Light-framed construction refers to a building technique that uses relatively lightweight materials, such as wood or steel, to form the structural framework of a building. It is commonly used in residential and low-rise commercial buildings. In this method, the structure is built using smaller members (such as studs, joists, and rafters) that are typically spaced at regular intervals.
According to the International Residential Code (IRC), the minimum required size for the largest habitable room in a dwelling unit is 120 square feet. All other habitable rooms, other than the kitchen, must be at least 70 square feet.
How are the maximum allowable spans of floor joists determined? What design liveloads are to be used for joists supporting sleeping rooms? For areas other than sleeping rooms? For attics accessed by a permanent stairway?
The maximum allowable span of floor joists is determined by calculating the load they need to support (based on the design live load and dead load) and then referencing a span table specific to the joist size and species, which will indicate the maximum distance they can span between supports while meeting the required deflection limits; for sleeping rooms, the design live load is typically 30 pounds per square foot, while for other areas, it is usually 40 pounds per square foot; for attics accessed by a permanent stairway, the design live load is also typically 30 pounds per square foot.
How is the maximum allowable spacing of wood studs determined? How is a double top plate to be installed? A single top plate?
The maximum allowable spacing of wood studs is primarily determined by the load the wall needs to support, local building codes, and the type of stud used, with most codes specifying a standard spacing of 16 inches on center for load-bearing walls; non-load bearing walls may allow for wider spacing, but always consult local regulations.
Wood stud walls shall be capped with a double top plate installed to provide overlapping at corners and intersections with bearing partitions. End joints in top plates shall be offset not less than 24 inches. Joints in plates need not occur over studs. Plates shall be not less than 2-inches nominal thickness and have a width not less than the width of the studs.
Exception: A single top plate used as an alternative to a double top plate shall comply with the following:
The single top plate shall be tied at corners, intersecting walls, and at in-line splices in straight wall lines in accordance with building code tables.
The rafters or joists shall be centered over the studs with a tolerance of not more than 1 inch.
Landings must be located on the exterior and interior portions of an exterior door. The landings must be a minimum of 36-inches in length and be at least the same width as the door. There is an exception for exterior balconies that are less than 60 square feet and only accessible from a door.
When is roof ventilation required? What is the minimum required ventilating area? How can this area be reduced?
Roof ventilation is generally required when you have an enclosed attic space, and the minimum required ventilating area is typically considered to be 1 square foot of net free ventilation area for every 150 square feet of attic floor space, which is often referred to as the “1/150 rule”; this area can be reduced in certain circumstances by meeting specific conditions like installing a vapor barrier in certain climate zones, allowing for a 1/300 ratio instead.
What is a climate zone, and how is it determined? How does the climate zone relate to the energy efficiency requirements?
A climate zone is a geographical region categorized by its distinct long-term weather patterns, primarily defined by temperature and precipitation levels, which are used to determine the most appropriate energy-efficient building practices for that area; essentially, the more extreme the climate, the stricter the energy efficiency requirements will be in that zone to minimize heating and cooling needs.
In what seismic design categories must water heaters be anchored or strapped to resist horizontal displacement due to earthquake forces?
What prescriptive method is set forth.
According to most building codes, water heaters must be anchored or strapped to resist horizontal displacement due to earthquake forces in Seismic Design Categories C, D, E, and F; the prescriptive method is to strap the water heater at points within the upper one-third and lower one-third of its vertical dimensions, with the lower strap positioned at least a four inches above the controls.
How is a range hood required to be ducted? What are the physical characteristics of the duct? What materials are permitted for duct construction?
Range hoods shall discharge to the out doors through a single-wall duct. The duct serving the hood shall have a smooth interior surface, shall be air tight and shall be equipped with a backdraft damper. Ducts serving range hoods shall not terminate in an attic or crawl space or areas inside the building.
An unventilated crawlspace is required to have 100% floor vapor barrier sealed and extended at least 6-inches up the stem wall. The vapor barrier must be attached and sealed to the stem wall or insulation.
In reference to Writing Assignment #1
What is the purpose and scope of the International Residential Code?
The International Residential Code is intended to regulate construction, maintenance, and alterations of one and two family dwellings, as well as townhouses that are three stories or less in height. It is intended to protect the health and welfare of the occupants by outlining minimum standards for residential construction.
ICC study; * How must roof drainage water be discharged? R903.4: Unless roof are sloped to drain over the edges, roof drains shall be installed at each low point of the roof.
Can deck guard posts be notched?
No. “Where 4-inch by 4-inch wood posts support guard loads applied to the top of the guard, such posts shall not be notched at the connection to the supporting structure.” R507.10.2
What is the criteria for the installation of weep screeds in exterior plaster applications?
A weep screed installed on exterior stud walls in an exterior plaster application must be placed a minimum 2-inches above paved areas and a minimum 4-inches above the earth. The weep screed must allow trapped water to drain out. The weather barrier must lap the attachment flange and the exterior lath must cover and terminate on the attachment flange of the screed.
What are the installation requirements for asphalt shingles?
Asphalt shingles shall be used only on roof slopes of 2 units vertical in 12 units horizontal (17-percent slope) or greater. For roof slopes from 2 units vertical in 12 units horizontal (17-percent slope) up to 4 units vertical in 12 units horizontal (33-percent slope), double underlayment application is required. R905.1.1
What special conditions apply to the installation of a solar energy system?
Access shall be provided to solar energy equipment for maintenance. Solar systems and appurtenances shall not obstruct or interfere with the operation of any doors, windows or other building components requiring operation or access. Roof-mounted solar thermal equipment shall not obstruct or interfere with the operation of roof-mounted equipment appliances and chimneys.
At what minimum height is a masonry chimney required to terminate?
A masonry chimney must terminate at a minimum height of 2 feet higher than any part of the building within 10 feet, and not less than 3 feet above the roofline where the chimney passes through.
How high above a floor in a garage is an appliance with an ignition source required to be located?
Appliances having an ignition source shall be elevated such that the source of ignition is not less than 18 inches (457 mm) above the floor in garages. There is an exception for appliances that are listed as flammable-vapor-ignition resistant. There is no clearance requirement for FVIR rated appliances.
Which sources of outside or return air are prohibited?
Return air shall not be taken from a closet, bathroom, toilet room, kitchen, garage, mechanical room, boiler room, furnace room or unconditioned attic.
Writing Assignment #12 - A chimney connector shall enter a masonry chimney not less than 6 inches above the bottom of the chimney. Where it is not possible to locate the connector entry not less than 6 inches above the bottom of the chimney flue a cleanout shall be provided installing a capped tee in the connector next to the chimney. The area of chimney flues connected to more than one appliance shall not be less than the area of the largest connector plus 50% of the area of additional chimney connector.
What is the maximum permitted length for an appliance fuel connector serving a range or domestic clothes dryer? Serving other appliances?
Connectors shall have an overall length not to exceed 3 feet, except for range and domestic clothes dryer connectors, which shall not exceed 6 feet in length. Connectors shall not be concealed within, or extended through, walls, floors, partitions, ceilings or appliance housings.