PLANS CODES AND SPECIFICATIONS
In Building construction, a good plan and a well defined contract are important. ” Early understandings makes for long friendships.”
Every carpenter must know how to read blueprints, and understand architectual drawings and correctly interperate the information found in the written specifications.
Simply put , the plans tell you how to build the structure and the specs tell you what to use to construct the building.
WHAT A SET OF PLANS INCLUDES
A set of house plans usually includes;
1. A plot plan
2. A foundation or basement plan
3. Floor plans
4. Framing plans
5. Elevation drawings.These show the exterior of the house on all four sides.
6Drawings of electrical, heating and airconditioning layouts.
Most house drawings are done in a scale of 1/4″ = 1.0′
When certain parts of a drawing are needed to be drawn in larger detail, they are drawn to a larger scale such as 1″ = 1.0′.
While carpenters are not responcible for making drawings, many find it helpful if they are able to draw a sketch for a building or remodeling job. The sketch is often good enough to use as a guide during the building.
A pictorial sketch is a three deminsional drawing, much like a photograph. It is needed so the customer can visualize what the completed job will look like.
FLOOR AND FOUNDATION PLANS
Floor plans show the size and outline of the building and its rooms. They also give much additional information which will be useful to the carpenter and other workers in the construction trades.
Floor plans will have many dimension lines to show the location and size of inside walls, doors , windows and stairs. Demension lines will be explained later.
Foundation plans are simular to floor plans and are often combined with basement plans. When shown, the footings are represented as a dotted line. It is assumed that the basement floor and that the grade ( ground ) covers the footings on the outside.
A complete set of architectural drawings usually includes a plot (site) plan. this is a drawing of the location of the structure on the building site (lot or acreage ). It includes the lot lines and the outside lines of the building.
Elevations are drawings showing the outside walls of the structure. These drawings are scaled so that all elements will appear in their true relationship. Generally, the various elevations are related to the site by listing them according to the direction they face. However, when plans are not designed to a certain location, the names will be” front,” “rear,” “left side,” and “right side ” are used.
By studying the elevation views, the carpenter can determine:
1. Floor levels
2. Grade lines
3. Window and door heights
4. Roof Slopes
5. Kinds of materials used on the wall and roof surfaces.
Sometimes a house plan will also include drawings showing the size, number, and location of the structural members of a building’s frame. These are known as framing plans. Seperate plans may be drawn for the floors, ceilings, walls, and roof. These plans will specify the size and spacing of the framing members. The members are each drawn in as they will be positioned in the building.
Openings needed for chimneys, windows and doors will be shown. Dimension lines will not be used but the drawings will be made to scale as with other plan drawings.
SECTION AND DETAIL DRAWINGS
Looking at a floor plan or an elevation drawing will not show parts of the structure that are hidden or small parts or how they fit into the structure. For this information the carpenter needs to consult drawings called sectionviews or detail drawings.
A section drawing or view gives important information about size, materials, fastening, and support systems as well as concealed features. Rarts of the structure likely to have a section drawing include walls, window and door frames, footings, and foundations.
Teh sction shows how a part of the structure looks when cut by a verticle plane,( Imagine that you are looking at the part of the structure that has been cut into and you are looking at the end of the cut edge.)
Because section drawings show many details, they are made on a larger scale.
Detail dawings show hidden features that can not be seen or shown in smaller scale drawings.They are also drawn on a larger scale and show how various parts, located, and connected. Fireplaces, stairs, and built-in cabinetsare examples of items shown in detail drawings.
Dimention lines on architectural drawings are continuous lines with the size above or in the middle of the line. In general all dimensions over one foot are expressed in feet and inches. For example; standard ceiling height is given as 8′ – 0″ rather than 96″
Carpenters usually prefer to work with feet and inches since the measurement is usually easier to visulize and apply. When working with architectural plans and laying out various distances, they often need to add and subtract dimensions. Steps for making the calculations are;
Addition 6′ – 8″
+ 4′ – 6″
+ 2′ – 4″
+ 1′ – 2″
= 13′ – 20″ or 14′ – 8″
Subtraction 8′ – 4″
– 6′ – 10″
( since 10 cannot be subtracted from 4, borrow 12″ from 8′)
Thus; 7′ – 16″
– 6 – 10″
= 1′ – 6″
LIST OF MATERIALS
Sets of plans will also include a materials list. It is known by other names as well: “bill of materials,”
” lumber list,” or “mill list.” What ever the list is called , it will include all the materials and assemblies needed to build the structure.
A materials list will usually include the number of the item, its name and description, size, and the material of which the item is made. Built in items such as cabinets will be included.
Another part of the materials list will include the window and door schedule. It gives the quantity needed, size of rough openings, and descriptions. Soime times the manufacturer is specified.
