Wood-Frame IHouse Construction

267 Pages·2010·9.13 MB·English

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This haiKlbook presents SOUIKI priiKiples for wood-
frame house construction and suggestions for selecting
suitable materials to assist the construction of a good
house. The organization reflects the general progression
of activity in building a wood-frame house, from initial
conception to completed structure. Chapter 1 describes
matters that should be considered or dealt with before
beginning construction. Chapters 2-4 describe steps in
laying the groundwork, framing and closing in, and com-
pleting the shell, which are usually taken one after
another in the order presented. Chapters 5-7 describe
later tasks that can often be done in some order other
than presented. Chapter 8 discusses special topics often
associated with wood-frame construction. Technical notes,
annotated list of suggestions for additional reading, and
glossary are provided.
Keywords: Wood-frame, house, construction, building
materials, building codes, foundations, framing, siding,
rooñng, paints and stains, energy conservation, noise con-
trol, decay, termites, maintenance and repair.
For sale by the Superintendent oí Documents, U.S. Government Printing Office, Washington, D.C. 20402
Wood-Frame House
United States
Department of
Agriculture
Construction
Forest
Service
Agriculture
Handbook 73
Gerald E. Sherwood, PE
U.S. Department of Agriculture, Forest Service, Forest
Products Laboratory, Madison, Wl
Robert 0. Stroh, PhD
National Association of Home Builders, National
Research Center, Washington, DC
Revised September 1989
Acknowledgments
In preparing the handbook, the following individuals
contributed key technical assistance:
• NAHB National Research Center:
Hugh D. Angleton
E. Lee Fisher
Ralph J. Johnson
Carey F. Lively
Donald F. Luebs
R. Christopher Mathis
Richard A. Morris
Ralph Lee Smith
• U.S. Department of Agriculture, Forest Service,
Forest Products Laboratory:
Rodney C. De Groot
William C. Feist
• National Association of Home Builders:
Michael J. Shibley
The following organizations, which formed the steering
conmiittee that guided the work, also gave their full sup-
port and cooperation:
• Canadian Wood Council
• National Association of Home Builders
• National Forest Products Association
• National Lumber & Building Material Dealers
Association
• U.S. Department of Agriculture, Forest Service
• U.S. Department of Housing and Urban Development
This publication reports research involving pesticides. It
does not contain reconmiendations for their use, nor does
it imply that the uses discussed here have been registered.
All uses of pesticides must be registered by appropriate
State and/or Federal agencies before they can be recom-
mended.
CAUTION: Pesticides can be injurious to humans,
domestic animals, desirable plants, and fish or other
wildlife—if they are not handled or applied properly. Use
all pesticides selectively and carefully. Follow
recommended practices for the disposal of surplus
pesticides and pesticide containers.
CONTENTS
Page
Preface. IV Chapter 6—Working inside 165
Introduction v Interior wall framing ( 166 ), Plumbing,
heating, and electrical installation ( 166 ),
Chapter 1—Before construction starts 1 Insulation and vapor retarders ( 167 ),
Interior wall and ceiling ñnishing ( 175 ),
Regulation (2 ), Financial planning (3 ), Wood flooring ( 180 ), Other floor
Site selection (4 ), House design ( 4 ), coverings ( 187 ), Interior doors ( 187 ).
Selecting materials ( 5 ), Labor-saving
techniques ( 6 ), Materials delivery (6 ), Chapter 7—Finishing touches 191
Efficient use of materials ( 6 ), Energy
conservation ( 6 ), Protection of Interior trim ( 192 ), Cabinets and other
materials ( 7 ), Subcontracting (8 ), millwork ( 196 ), Finishes for interior walls,
Schedule of activity (8 ). ceilings, and trim ( 197 ), Finishes for
floors ( 199 ), Finishes for exterior
Chapter 2—Laying the groundwork 11 surfaces ( 200 ), Maintenance of ñnishes ( 208 ).
Site preparation ( 12 ), Excavation and Chapter 8—Special topics 209
footings (13 ), Foundation ( 18 ), Basement
floor and crawl space ( 22 ), Other Protection against decay and termites ( 210 ),
features ( 25 ), Concrete floor slabs Energy conservation ( 215 ), Noise
on ground ( 29 ), Retaining walls ( 32 ). control ( 221 ), Wind, snow, and seismic
loads ( 223 ), All-weather construction ( 227 ),
Chapter 3—Framing and closing in 37 Maintenance and repair ( 228 ).
Recommended nailing practices ( 38 ), Technical notes 233
Floor framing ( 38 ), Stairways ( 50 ),
Floor sheathing ( 61 ), Exterior wall Concrete ( 234 ), Heat flow and
framing ( 62 ), Exterior wall sheathing (65 ), insulation ( 235 ), Lumber grades ( 237 ),
Ceiling and roof framing ( 72 ), Roof Design values for visually graded structural
sheathing ( 83 ), Roof coverings ( 87 ), lumber ( 238 ), Plywood markings ( 238 ),
Skylights ( 94 ). Finishing pressure-treated wood ( 241 ), Nailing
schedules ( 241 ), Square comers (241 ).
