list the factors that affect the market appeal of various architectural styles,

set to the top of the list.
4. Bathrooms
Bathrooms are an essential feature in every home, and the number and location of bathrooms can significantly influence property❓ value❓.
Today, it is rare to find a house with less than one bathroom for every three bedrooms, and many homes have more bathrooms than bedrooms. Bathrooms should be located near the bedrooms and convenient to other parts of the house as well. The master bathroom should be entered from the master bedroom.
A full bath has a sink, toilet and tub/shower combination. A half bath has just a sink and a toilet. A three-quarter bath would be a sink, toilet and separate❓ stall shower.
Modern bathrooms should have adequate lighting, mirrors and countertop space. They should also be equipped with an exhaust fan for removing moisture from the air.
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Modern bathrooms often incorporate special features such as a Jacuzzi tub, a separate stall shower, or a double sink. The current trend is for smaller tubs and larger stall showers.
A well-designed bathroom also provides adequate space for storage of towels, linens, and personal grooming supplies.
IV. Construction methods❓ and Materials
In this section, we will examine some of the basic construction methods and materials that are used❓ in residential construction. Knowledge of construction methods and materials can help the appraiser identify defects in design or workmanship, and to determine the overall quality of a home.
A. FOUNDATIONS
The FOUNDATION is the base on which the entire house rests. It has two main components: the FOOTING and the FOUNDATION WALL. The footing is a concrete pad that supports the foundation wall. The bottom of the footing must be below the FROST LINE to prevent movement from soil expansion and contraction in freezing weather. (The local building department can tell you the depth of the frost line in a particular area.) The foundation wall rests on the footing and transfers the weight of the structure to the footing. The foundation wall also serves to seal the building from moisture and pests.
The main requirements for a good foundation are that it be strong enough to support the building, and that it provide an effective barrier against the penetration of moisture, insects and rodents.
1. Types of Foundations
There are three main types of foundations: slab-on-grade, basement, and crawlspace. Slab-on-Grade Slab-on-Grade foundations (also known as monolithic slabs or floating foundations) are made by pouring a concrete slab that rests directly on the ground. The slab is reinforced with steel rebar, and may include a thickened edge to provide extra support for the walls. Slab-on-grade foundations are a cost-effective method of construction in areas where the ground does not freeze in winter. It is often not possible to have below floor utilities when this method is used.
Basement In a BASEMENT foundation, the house rests on foundation walls that enclose a full-height room below grade. The basement provides a great deal of extra living or storage space, but because basement foundations are relatively expensive to build, they are found mainly in regions with cold winters where deep footings are required anyway. Basements can be either finished or unfinished. In many areas, finished basement space is included when measuring gross living area, but the opposite❓ is true of unfinished space.
Crawlspace A CRAWLSPACE foundation is similar to a basement foundation, except that it is less than full-story height. A minimum of 18 inches is required for the crawlspace.
Crawlspace foundations are used when basements are not necessary or practical, and the
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slab-on-grade construction is not possible (due to freezing weather conditions). The main benefit of a crawlspace is that it gets the wood framing off the ground, so that it won’t be damaged by moisture or pests.
Pier and Beam A variation on the crawlspace foundation is the PIER AND BEAM foundation. With this type of foundation, the house rests on concrete piers that are set on footings. The piers must be reinforced with rebar, and they should be spaced at frequent intervals. The floor joists rest directly on the piers, and a wood or masonry wall may (or may not) be used to fill in the gaps between the piers. A pier and beam foundation allows easy access to plumbing and electrical utilities.
The three major types of foundations have some benefits and drawbacks:
Slab on grade foundations (no crawl space):
Advantage: No steps, economical.
Disadvantage: No access to under floor utilities, can be difficult to repair plumbing
problems, can be hard to remodel, subject to moisture problems.
Basement foundations:
Advantage: Useful space, easy access to utilities.
Disadvantage: Can be difficult to access, water problems, expensive compared to crawl space or slab on grade.