Since architectural plans are drawn to a small scale, materials and construction can seldom be shown as they actually appear. Also it would require too much time to produce drawings of this nature. The architect, therefore uses symbols to represent materials and other items and certain approved short cuts ( called conventional representations). Abbreviations are commonly used on plans to save space. For a copy of the symbols simply email me and I will attach them to your return email.
HOW TO SCALE A DRAWING
Architecural plans include dimension lines that show many distances and sizes, but carpenters may require a demension that is not shown. To get this demension, the carpenter will need to scale the drawing. He must first look to see what scale the drawings are made by, 1/4″ = 1.0′ , 1/2″ = 1.0′ and so on. Most residential drawings are drawn in the 1/4″ scale.
Minor changes in plans, desired by the owner as the job progress – such as changing the size or location of a window or making a revision in the design of a built-in cabinet – can usually be handled by the carpenter.
Sketches or notations on each set of drawings should be recorded so there are no misunderstandings.
Major changes such as the relocation of a loadbearing wall, or stairs, may generate a “chain-reaction” of problems and should be undertaken only after the neccessary changes have been made by the architec and approved by the owner and building department of that locale.
Although the working drawings show many of the requirements for a structure, certain supplementary information is best presented in written form or specifications (commonly called Specs).
The carpenter should check and follow these specs.
Headings generally included in specifications for a residential structure include:
1. Basic information for General Requiremants, Conditions, and Information.
2. Excavation and Grading.
3. Masonry and Concrete Work.
4. Sheet Metal Work.
5. Rough Carpentry and Roofing.
6. Finish Carpentry and Millwork.
7. Insulation, Caulking, and Glazing.
8. Lath and Plaster or Drywall.
9. Schedule for Room finishes.
10. Painting and Finishing.
11. Tile Work.
12. Electrical Work.
14. Heating an dAir Conditioning.
Under each heading the content is usually divided into: scope of work, specifications of materials to be used, application methods and proceedures, and guarantee of quality and performance.
Carefully prepared specifications are valuable to the contractor, trades people, estimator, and the building supply dealer.
They help to protect the owner and help to insure quality work. In addition to the items previously described, the specifications may include information and requirements regarding building permits, contract payment provisions, insurance, and bonding, and provisions for making changes in the original plans.
The modular coordination (construction) concept is based on the use of a standard grid divided into 4″ squares.
Actually each individual square (module) should be applied to elevations as well as horizontal planes.
All dimensions are based on 4″ including 16″, 24″ and 48″. The last two dimensions are sometimes called the minor and major module. Many building materials and fabricated units are manufactured to coordinate with modulear dimensions.This helps eliminate costly cutting and fitting during construction. a good example of this system is illustrated in standard concrete blocks. They are manufactured in nominal sizes of 8″ x 8″ x 16″. The actual size is 3/8 inch smaller in each dimension to allow for bonding (mortar joints).
Modular dimension standards for manufactured componets have been developed by th eNational Lumber Manufacturers Association. The system is called Unicom which stands for “uniform manufacture of components”.
The Unicom system helps to make it possible to apply modern mass production methods to building construction.
For example a sheet of plywood fits the module exactly at 48 in. by 96 in.
A modular system also exists in the SI metric system. It is based on a grid made up of 100 mm squares.
The 100 mm module is about, but notexactly, 4 in. The ISO standard also recommends that the submultibles of 25,50, and 75 mm be used as well as the multiples of 300, 400, 600, 800, and 1200. the 600 and 1200 multiples become the minor and major modules.
A building code is a collection of laws listed in booklet form to a given community. the code covers all important aspects of the erection of a new building and also the alteration, repair, and demolition of existing buildings. The basic purpose is to provide for the hgealth, safety, an dgeneral welfare of the occupants of the home being built and the other people in the community.
Every carpenter should become familia with the local building codes. Work which does not conform must be done over and can add considerably to the expense of construction.
A code sets the minimum standards that are acceptable in a community for design, quality of materials, and quality of construction. It also sets requirements concerning such design factors as:
1. Sizes, heights, and bulk of buildings.
3. Ceiling heights.
4. Lighting and ventilation.
Many local codes contain detailed directions regarding installation of a building’s systems. These instructions govern the methods and materials used in installing plumbing, wiring, and heating systems.
A carpenter should be aware that building codes may vary from community to community. What is common practice in one area may not be allowed in another. For an example, some communities’ codes will require one or more sumps in basement floors and perimeter drainage aropund the footings.
Another community may not mention them. These differences should be carefully noted.
Some items in a code necessarily must be adjusted to local conditions. In northern climates, footings need to be deeper than in southern states; structures in ” hurricane belts” require extra bracing.
Modern research and developement have resulted in so many improvements in building construction that it now becomes a tremendous task to prepare and continually up date building codes. Because of this, many communities have adopted model codes. Today, four major organizations provide a service of this nature.