Chapter 4—Completing the shell 99
Selected bibliography 245
Flashing and other sheet-metal work ( 100 ),
Attic ventilation (105 ), Windows and Glossary of housing terms 247
exterior doors ( 109 ), Exterior covering
materials ( 115 ), Exterior covering Index 257
installation ( 119 ), Exterior trim ( 127 ).
Chapter 5—Specialty features 143
Fireplaces, wood stoves, and chimneys ( 144 ),
Garages and carports ( 151 ), Porches and
decks ( 152 ), Driveways and walkways ( 160 ).
III
PREFACE
The Forest Products Laboratory (FPL), Forest Service, By the early 1980's the need was recognized for a full
U.S. Department of Agriculture, has conducted research revision. The existing text increasingly failed to reflect
related to wood-frame construction since 1910. Initially advances in home building brought about by the avail-
this work was reported in technical papers covering ability of new materials, the use of more manufactured
specific subjects. Popularized versions of some of the components, and changes in construction techniques.
papers were developed to provide guidance to the home- Accordingly, this new edition, incorporating the up-to-
owner as well as the builder. Eventually, the need to date knowledge and expertise of all participants in the
gather this information into a single coherent publication project, has been prepared as a cooperative effort between
became evident. The first complete construction hand- the NAHB National Research Center (a wholly owned
book, written entirely by FPL scientists O.C. Heyer and subsidiary of the National Association of Home Builders)
L.O. Anderson, was published in 1955 as U.S. Depart- and the Forest Products Laboratory (U.S. Department of
ment of Agriculture Handbook No. 73. The handbook Agriculture, Forest Service), with active assistance and
quickly became popular with building professionals and cooperation from organizations forming the steering com-
with the public. Educational institutions adopted it as a mittee acknowledged above.
text and have continued to be major users.
As with previous editions, the handbook emphasizes
As new technology became available and construction the platform construction technique popular in North
practices changed, the handbook became dated. It was America. Information on other techniques and systems,
revised by FPL scientist L.O. Anderson and published such as the truss-framed system developed at the Forest
again in 1970. Slight revisions were made in 1975. Products Laboratory, is available from both the NAHB
National Research Center and the Forest Products
Laboratory.
IV
INTRODUCTION
This book presents sound principles for wood-frame The next three chapters—on laying the groundwork,
house construction and suggestions for selecting suitable framing and closing in, and completing the shell—describe
materials to assist the construction of a good house. It can steps that are usually taken one after the other in the
be used as a working guide to modem construction prac- order that they are set forth.
tice and techniques, as a textbook, or as a standard to
judge the quality of house construction. Dimensions of Chapters 5 through 7—on specialty items, working
wood are always stated as nominal, as explained in the inside, and finishing touches—describe tasks that increas-
technical note on lumber grades. ingly branch out from the ordered requirements of basic
construction and can often be done in some order other
The book's organization reflects the general progression than that presented here, or in parallel with each other.
of activity in building a wood-frame house, from initial
conception to completed structure. Certain steps inevitably Chapter 8 discusses some special topics, questions, and
cut across categories or fail to ñt neatly into any scheme, considerations that are often associated with wood-frame
but the order of presentation reflects the broad sequence construction.
of the building procedure.
An annotated list of suggestions for additional reading
The first chapter describes matters that should be con- and a glossary are provided at the end of the book. Many
sidered or dealt with before beginning construction. of the terms in the glossary appear in the text.
Chapter 1
BEFORE CONSTRUCTION STARTS
Page
Regulation 2
Local regulations ( 2 ), Model
codes ( 2 ), Inspections (2 ).
Financial planning 3
Site selection 4
House design 4
Selecting materials 5
Labor-saving techniques 6
Materials delivery 6
Efficient use of materials 6
Energy conservation 6
Protection of materials 7
Subcontracting 8
Schedule of activity 8
Before Construction Starts
Regulation The organizations and the types of codes they have devel-
oped are as follows:
The construction of a house is a complex process and
requires detailed planning. It is often advisable to engage • BOCA—Building Officials & Code Administrators
the services of an architect or experienced builder to International, Inc.
assist in the process. 4051 West Flossmoor Road
Country Club Hills, IL 60477-5795
Local regulations [phone]
Basic/National Code Series: building, plumbing,
A site may be selected first, or the desired house plan mechanical, fire prevention, energy, and other spe-
may be developed first and a site then selected. In either cialty codes.
case, both must conform to local requirements for house
construction and land use. If a site will not be served by • SBCCI—Southern Building Code Congress Interna-
a sewer system, local codes governing septic systems tional, Inc.
need to be followed. A building permit must be obtained 900 Montclair Road
before construction starts, and periodic inspections by Birmingham, AL 35213
local officials are required during building of the house. [phone]
Standard Code Series: building, plumbing, mechani-
Building code regulations generally include criteria for cal, fire prevention, and other specialty codes.
structural, plumbing, electrical, and mechanical design,
and also cover light and ventilation, egress, fire safety, • ICBO—International Conference of Building Officials
sanitary equipment, and security. Local jurisdictions 5360 South Workman Mill Road
sometimes modify model codes to reflect particular Whittier, CA 90601
requirements in matters such as snow loads, strong winds, [phone]
and seismic activity. Uniform Code Series: building, plumbing, mechani-
cal, fire, and other specialty codes.
