Framed floors Flashcards
What are the two primary materials that piles can be made from?
H5 Timber, Concrete
What is the main function of ordinary piles?
To resist vertical loads (compression or tension).
Where are ordinary piles commonly used?
In situations where the load-bearing capacity of the soil is insufficient.
What is the minimum depth at which ordinary piles should be placed into the ground?
200mm
What is the maximum height above ground level for ordinary piles?
3 meters
How are bearers attached to ordinary piles?
Bearers are run directly over the pile and fixed with 2 nails and wire dogs or 4 nails.
What type of pile is used to resist horizontal forces such as wind or seismic activity?
Anchor pile
Where are anchor piles typically used?
In areas prone to landslides.
What is the minimum depth for anchor piles?
900mm
What is the maximum height above ground level for anchor piles?
600mm
How are bearers fixed to anchor piles?
Bearers are run along the side of the piles and attached with M12 bolts and 3mm washers.
What are braced piles used to resist?
Both horizontal and vertical loads.
Where are braced piles typically used?
In deep excavations.
What is the minimum depth for braced piles?
450mm
What is the maximum height above ground level for braced piles?
3 meters
At what angle are braces typically attached to braced piles?
Between 10 to 45 degrees.
How many braces can be attached to a pile?
No more than two braces at the bottom, and only one at the top of the pile.
What is the primary use of driven/cantilever piles?
Primarily used in poor soil conditions, often for retaining walls.
What is the maximum length for driven piles?
3.6 meters
What is the minimum depth for driven piles in gravel?
900mm
What is the minimum depth for driven piles in other soil types?
1.2 meters
How are bearers attached to driven piles?
Bearers are run directly over the pile and fixed with 2 nails and wire dogs or 4 nails.
What is the only reason to dig a pile hole deeper than the minimum specified depth?
To reach a depth where the bearing capacity of the soil is sufficient.
How much space should be left for concrete under a pile?
100mm
How do pile foundation joints differ from pole frame construction?
In pile foundations, bearers are run directly on top of the piles, while in pole construction, bearers are bolted to the outside of the poles.
What is the minimum timber treatment for subfloor timber when it is close to the ground?
H5
What is the importance of where bearers should join and how these joints are arranged over multiple rows of piles?
Load distribution, structural continuity, and redundancy
What should be placed between pile and bearer junctions, and why?
A Damp Proof Course (DPC) to prevent moisture from rising from the ground to the bearers.
How does the height above ground affect timber treatment of subfloor framing?
The closer the timber is to the ground, the higher the risk of moisture penetration.
What is the role of subfloor ventilation in timber foundations?
To remove moist air from under the building, preventing moisture damage.
How many air changes per hour are required for wet sites according to building code E2?
10 air changes per hour
What are common forms of subfloor ventilation?
Vents, ventilation pipes, raised floor spaces, drainage systems, and elevated foundations.
What else is done to prevent subfloor moisture from entering a building envelope?
A Damp Proof Course (DPC), higher ground level, and drainage systems.
What is the purpose of a ribbon plate in floor framing?
It attaches to the house and serves as a connection point for the floor framing.
What should be checked before placing and fixing timber in floor frames?
Straightness (to avoid uneven floors).
What are some types of timber flooring used in construction?
Laminate, particle board, pine plywood, hardwood (e.g., oak or rimu).
How should sheet or lineal flooring be oriented relative to framing for maximum strength?
It should be installed perpendicular to the floor joists, and joints should be staggered over joists.
What is the most important thing to check as you lay and fix off decking timber?
Ensure it is square with the framing and installed straight.
What are the three most common methods for fixing flooring to framing?
Nails, screws, and glue.
What is secret nailing?
Nailing through the tongue in a tongue-and-groove system, with the groove covering the nail.
What hardware is used to connect piles to bearers?
Z nails
What hardware is used to connect bearers to joists?
Z nails, CPC 40/80
What is used to connect joists to boundaries/ribbons?
Joist hangers
What hardware is used to attach boundaries/ribbons to an existing structure?
Bolt and washer
What is used to connect joists to ribbon plates?
Hurricane tie
What factors influence the choice of hardware for timber construction?
Material, exposure to weather elements, durability, and rust protection.
What are trimmer joists used for in floor framing?
They form the openings for stairs or access hatches.
What is the role of the header in stair openings?
It supports the stair framing and helps transfer loads.
What height difference requires a building consent for a deck?
A fall of 1.5 meters or more.
What is the minimum gap required between a deck and cladding?
12mm
