.

Fences should be in a sound condition and painted. Fire escapes should be checked for paint condition, loose or broken treads and 

rails, proper operating condition, and proper connection to the house.

V. Noise as an Environmental Stress

People feel comfortable in an environment with a low-level, soothing, steady, unobtrusive level of sound, typical of the natural

undisturbed environment. All of us have experienced the anguish that noise can cause, whether it be noise from a neighbor's 

television, the grinding of truck gears while asleep, the persistent whine of a fan motor, or the sound of children racing down the 

halls. These annoyances experienced in the home are producing public demands for noise control legislation.

Not only is noise disturbing, but studies also indicate that extreme noise can cause deafness and perhaps interfere with other 

bodily functions.
While few existing housing ordinances contain enforceable noise provisions, noise problems must be considered by the building 

inspector because they intimately affect and are affected by his decisions. As a housing inspector, you can help residents by 

suggesting corrective noise measures that can be taken; you can refer them to agencies, if needed, for corrective action; you can 

help them to understand that their noisy environment can place limitations on their behavior, capabilities, and satisfaction with 

their home.

Noise is unwanted sound. Noise can travel through air or through the building structure. The first stage of noise control is the

control of sound at its source. If attempts to quiet the source are not completely successful, then other; more expensive 

corrective measures will be required.

Although a visual examination of a dwelling may detect some sources of noise leaks (see Figure 4-10) such as wide gaps or cracks

at ceiling, floor, or adjoining wall edges, it is usually inadequate since it fails to detect sources of noise leaks hidden from the eye. 

A far more effective test is to be alert for the operation of some noisy device like a vacuum cleaner in a closed room and listen 

near the other side of the wall for any noise leakage. The ear is a reasonably good sensing device. If a noise leak is noticed, the 

partition may be surveyed at critical points with a bright flashlight while an observer looks for light leakage in a darkened room on 

the other side. Detection of any light leakage in the darkened room will signify a noise leak.

Figure 4-10 Transmission Of Airborne Noise

Noise carried as vibration by a building structure is called structure-borne noise. Detecting structure-borne noise caused by the 

operation of mechanical equipment is somewhat more difficult (see Figure 4-11). With noisy equipment in operation, the inspector

can sometimes locate noise leaks or structure-borne noise paths by conducting similar hearing tests along with pressing the ear 

against various room surfaces or using fingertips to sense the vibration of these surfaces.

A Airborne Noise

The sources of airborne noise that cause the most frequent disturbances in the home are audio instruments such as televisions. 

radios. phonographs, or pianos; adults and children speaking loudly, singing, crying and shouting; household appliances such as 

garbage disposals, dishwashers, vacuum cleaners, clothes washers, and dryers; plumbing noises such as pipes knocking, toilets 

flushing, and water running.

The disturbing influences of airborne noise are generally limited to the areas near the noise source. For example, a phonograph 

may cause annoyance in rooms of a neighbor's apartment adjacent to the phonograph but rarely in rooms farther removed unless 

doors or passageways are left open. Sound absorption materials such as carpeting, acoustical tile, drapery, and upholstered 

furniture in the intervening rooms may often provide a significant reduction in the disturbing noise before it reaches rooms where 

quiet is desired.

Under no conditions should sound-absorptive materials be used on the surfaces of walls and ceilings for the sole purpose of 

preventing the transmission of sound as structure-borne noise. To do so would be a complete waste of effort. To illustrate, 

imagine the noise conducted by a wall constructed solely of drapery or acoustical tile attached to studs. The noise level in the

room would be reduced, but sound produced in the room would pass through the wall to adjoining rooms with little, if any, 

reduction in noise level. Sound absorptive materials should be used in and near areas of high noise levels to limit airborne noise 

at the source of the noise and reduce the effects of noise along corridors.

The transmission of noise from one completely enclosed room to an adjoining room separated by a partition wall may be either 

direct transmission through the wall, indirect transmission through other walls, ceilings, and floors common to both rooms, or 

through corridors adjacent to such rooms.