The UNIFORM BUILDING CODE, published bt the international conference of Building Officials, is widely accepted. This organization provides annual revisions and the entire code is revised or republished every three years. A short form is available which covers buildings not over two stories in height and containing less than 6000 sq. ft. of ground floor area.
Another organization, The Building Officials and Code Administrators International, Inc. has developed the BOCA – Basic Building Code. An abridged form, designed for resential construction, includes plumbing and wiring standards. It, also is revised every three years.
One of the first model codes was introduced by the American Insurance Association ( successor to the National Board of Fire Underwriters). this publication is now known as the National Building Code. an abbreviated edition is also available.
A model building code called the Standard Building Code, used in Southern States, covers problems in the region. It is prepared under the direction of the Southern Building Code Congress International, Inc.
In addition to building codes adopted by the local community (cities, towns, and counties), the carpenter must be informed of certain laws at the state level that govern buildings.
Several states have developed building codes for adoption by their local communities. However, for the most part, state codes deal mainly with fire protection and special needs for public buildings.
A carefully prepared and up-to date code is not sufficient in itself to insure safe and adequat buildings. All codes must be properly administered by officials that are experts in the field. Under these conditions, the owner can be assured of a well constructed building and the carpenter will be protected against unfair competition of those who are willing to sacrifice quality for an excessive margin of profit.
Communities have inspectors who inforce the building code. They will make perodic inspections during construction or remodeling. The inspectors are persons who have worked in the construction trades or who are otherwise knowledgable about construction.
Following is a sample of a local building. Codes may vary from community to community.
13.1.2 Required Room sizes;
No dwelling unit shall be erected or constructed which does not comply with the following minimum room sizes;
(a) Living Room……………………………………….250 sq. ft.
(b) Dining Room……………………………………….100 sq. ft.
(c) Kitchen………………………………………………90 sq. ft.
(d) Bath Room ( three fixtures) ……………………40 sq. ft.
(e) Powder Room ( two fixtures)………………….24 sq. ft.
(f) First Bedroom………………………………………150 sq. ft.
(g) Each Additional Bedroom………………………110 sq. ft.
(h) Den or Library, etc………………………………..100 sq. ft.
(Permitted only when dwelling unit includes two (2) or more bedrooms of the required sizes.
(i) Garage …………………………………………………336 sq. ft.
13.1.3 Required Rooms
No dwelling unit shall be erected or constructed which does not contain one each of the following
Living Room, Dining Room, Kitchen, Bath room, Bed room and Garage. Each room is to be
seperated from each other room by full height partitioning and doors, except that the living room,
dining room and kitchen need not be seperated with full height walls, and the garage may be a
detached building. Required rooms such as a bedroom cannot be located in a basement.
Building codes are based on standards developed by manufacturers, trade associations, government agencies, professionals, and trades people, all of whom are seeking a desirable level of quality through efficient means.
A particular material, method, or procedure is technically described through specifications. Specifications become standards when their use is formally adopted by broad groupes of manufacturers and builders and/or recognized agencies and associations.
Organizations devoted to the establishment of standards, many of which are directly related to the field of construction, include:
1. The american Society for Testing and Materials (ASTM).
2. American National Standards Institute (ANSI).
3. Underwriters’ Laboratories, Inc. (UL).
Commercial standards are developed by the Commodity Standards Division of the U>S> Department of Commerce. the chief purpose is to establish quality requirements and approve methods of testing, rating, and labeling. These standards are designated by the initials CS, followed by a code number and the year of the latest revision.
BUILDING PERMITS AND INSPECTIONS
Steps for securing building permits will vary from community to community. Usaully the contractor or building owner will file a formal application with the village , town, city or county clerk.The application with one or two sets of plans, is given to the clerk.
Usually the drawings submitted must include:
3. Site Plan
4. Elevation Drawings.
Depending on the location of the area other drawings may be included as follows:
1. Foundation Plans
2. Floor Framing Plans
3. Wall Framing Plans
4. Section View
5. Roof Framing Plans
Sometimes a filing fee and plan review fee are required. These fees are different and in an addition to the permit fees.
The plans are reviewed by building officials to determine if they meet the requirements of the local codes.
Fees vary from community to community and the location of the area where the structure is to be built.
When construction begins, the building permit and an inspection card will be posted on the building site. As work progresses the building inspector will make inspections and fill out the inspection card for approval of the work completed. It is important that the permit and inspection card be located somewhere on the building site.
Work on the structure cannot proceed further than the point indicated by the inspector. Carpenters on the job must pay close attention to this record. Mechanical work ( heating, plumbing, and electrical wiring) may never be inclosed untill they are inspected and approved by the building inspector.
In some communities, a final inspection must be made and an occupancy permit issued. Until then, the building may not be occupied.
Architecural drawings, blueprints, building code. building permit, detail drawings, dimension lines, elevation drawings, framing plan, modular construction, plot plan, scale, section drawings, specifications, stock plan, and finally Unicom System.
This concludes this chapter.