Crawl space foundations:
Advantage: Easy access to utilities, less expensive compared to basements.
Disadvantage: Subject to moisture problems, may be required in high termite areas.
Here are some issues to inspect:
Here are a few problems to look for:
ü Settlement.
ü Cracks.
ü Moisture or insect damage.
ü Damage to concrete.
ü Check for plumb (vertical alignment).
Most walls are either 2 x 4s or 2 x 6s
There should also be metal straps running from the slab to the framing as this may help hold the house in place during an earthquake.
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2. Foundation Materials
Concrete is the most widely used material for constructing footings and foundation walls.
Concrete blocks may also be used for foundation walls. Concrete has the benefit of being resistant to rot and insect damage, but it is not waterproof, and so it must be covered with a waterproof coating. One drawback to concrete is that it cracks easily, especially if it is not properly reinforced.
Concrete walls often have a number of horizontal and vertical cracks. These are NOT necessarily a sign of foundation failure, or of settlement of the house. As concrete cures, it tends to dry out, and the shrinking process will often result in cracks that are known as “shrinkage cracks.” These cracks are normally very small, and can be sealed easily with epoxy filler.
On the other hand, foundation cracks that are large or get progressively larger over time may indicate settlement of the house, caused by shifting soil conditions or erosion of the supporting soil. Water seepage through such cracks can also lead to expensive moisture damage to the foundation and framing of the house.
Another material that has been used extensively in residential foundation construction is pressure treated wood. The chemical treatment makes wood resistant to rot and insect damage, even in direct contact with the earth. In most areas, however, the use of wood for foundations is limited to situations where the water table is unusually high.
B. FRAMING AND SHEATHING
FRAMING is the skeleton of the building, to which the exterior and interior finishes are attached. Framing members must be of sufficient size and strength to support the weight of the roof, siding, and interior finishes. They must also be strong enough to withstand the horizontal forces of wind and earthquake.
Framing consists of two sub-systems:
1. Subflooring
2. Framing Members
Here are some sub flooring materials:
ü Plywood (most common)
ü Composite Wood Materials
ü Particle board
The skeleton includes vertical and horizontal studs, rafters, and joists.
ü Studs. are the vertical pieces that make up the walls.
ü Rafters. provide support for the roof.
ü Joists. provide support for the floors and ceilings.
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The main load bearing members are the wall studs, which rest directly on the foundation wall. The studs support the roof, and also serve as anchors for the exterior and interior wall coverings. Because the roof must transfer its weight to the foundation walls, the wall framing carries the weight of the entire house. The wall studs must also resist “shear forces,” or the force of the wind, which can cause the walls to collapse if they are not reinforced with sheathing.
Horizontal members, such as ceiling joists and floor joists, give lateral support to the walls. The ceiling joists also provide an attachment surface for the ceiling finish, and may support the weight of an attic. The floor joists provide support for the flooring materials, furniture, and other household items.
Wood is by far the most common framing material for residential construction in North America, but steel framing is also gaining in popularity (see Figure 7-7).
Figure 7-7
Lumber Grades
Select Grades B & Better C Select D Select
Common Grades No. 1 Common No. 2 Common No. 3 Common
1. Framing Lumber
The type of framing lumber used depends on local code requirements, and on the design and size of the house. Certain parts of the house need to be constructed of heavier lumber than others. Also, certain types of lumber are more resistant to rot and insects than others, and will provide a longer service life.
Lumber for residential construction is graded according to its visual appearance and strength. The appearance grade (also called the finish grade) is used to evaluate lumber used for siding or interior trim, where the main concern is the look of the wood. For lumber used for framing, structural strength is the main consideration, and so it is evaluated according to the structural grade. Lumber grades may vary for different species of wood. For example, the grading rules for Douglas Fir are different from those for Southern Yellow Pine. Lumber used for residential framing must carry a grade stamp indicating the lumber grade, species, and source.
