General Building Specs
Please use this helpful information during the building process of your new home.
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1. Dimensions
Drawing dimensions govern over scale. Verify all rough opening dimensions for selected doors, windows, and mechanical requirements before construction begins.
2. Design Load Criteria
Unless otherwise noted, the drawings are based on the following load criteria.
Allowable soil bearing pressure is assumed to be 2,500 p.s.f. or greater.
NOTE: Verify design loads with local codes and site conditions. Check with local building department officials for wind, seismic, snow or other special loading conditions. If unusual site conditions exist, or local building requirements exceed the above design criteria, consult with a local architect, engineer or qualified designer to adjust the foundation design and other structural elements if necessary.
3. Concrete
Unless otherwise noted, all concrete foundation walls and slabs on grade shall be 3,000 p.s.i. (28-day compression strength) concrete. Place concrete slabs on 4" of compacted gravel fill with 6" x 6" - W 1.4 x W 1.4 wire mesh reinforcement. All slabs under interior finished and heated living spaces shall be placed on 6-mil polyethylene vapor barrier with a minimum of 6" lapped joints.
Provide 1/2" expansion joint material between all concrete slabs and abutting concrete or masonry walls occurring in exterior or unheated spaces or areas.
4. Structural
A. The truss manufacturer (if trusses are specified on plans) shall submit shop drawings and/or stress and load calculations (diagrams) for contractor's approval prior to construction. Diagrams shall bear seal of registered engineer in the state the structure is built.
B. Install rafter or truss tie-downs, Simpson #H7 or equivalent at each truss bearing point and/or every other rafter bearing point.
C. Solid wood beams shall have an allowable bending stress of 1,500 p.s.i. and a modulus of elasticity of 1,760,000 p.s.i. Composite wood beams (constructed of 3 or more members) and repetitive members (e.g..joists, rafters) shall have an allowable bending stress of 1,200 p.s.i. and a modulus of elasticity of 1,500,000 p.s.i. Changes in the member size or structural characteristics will alter the integrity of the floor and roof system design.
D. All structural panels (plywood, waferboard, composite, particleboard, oriented strand board) shall bear the BASIC GRADE TRADEMARKS of the American Plywood Association.
E. All structural steel beams and columns shall conform with the American Institute of Steel Construction Specifications A36.
F. All masonry over wall openings shall be supported with one steel angle (or an equivalent load-bearing member) for each 4" thickness of masonry supported as follows with longer leg of angle positioned vertically:
Opening Size |
Angle Size |
|
Up to |
4' - 0" | 4 x 3 x 1/4" |
| 5' - 0" | 4 x 31/2 x 1/4" | |
| 6' - 0" | 5 x 3 1/2 x 5/16" | |
| 7' - 0" | 6 x 31/2 x 5/16" | |
| 8' - 0" | 6 x 4 x 3/8" |
G. Masonry veneer shall be attached to supporting wall with corrosion-resistant metal ties. Ties shall be spaced not more than 32" O.C. horizontally and not more than 16" O.C. vertically.
5. Foundations
A. Check the depth of frost line(s) for footing depths and verify footing requirements with local code officials. Consult with local architect or engineer when encountering unusual or unstable soil conditions.
B. Unless otherwise noted, masonry foundation walls shall be constructed with:
1. Grade "N", Type 1, hollow load-bearing concrete masonry units.
2. Type "M" mortar.
3. Horizontal joint reinforcing, (ladder or truss type) continuous, every other block course.
4. Reinforce walls of excavated areas which exceed 4'-0" in height with #7 vertical rebars full height at 4'-0" O.C. and at each corner and both sides of openings. Fill all cells containing vertical bars with cement grout.
5. Fill entire top course with stiff grout. C. Unless otherwise noted, cast-in-place concrete foundation walls shall not exceed 8'-0" in height and shall have a minimum wall thickness of 8". Reinforce with two #5 horizontal bars in upper and lower 12" sections of wall and with #3 bars placed vertically every 18" O.C.
D. Place 1/2" diameter x 12" long anchor bolts at 6'-0" O.C. set a minimum of 8" into concrete and within 12" of end of each sill plate member to secure sill plate to foundation.
E. Basement walls shall be treated as follows:
1. Apply two coats (minimum) of troweled or sprayed-on waterproofing; compound to exterior wall surface of excavated areas.
2. For foundation wall drainage, install 4" minimum diameter drainage tile or perforated pipe at the perimeter of excavated areas and below finished basement floor slab elevation (when applicable). Cover top of pipe with 15-pound felt and a minimum 18" course of rock or gravel. Slope pipe to drain or sump pump as required.
F. All grades to slope away from foundation a minimum of 1"; fall per foot for a distance of 8'-0" or to a swale. Use concrete splash block or drain pipe at each downspout to direct roof run-off away from foundation.
G. Provide termite protection as required and remove all wood construction materials from the excavation near the structure.