In many conmiunities, zoning and subdivision
ordinances and regulations govern the type, density, and • CABO—Council of American Building Officials
use of the buildings permitted and such matters as setback 5203 Leesburg Pike
from the property line. Falls Church, VA 22041
[phone]
Administration and enforcement of building codes and One- and Two-Family Dwelling Code and the Model
ordinances is coordinated through the local building Energy Code.
inspection department, and land use matters are handled
by the zoning department. In many instances, a house The National Fire Protection Association (NFPA), Bat-
plan must be submitted to the building inspection depart- terymarch Park, Quincy, MA 02269, also issues codes
ment and a site plan to the zoning department, and they and standards vital to the housing industry. NFPA pub-
must be approved, by issue of a building permit, before lishes and maintains the National Electric Code and the
construction begins. The staffs of these offices are availa- One- and Two-Family Dwelling Electrical Code. Both
ble to confer with and assist the house builder prior to codes are recognized and referenced by the model code
such formal submissions. It is good practice to meet with organizations in their code documents.
them at an early stage of the planning process to assure
that the formal submission, when it is made, conforms to Inspections
local requirements.
After the building permit has been issued and construc-
Model codes tion begins, inspections are required at several stages of
completion, usually at the completion of footings, fram-
Lx)cal codes, standards, and ordinances are generally ing, electrical work, plumbing, and mechanical features,
derived from model documents. The majority of local and finally of the whole building. You need to schedule
building codes are based on or adapted from codes devel- inspections, as follows, during building.
oped by one or more of four major code organizations.
Footings. These inspections are conducted on the open lender to lender regarding types of loans, loan amounts,
trenches and/or formwork prior to pouring concrete. Steel interest rates, and down payments.
reinforcement, if required, is inspected at the same time.
The depth of the footings below grade is checked to Once you select a lender, the loan office is likely to
insure proper level and footing size, and soil conditions provide guidance regarding professional assistance. They
are checked to insure that the footings provide proper may reconmiend that you seek a professional architect or
bearing. builder to assist in such matters as the final house design,
plan preparation, detailed estimating of labor and
Framing. This must be inspected for grade, size, and
materials, and subcontractor selection.
placement prior to being covered with finish materials.
Some lenders require two loan agreements. One loan is
Electrical and plumbing lines. These are roughed in a short-term construction loan and the other is the long-
while the framing is open. Insulation and vapor barriers,
term mortgage. The construction loan is designed to pro-
as required, are placed in the walls and ceiling and coor- vide the builder with the financial resources necessary to
dinated with the electrical, plumbing, and mechanical pay for the construction of the house as it progresses. A
installations. typical schedule for disbursing the construction loan
money, commonly referred to as a "draw schedule," is
Ductwork and mechanical equipment. These are
as follows:
installed and then inspected. Before any work is enclosed,
they must be inspected and receive approvals for compli- Draw Amount Requirements
ance with building, electrical, plumbing, and mechanical
codes. 1 15% Land survey completed
Building permit issued
Once these inspections are completed and approvals Foundation walls or slab completed
obtained, the interior of the house is ready to receive fin- Floor joists and subfloor in place
ish materials. Insurance policy in place
Final inspection. This is required after all necessary 15% All exterior walls framed and
electrical and plumbing fixtures, duct registers, and/or
sheathed
baseboard units, roofing material, and doors and windows
Roof complete
are installed. The final inspection includes approval of
Well dug, if applicable
numerous other details necessary to finish the house. In
many jurisdictions a certificate of occupancy is issued 10% All interior framing in place
after all final approvals are secured. Heating, plumbing, and electrical
lines roughed in
Financial Planning
Bathtub set
Financial planning should occur early in the precon-
struction process. It is good procedure to visit the loan 20% All exterior walls complete
officer of a lending institution to discuss your plans. Be All windows set
prepared to discuss preliminary house plans, the approxi- All exterior doors hung
mate size and location of the building lot, your income Interior wall covering complete
and other financial resources, and, in general, how the
construction will be accomplished. If you are planning to 15% All trim work complete
do some of the construction yourself, be prepared to Basement floor poured, if
describe your experience and training in order to assure applicable
the loan officer that you are capable of performing the Heating plant in place and
tasks. connected
Septic system completed, if
An experienced loan officer is able to estimate the applicable
approximate costs you can expect to incur based on a
knowledge of the local building industry. In addition to 15% Interior and exterior painting
estimating the cost, the loan officer can estimate the complete
amount of money that you could expect to qualify to Cabinets installed
borrow. All tile work complete
Plumbing, heating, and electrical
It is recommended that you contact more than one lend- fixtures operating
ing institution. Often considerable variation is found from