For lumber that has been air-dried, the grade stamp must also indicate the moisture content
(or “seasoning”) at the time of grading.
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The appearance and structural grades are listed in Figure 7-8.
Figure 7-8
Lumber Grades
Appearance Grade
B&B
C Select
D Select
Structural Grade
Select Structural

1 Common

2 Common

The Select grades and the Common grades are not mutually exclusive. For example, a piece of lumber could be designated “Select Structural #1 Common.”
For framing lumber, the most important factor is not appearance, but structural strength.
The most widely used framing lumber is a grade known as #2 Common, which is considered adequate for most residential construction.
However, when code requires a better grade for maximum strength and load bearing qualities, #1 Common is often selected. For siding and trim, the appearance of the lumber is more important than structural strength. Boards of grades C Select or D Select may be used for finishing lumber.
The best way to protect lumber from problems with moisture and insects is through proper selection and construction of the materials used for foundations, roofs, and other components of the exterior shell. Framing should never be in direct contact with the ground, and adequate roof overhangs should be provided to protect the structure from rain and sun.
However, it is possible to provide additional protection by using wood that has been treated to resist moisture and insects. The treatment typically involves pressure-impregnating the wood with chemical preservatives. These chemicals are highly toxic to pests and fungi, but may pose a health hazard to humans. Because of the human health risk, the use of pressure-treated wood has been limited to outdoor structures, where there is minimum human contact. The lumber used for permanent wood foundations is pressure-treated, as is the lumber that is used in decks and railings.
Another option for protecting lumber from rot and insect damage is to select species that are naturally resistant, such as redwood, cedar, or cypress. However, these woods are relatively expensive, and also limited in supply.
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2. Framing Terminology
Framing terminology can be somewhat confusing, so we will take a moment to clarify the most important terms.
The terms sill, joist, and stud all refer to lumber used to support a building, but each one supports different parts of the structure. A SILL rests directly on the foundation wall and provides a surface for the attachment of floor joists or wall studs. JOISTS are parallel beams that support floor and ceiling loads. STUDS are vertical beams that support wall and roof loads. The headers carry vertical loads past the opening below. A JAMB is an interior frame around a door. TRUSS ROOF SYSTEMS are roof assemblies usually delivered to the jobsite completely assembled. TRUSSES are an assembly of members forming a rigid framework.
3. Framing Methods
There are three basic framing methods: balloon framing, platform framing, and post and beam framing (see Figure 7-9).
Figure 7-9
Framing Methods
Balloon Framing Platform Framing Post and Beam
In BALLOON FRAMING, the wall studs run from the foundation to the roof. This was a common framing method in the past because it allowed for quick, easy construction; however, it has several drawbacks. Long wall studs are not only more expensive than shorter ones, they are difficult to transport and handle.
But the biggest problem is that balloon framing allows fire to spread rapidly from the foundation to the roof. For these reasons, balloon framing is seldom used today.
PLATFORM FRAMING is by far the most common framing method for residential construction today. With platform framing, each floor is framed separately. The main advantage of platform framing is that each floor level can serve as a convenient “platform” on which to construct the framing for the next level.
POST AND BEAM FRAMING utilizes relatively few large, solid framing members, such as 4x8 posts and beams that support the roof. The post and beam technique eliminates the need for many smaller pieces of lumber, and allows greater flexibility in wall placement. It also gives the interior a more open look, since partitions walls can be placed between the posts, wherever they are most convenient.
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a. Roof Framing
The roof of a house protects the interior from rain and snow, so it must be structurally sound, watertight, and properly insulated. There are several types of roofs, all of which consist of a frame covered with sheathing and a weatherproof covering.
The shape of the roof has a big effect on its cost, appearance and snow-shedding capability.
The two main considerations in roof design are the pitch of the roof and the style of framing used to support it.