6. Carpentry
Unless otherwise noted on drawings, provide:
1. Double header joists and trimmers at all floor openings where joists terminate.
2. An extra joist under all parallel partitions.
3. Double 2x10 headers with 1/2" rated plywood between, at all door and window openings.
4. Minimum of one row of joist bridging per joist span.
5. Floor construction: use 1/2" plywood sheathing with exterior glue under 5/8" particle board underlayment for carpet and ceramic tile areas. Substitute 5/8" underlayment grade plywood where sheet vinyl floor covering is used. (Optional 3/4" tongue-and-groove plywood floor system may be used in lieu of the two-layer floor system.)
6. Roof construction: Minimum 210# asphalt shingles (adhesive type) or equivalent on 15# felt on 1/2" C-D exterior plywood sheathing on roof framing; sheet metal flashing where roof abuts any vertical surface.
7. Corner bracing: Approved diagonal corner braces in both directions at all corners. (Optional 1/2" or 3/4" x 48" wide C-D exterior plywood both directions at all corners.)
8. All interior walls and ceilings are to be covered with minimum 1/2" gypsum board with exterior corners metal reinforced. Surfaces to be taped, floated (3 coats) and sanded. Water resistant gypsum backer board is required around bathtubs and showers.
9. Interior walls and ceiling of garage to be covered with minimum 5/8" fire code gypsum board. Door(s) leading from garage to living space shall be 3/4 hour fire rated. Fire stop all, duct chases, bulkheads, laundry chutes, metal flues, and all shafts at each floor.
10. Glass in storm doors, doors intended for human passage, patio doors, shower and bathtub enclosure walls, panels and doors, to be fully tempered, laminated safety, approved wired glass or approved shatter resistant plastic.
7. Insulation
Unless noted on drawings, provide:
1. Minimum R-ll batt insulation in all exterior walls, minimum R-30 insulation in all attics and cathedral ceilings, and minimum R-19 batt insulation in all floors adjacent to the exterior or to unheated spaces.
2. When using unfaced insulation, install minimum 6 mil polyethylene vapor barriers against warm side of all insulation.
3. All exterior windows are to be insulating double glazed.
4. Caulk and seal at all windows, exterior doors, vents, pipe penetrations, bottom plates and around all electrical boxes mounted in exterior walls.
5. Install sill sealer between foundation wall and wood sill plates.
8. Ventilation
A. Roof vents and/or gable vents shall be used in conjunction with soffit vents to provide adequate removal of summer heat as well as winter moisture.
B. Attics and spaces between roof and top floor ceilings shall have a minimum of one square inch of free vent area for each square foot of ventilated space. This required vent area may be reduced by one-half when at least 50 percent of the required vent area is provided by vents located in the upper portion of the space to be ventilated, with the remainder of the required ventilation provided by eave or cornice vents.
C. The space between the bottom of the floor joists and the earth (except such space as is occupied by a basement) shall have a minimum clear height of 18" and a minimum net area of ventilation openings through the foundation of not less than one square foot for each 150 square feet of crawl space area. If an approved vapor barrier is installed over the ground surface, only 10% of the above vent area is required.
D. Baths with no operating windows shall be mechanically vented.
9. Electrical Work
All electrical work shall comply with all codes in effect in the local community. Where no codes exist, the work shall conform with the regulations of the National Electrical Code and the electric utility company servicing the area.
10. Plumbing
A. The contractor shall furnish and install all soil, vent, and waste piping, the hot and cold water supply system, the plumbing fixtures and fittings, and the connections to the potable water supply and to the sewers as directed.
B. The contractor shall obtain all permits and inspections as required by state and local codes, and all work shall be in accordance therewith.
11. Heating and Air Conditioning
A. The heating contractor shall furnish an engineered heating layout in conformance with local codes, and shall install a complete heating and cooling system of the type selected by the owner.
B. The heating system and air-conditioning system shall satisfy local weather conditions in accordance with the design practices recommended by ASHRAE, and shall conform to the rules and regulations of the National Board of Underwriters and any and all governing local and state codes.
12. Miscellaneous
A. These specifications have been developed and issued without knowledge or reference to a specific geographic location. Therefore, supplemental to these documents is the owner's and his builder's responsibility for following material and equipment manufacturers' instructions, using recognized standards for each building craft and trade, and complying with all governing code requirements for the geographic area in which this house is to be built.
B. Home Design Alternatives sells house plans to assist in the construction of new single family and multi-family residences. However, in some markets, building regulations or codes may require that the plans and specifications be prepared under the supervision of an architect licensed in that jurisdiction. Where such regulations or codes apply, compliance is the responsibility of the owner and/or contractor.
C. It is the responsibility of the owner and contractor to verify with local building officials that details on these blueprints and specifications DO COMPLY with ALL applicable codes prior to beginning construction.