In some older wood frame houses, the open troughs between studs and joists are efficient sound transmission paths. This noise 

transmission by indirect paths is known as "flanking transmission" (see Figure 4-10 and 4-11). In addition to the flanking paths, 

there may be noise leaks particularly along the ceiling, floor, and sidewall edges of the wall. In order to obtain the highest sound 

insulation performance, a partition wall must be of airtight construction. Care must be exercised to seal all openings, gaps, holes, 

joints, and penetrations of piping and conduits with a nonsetting caulking compound. Even hairline cracks, particularly at 
adjoining wall, floor. and ceiling edges, transmit a substantially greater amount of noise than would normally be expected on the 

basis of the size of the crack.

It is often helpful to use one sound to drown out another disturbing noise; for example, music on the radio can be used to drown

out the noise of traffic. The use of sound to drown out noise is particularly useful in masking noises that occur infrequently, such 

as accelerating or braking vehicles, periodic mechanical equipment noise, barking dogs, laughter, or shouting.

B Structure-Borne Noise

Figure 4-11. Flanking Transmission Of Impact And Structure-borne Noise

Structure-borne noise occurs when wall, floor, or other building elements are set into vibration by direct contact with vibrating 

sources such as me chanical equipment or domestic appliances. A small, vibrating pipe firmly attached to a plywood or gypsum 

wall panel will amplify the vibration noise. An illustration of this amplification of structure borne noise is provided by the sound 

board of a piano. The major sources of structure-borne noise are the impact of walking on wood floors or of slamming doors, 

plumbing system noises, heating and air-conditioning system noises, noise from mechanical equipment or appliances, and 

vibration from sources outside the building. If the vibration is severe enough, it may have adverse effects not only on tile 

occupants of a building but also on the building structure.

Household appliances such as refrigerators, washing machines, sewing machines, clothes dryers, televisions, and pianos should be

vibration isolated from the floor by means of rubber mounts placed under them if disturbing structure-borne noise is to be 

avoided. Residents should also be cautioned against locating these noise sources along party walls and in particular against 

mounting these appliances and kitchen cabinets 'directly on party walls so that the walls act as sounding boards in adjoining 

apartments. Window air-conditioners should be completely vibration isolated from the surrounding window frame by rubber 

gaskets and padding. The importance of isolating a vibrating source from the structure in the control of equipment noise cannot 

be overemphasized.

Another source of disturbing structure-borne noise is squeaking of wood floors. Some squeaks can be eliminated by lubricating 

the tongues of wood floor boards with mineral oil applied sparingly to the openings between adjacent boards. Loose finish flooring 

may be securely fastened to subflooring by surface nailing into the subfloor and preferably the joists. Ring-type nails or sawtooth 

staples properly spaced should be used in nailing finish flooring to subflooring. In an exposed joist structure, where finish flooring 

is warped, driving screws up through the subfloor and into the finish floor will be effective in drawing the layers of flooring tightly 

together to reduce noise.

Of course, noise caused by the impact of walking or scraping can be substantially reduced by the use of carpets. In the case of 

door slams, the impact noise may be eliminated by the use of door closers or rubber bumpers.

The noisy hammering of a plumbing system is usually caused by the sudden interruption of water flow, for example, by a quick 

closing or opening of a tap.

Air chambers can be built into the plumbing system to reduce water hammer. The air pockets, rubber inserts, or spring elements 

in air chambers act to reduce noise. Air chambers are explained in Chapter 6.

Defective, loose, or worn valve stems create intense chattering of the plumbing system. The defective device can frequently be 

found without difficulty, since immediate use of the device causes the vibration, which generally occurs at some low-flowvelocity 

setting and diminishes or disappears at a higher flow setting. For example, if a chattering noise occurs when a particular faucet or 

tap is opened partially and diminishes when fully opened, the faucet more than likely has some loose or defective parts and 

should be repaired.

Noise can be a very complex problem. The housing inspector is not expected to be an acoustics expert. Nor is he expected to be 

able to analyze and solve the noise problems that an acoustics consultant would normally handle. He can, however, help teach the

public that the annoyances and stress caused by noise can be partially alleviated by a simple awareness of common noise 

problems found in many residences.
Although the housing inspector is not an expert in the fields of zoning, plumbing, building, and electrical systems, he should- be 

familiar with the applicable code in each of the respective fields. Familiarization with these codes will better enable him to 

recognize violations.

Table of Contents | Acknowledgements | Foreword | Chapter1 | Chapter 2

Chapter 3 | Chapter 4 | Chapter 5 | Chapter 6 | Chapter 7

Chapter 8 | Chapter 9 | Chapter 10 | Chapter 11

 

 

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