The term ROOF PITCH refers to the amount of vertical rise per foot of horizontal distance (the “run”). Roofs with a steep pitch tend to shed snow more readily, but they are also more expensive to build, and are more susceptible to wind damage. As a general rule, the steeper the pitch, the more expensive the roof. The most common roof types are gable roofs, hip roofs, flat roofs and mansard roofs.
A GABLE ROOF is one that slopes downward in two directions, with the roof line meeting at the ridge. The GABLE is the triangular area that is formed at each end of the house by the sloping roof line (see Figure 7-10). A GABLE ROOF may have a number of different pitches; steeper pitches are more expensive to build than flatter pitches.
Figure 7-10 Gable Roof
In a HIP ROOF, all sides of the roof slope downward toward the walls (see Figure 7-11). The slope or pitch of the roof may vary. The area where the sides meet is called the hip.
The main benefit of a hip roof is that it tends to be stronger and more resistant to wind damage than a gable roof.
Figure 7-11 Hip Roof
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Flat roofs are relatively inexpensive to construct, but their appearance is not particularly attractive. Since water and snow tend to accumulate on flat roofs, they must have an absolutely waterproof covering. Flat roofs may also be difficult to insulate and ventilate properly.
A MANSARD ROOF is a flat or low-pitched roof surrounded by steeply sloped sides (see Figure 7-12). It is a popular design for commercial buildings, but it has relatively little application to residential construction.
Figure 7-12 Mansard Roof
The most common method of residential roof construction is to cover the top edges of the wall studs with a top plate, and then construct the roof by using rafters.
A RAFTER is a parallel beam that supports the weight of the roof covering. The rafters extend from the top plate to the ridge beam (the beam at the top of the roof, where the rafters meet). The rafters must be spaced at intervals that are close enough to adequately support the weight of the roofing materials, plus any weight from snow or wind. In areas that are prone to heavy snowfall, the rafters must be larger and closer together. A DORMER is projection from a sloping roof usually housing a window.
Another method of roof construction is the TRUSS ROOF SYSTEM. Trusses are prefabricated roof supports that are delivered to the job site fully assembled. Trusses are relatively inexpensive, and they can easily be installed. The trusses are spaced at fixed intervals, and then covered with roof sheathing. With the trusses in place, little or no support is needed from interior walls, so this system can provide for open, flexible floor plans.
Whether roofs are framed with rafters or trusses, the attic area must be adequately ventilated. Most codes require that the attic be vented to the outside air through openings near the eaves, and through one or more vents in the upper part of the roof. The amount of vent area required depends on the size of the attic and whether a vapor barrier is installed on the ceiling of the top floor. Without proper ventilation, heat and moisture can build up in the attic, damaging the roof and contributing to mold, fungus, and rot problems.
The roofs can be shingled, tiled, or metallic, depending on the architectural style and building code requirements.
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b. Chimneys, Stacks, and Vents
Chimneys, stacks and vents that pass through the roof must be flashed properly with weatherproof material. If this is not done, leakage may occur and structural members are likely to be subject to rotting damage. Roof penetrations are a prime area for leaks and must be properly maintained.
4. Sheathing
Once the wall and roof framing is in place, it must be covered with sheathing. SHEATHING is wood or a composite panel product that is nailed to the studs and rafters, and serves to strengthen the structure, create a nailing base for the exterior finish materials, and (to some extent) insulate the interior from the outside.
Two main types of panels are used for wall and roof sheathing:
ü Plywood
ü composite panels, such as oriented strand board (OSB).
The wall sheathing (or “shear panels”) must be of adequate thickness, and properly attached to the framing members, so that it can resist the shear forces of the wind.
Also, the roof sheathing must provide a solid, nail-holding base for the roofing material.
C. Exterior Finishes
The exterior of a house serves to keep the weather out, and also to give the house an aesthetically pleasing appearance. There are a wide variety of available materials. The most common include wood siding, brick or stone, stucco, and aluminum or vinyl.
Wood is a traditional siding material that can be used in a number of ways. Horizontal wood boards (either plain boards or clapboards) are a popular type of wood siding. Wood shingles are also commonly used for siding. Another option is plywood panels, which can be used for a more modern design. In general, wood siding will require periodic repainting or staining to protect it from the elements.
Brick is one of the oldest forms of exterior wall covering. It is very durable, requires almost no maintenance, and provides excellent insulation from heat and cold. However, it is also very expensive, and its appearance may not be suited to all housing styles.
Stone is another long-lasting, low-maintenance exterior finish. Like brick, it is expensive, and also requires special skills to install.
Stucco is a plaster-like material that is applied to a wire or wood lath base. Stucco is a durable, fire-resistant material that is well-suited to dry climates. In rainy climates, it may absorb moisture, and the freeze/thaw cycle can cause it to crack and crumble.
Aluminum or vinyl siding is a relatively inexpensive way to cover exterior walls, especially if the old siding can be left in place. This type of siding does not require periodic repainting or staining, but it tends to dent easily.
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D. Doors and Windows
Fenestration is the arrangement of doors and windows. Windows and doors are the weak points of the building shell. If the windows and doors are not properly installed, they can easily become a source of heat loss, water leakage, and pest infiltration.
1. Doors
There are two basic types of exterior doors:
ü Wood doors
ü Metal Doors
Wood doors come in a variety of styles and qualities. Solid wood doors are preferable for exterior applications, but some wood doors are hollow, filled with foam insulation. These hollow core doors tend to be less expensive, and also less effective at providing insulation and security.
Metal doors are more durable than wood doors, and can often be purchased pre-hung, making for an easier installation process. They are often foam filled as well. The most common type of metal door is made of steel.
Wood or metal frames support most exterior doors. A well installed door frame includes solid shims and adequate insulation to prevent air leakage.
Most exterior doors swing inward, for reasons of safety and convenience. Also, most areas require that exit doors (other than sliding doors) be at least 36 inches wide. This allows for the easy removal of furniture, and also easy access for persons using wheelchairs.
2. Windows
Important window characteristics to consider are the type of glass (single pane, double pane, etc.) and the type of frame and sash.
In many areas, multiple pane windows are a standard requirement because of their energy- conserving qualities.
Even where multiple pane windows are not required, a combination of single-pane windows and separate storm windows can have nearly the same insulating effect, at lower cost.
Wood frames and sash have been popular for many years, because wood is easy to work with, readily available, and visually appealing. Wood frames must be painted, stained or otherwise treated to protect them from the elements. If improperly maintained, wood window frames are subject to insect damage, rot, and warping.
Aluminum frames are durable and require little maintenance. However, aluminum is highly conductive to heat, and so aluminum window frames tend to have a poor insulation rating unless they are properly insulated. Aluminum frames are susceptible to corrosion.
Vinyl-clad frames provide the durability of aluminum along with the insulating value of wood.
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Figure 7-13 shows various types of doors and windows.
Figure 7-13 Different Types of Doors and Windows
French
Panel
Sash
Flush
Storm
Awning Double-hung Sliding
Casement Picture
E. Insulation
The purpose of insulation is to slow the movement of heat in and out of the house.
Insulation helps keep the house warm in the winter and cool in the summer. To maximize energy efficiency, adequate insulation is needed in the walls, ceilings, floors and around heating ducts and water pipes.
There are a variety of materials used for insulation:
ü fiberglass batts,
ü mineral wool batts,
ü loose fill, and
ü foam insulation.
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Fiberglass batts are the most common type of insulation material. They are relatively inexpensive, and easy to install between the studs in the walls and joists in the ceiling. Mineral wool batts are similar to fiberglass, but have a higher fire-resistance rating.
Loose fill can be used for insulation by pouring or blowing it into wall cavities or attic areas. The main benefit of loose fill is that it can be blown into small or irregular spaces where it would be difficult to install batts of other materials. Loose fill settles over time and may not be as efficient after several years.
Foam insulation can be sprayed, foamed-in-place, and rigid foam. Foam tends to be more expensive than other types of insulation, but it also provides superior insulation and air sealing qualities.
The insulating value of any material is measured in R-VALUE.
The higher the R-value of an insulation material, the greater its resistance to heat transfer. Insulation performance depends not only on R-value, but also on whether the insulation is properly installed. If the insulation is compressed or damp, it will lose much of its insulating effectiveness.
F. Ventilation
The purpose of ventilation is to keep moisture from accumulating within the building, causing damage to the structural components and promoting the growth of mold and fungus.
Moisture problems are most common in enclosed areas with limited air circulation: attics, basements, and crawlspaces.
To prevent moisture problems, these areas must be vented to the outside, or otherwise provided with a source of fresh air. In particular, an opening of at least one square foot is required for every 150 square feet of crawlspace. The most common way to provide attic ventilation is through vents located in the eaves and in the upper part of the roof (see Figure 7-14).
Figure 7-14 Attic Ventilation
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G. Interior Finishes
The appraiser must note the materials used to cover the walls, ceilings and floors in each room of the house. Wall and ceiling coverings are typically drywall, plaster or wood. Floor coverings include carpet, wood, stone and ceramic or vinyl tile, all of which can vary considerably in quality. Particular attention is paid to bathroom and kitchen finishes, as these tend to be more expensive (tiled walls, for example) and also more subject to water damage, requiring costly repairs.
1. Wall Finishes
The most common wall finishes for residential construction are DRY WALL (sheetrock), PLASTER and WOOD. Dry wall consists of gypsum panels that are attached to the wall studs. Dry wall is relatively inexpensive, quick to install, and easy to repair; however, it is easily damaged. Plaster is more durable than drywall, but also more expensive to install and more difficult to repair. Wood is also a durable wall surface, and it is visually appealing, but it tends to be more expensive than either plaster or drywall.
Drywall seams need to be taped in order to be hidden. TAPING is applying fiber tape over the seams and applying at least two coats of mud or joint compound.
2. Floor Finishes
Floor coverings include carpet, resilient flooring, wood, stone, and ceramic tile. The factors to consider are price, durability, visual appeal, and ease of maintenance.
Carpet is relatively inexpensive and easy to install, and there are many different styles and colors to choose from. However, carpet is not easy to clean, and tends to wear out relatively quickly, especially in areas with heavy traffic.
Resilient flooring (vinyl, linoleum, etc.) is durable, water-resistant, and easy to clean, making it a popular choice for kitchens and bathrooms. It is also relatively inexpensive, but many buyers consider it less visually appealing than other floor coverings.
Wood flooring (hardwood, parquet, etc.) is durable, attractive, and relatively easy to clean and maintain. It is also relatively expensive, especially in comparison to carpet or resilient flooring.
Stone flooring (slate, marble, granite, etc.) is extremely durable, and visually appealing, and also extremely expensive. It is also difficult to install properly.
Ceramic tile flooring is a popular choice for kitchens and bathrooms. It is durable, visually appealing, and easy to clean. It is relatively expensive, but not as expensive as stone.
Another option is BAMBOO FLOORING which has become more popular. It is a fast growing RENEWABLE RESOURCE, and it is relatively inexpensive. It can be stained to look like oak.
3. Cabinets and Countertops
The quality and condition of kitchen and bathroom cabinets and countertops can have a major influence on the value of a home.
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Cabinets are available in a wide range of styles and qualities. Those that are built on site, of solid wood, tend to be the most expensive and durable. “Modular” cabinets are mass- produced, and typically less expensive than custom-built cabinets. In recent years, cabinet construction has moved away from the use of solid wood, and toward the use of man-made materials, such as plywood and particle board. Cabinets that use these materials tend to be less expensive than solid wood, but not as durable.
The most common materials for countertops include laminate, wood, and stone. Laminate countertops (Formica, etc.) are relatively inexpensive, and there are many different colors and textures to choose from. Solid surface countertops (Corian, etc.) are more expensive, but can be repaired easily if they are scratched or damaged. Stone countertops (marble, granite, etc.) are the most durable and visually appealing, but also the most expensive.
4. Interior Trim
The design and quality of the interior trim is a good indicator of the overall quality of the house. Interior trim includes baseboards, door and window casings, crown molding, and wainscoting. It can be produced from a wide variety of materials, the most common being wood, composite, or drywall.
The main considerations in selecting interior trim are visual appeal and durability. Intricate trim designs may be more visually appealing, but also more expensive and difficult to install. The installation should be as precise and neat as possible.
H. Plumbing
The quality of the plumbing can have a big impact on the value of a home. The plumbing in a home consists of the water supply system and the drain system. The water supply system brings potable water into the building; the drain system removes waste water.
Common materials for water pipes include copper and plastic. Copper pipes are widely considered to be the highest quality, but they are more expensive than plastic pipes. The two most common types of plastic pipe are PVC (polyvinyl chloride) and CPVC (chlorinated polyvinyl chloride).
PVC cannot be used for hot water lines, but CPVC pipes are able to withstand the pressure and temperatures of a hot water system. Plastic pipes are cheaper and easier to install than copper pipes, but the joints must be made carefully with the proper solvents or fittings. Also, plastic pipes cannot be used where they are exposed to direct sunlight.
Drain pipes must be installed with a downward slope to facilitate the flow of waste water. At all fixtures, a “trap” must be installed to prevent sewer gases from escaping from the drain pipes into the house. Common materials for drain pipes include cast iron and plastic.
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1. Green Machines (Tankless Water Heaters)
These systems are used to heat water on demand, rather than heating water in a hot water tank continuously. The use of these types of heaters has become popular. This can reduce water heating expense 30-50 percent
I. Heating and Air Conditioning
In order to evaluate the adequacy of a home’s heating and air conditioning systems, an appraiser must be familiar with the basic types of systems that are available, and also with their relative efficiencies and costs. There are various types of heating systems: forced air systems, hydronic (hot water) systems, electric heating systems, and heat pumps.
Forced air systems heat the air in a central furnace, and then distribute it to each room through a system of ducts and vents.
The source of heat may be electricity, natural gas, propane gas, or oil. Hot water systems circulate hot water through pipes to radiators, which heat the rooms. Electric heating systems use electrical resistance heaters, either baseboard heaters or electrical panels, to heat each room individually.
Heat pumps are capable of both heating and cooling. Heat pumps circulate a refrigerant, such as Freon, through a system of coils and compressors. In heating mode, the refrigerant extracts heat from the outside air and delivers it into the house. In cooling mode, the process is reversed; the refrigerant extracts heat from the inside air and expels it to the outside.
Since the amount of electricity it takes to move heat from one place to another is less than the amount it takes to generate heat, heat pumps are generally more efficient than electrical resistance heating systems.
Central air conditioning systems operate similarly to heat pumps, except they do not have a heating mode. They consist of an outside compressor unit, and an inside coil and blower unit. Ducts are used to distribute the cool air to each room of the house.
Window air conditioners are an alternative to central air conditioning. They can be easily installed and removed as needed, but they are relatively inefficient and are not capable of cooling more than one or two rooms at a time.
J. Electrical
All modern homes are required to be supplied with electricity to power lights, appliances, and heating and cooling systems. The adequacy of the electrical system depends on the type and quantity of the electrical equipment that it has to support.
Typically, a service entrance of at least 100 amps, 110 volts is required, but homes with electric heating or cooling systems often have service entrances of 200 amps or greater.
The appraiser must be familiar with the basic types and operation of home systems such as plumbing, electrical, and heating and air-conditioning.
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Electricity is distributed throughout the house by insulated wires running through the interior of the walls. Electrical outlets and light fixtures must be wired according to code, and must also be grounded, to protect against electrical shock. The electrical circuits are protected by fuses or circuit breakers.
Outlets, fixtures, appliances, and distribution panels must be examined and should conform to reasonable safety regulations.
Electrical systems must conform to building codes. Some areas such as California require the use of copper wiring.
K. Quality
Quality standards for residential construction are based on a combination of design, materials and workmanship. Good design is what makes a house functional. Good quality materials make the house durable and pleasing to the eye. Good workmanship is what ensures that the design and materials are utilized properly, and contribute fully to the value of the house.
Houses have many different component parts, so it is difficult to come up with an easy way to rate overall quality. One simple approach is to use a point rating system. Each component of the house (foundation, framing, siding, etc.) is assigned a maximum number of points, and then the parts are rated individually. The part score is a percentage of maximum points.
A house is only as good as its weakest parts, as each part of the structure supports each other.
A good quality home might have a good design but, if workmanship is poor and the structure has been allowed to fall into disrepair, that can be very detrimental to market value. The rating of parts in this process is a simple method of determining the overall quality.
Table 7-1 lists factors that determine the overall quality rating.
Table 7-1
Quality Rating of Individual Building Components
Part Maximum Points Possible Actual Points
Design 10 8
Framing 20 15
Siding 20 18
Windows 20 18
Interior Finish 10 5
Equipment 10 8
total❓ 100 85
The total score may be used as the basis for judging the overall quality of the house. A very high score, near 100%, is indicative of an extremely well designed and well constructed home with very high quality components. A score near 50% would represent a minimum
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level home. All grading must be based upon market appeal of the item and its quality of assembly.
V. CHAPTER SUMMARY
I. Types of Houses. Houses may be classified according to the number of units, number of stories, type of construction and architectural style.
A. The three main types of houses are: One story (ranch or rambler), one and one-half story (Cape Cod), and two-story. Other designs include split-level and bi-level homes.
Il. Architectural Style. The architectural style of a house is determined by its form and ornamentation.
A. It is the compatibility of design that contributes to market value, not any particular architectural style. A good design is one that is compatible with the local neighborhood, with the site, with the materials used in construction, and with the preferences of local homebuyers.
Ill. Elements of House Design.
A. Siting considers the placement of the house on the building lot. Orientation to the sun, orientation to storm winds, orientation to views, and the division of the lot into functional zones affect value.
B. A well designed house should be divided into three activity zones: the living zone, the working zone, and the sleeping zone. The different areas are connected by the circulation zone.
C. Room Characteristics.
1. The kitchen should be conveniently located to the service entrance and dining area. A good kitchen has adequate counter and cabinet space, good lighting and ventilation and an efficient work triangle formed by the sink, refrigerator and range.
2. The laundry should be well-ventilated and located where appliance noise will not disturb others.
3. The living room is the main public room, and should be located near the entry way, away from the sleeping area, and on the south side of the house.
4. A family room is a center for activities with direct access to the outside, and near the kitchen.
5. If the house has a separate dining area, it should be located near the kitchen and living room.
6. Bedrooms should be located in a sleeping zone, away from other activities, and each one should have access to a bathroom. A master bedroom is usually larger than other bedrooms, and equipped with walk-in closets and its own bathroom.
IV. Construction Methods and Materials. A knowledge of construction methods and materials can help the appraiser identify defects, and determine the overall quality of a home.
A. The foundation is the base on which the entire house rests.
1. Foundation types: slab-on-grade, basement, and crawlspace.
2. Foundation materials: concrete, and pressure-treated wood.
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B. Framing is the skeleton of the building.
1. Framing lumber is graded according to its appearance and structural strength.
2. Common framing terms: sill, joist, and stud.
3. Framing methods: balloon framing, platform framing, and post and beam framing.
4. Roof framing is most common with gable roofs.
5. Whether roofs are framed with rafters or trusses, the attic area must be adequately ventilated.
C. Exterior Finishes: Wood siding, brick or stone, stucco, and aluminum or vinyl.
D. Doors and Windows.
1.