H3 - Build Floor Systems Flashcards
N DECK
What is a sill plate?
Lowest member of a wood frame.
What is the function of anchorage?
Anchor bolts and sill plate make the connection between the foundation and the rest of the structure. Keeps building attached during earthquake or high winds.
What are anchor bolts designed to resist?
Pull out
What kind of walls are required to support floor joists in step foundations, where the top of the foundation wall is shorter?
Poly walls
What is a column?
An upright member supporting a load. It’s also known as a post.
What is the minimum nominal size of a wood column?
6 x 6, but they cannot be smaller in actual dimension than the width of the beam they are supporting.4x4 may be used to support carports.
What is the minimum diameter of a steel column?
Min. Diameter is 3 inches.
What is the minimum size of a round column?
7 and 1/4 diameter
Why are built-up columns more common than solid lumber as column use?
Solid lumber columns are expensive and tend to twist and check as they dry.
What is the advantage of Glue-laminated beams?
Allow for large spans and are able to carry heavy loads. Two standard thicknesses: 80 mm130 mm.Depth varies from: 2228 mm to 456 mm. Maximum span for deepest and thickest is 11.02 m. 36’2”
A W150 x 22 beam means what?
W150 = 150 mm22 = 22 kg per lineal metre.
What is an Laminated Veneer Lumber beam?
An engineered beam, made from sheets of veneer. LVL is usually 1 3/4 thick and comes in widths from 7 1/2 to 16”
What is Parallel strand beams?
Similar to LVL, made from strands of veneer, engineered.4 & 6 inch thick, width vary from 9 1/2 to 16”
What is a girder truss beam?
Common in the roof structure, supports the roof load above, up to 3 ply configuration.
What is the main function of engineered beams and floor joists?
To span between then beams and support the floor sheathing
Which part of the code book must an engineer use to design floor systems?
Part 4 - which specifies the maximum limits of movement for structural members within the systems.
How do you store engineered products?
handle with care, store in a well supported and level or plumb position
What engineered lumber is most common?
The I-joist. Chords are made from lvl, psl or s4sThe webs are made from Plywood, OSB and joined to the chord with a special edge finger joint. The webs are glued to the chords using water proof gliue.Maximum length is 66’
True or False, I joists are in the BC building code?
False
What is another name for open web-joists?
Paralell cord floor trusses
How far can an open web hoist span?
Over 50 feet.
Which type of building use long anchor bolts?
The building which uplift can be created by wind forces & lateral forces caused by wind and seismic events.
What forces are anchor bolts designed to resist?
To support floor and aor wall framing and to anchor the framing to the foundations.
Why is a standard flange steel beam not used in construction?
Because of it’s narrow and sloped flange.
What size of post is used to support a 5-ply built-up wood beam?
5 ply 2 by 6 or rough cut 8 by 8
What do “LVL and “PSL” stand for?
Laminated Veneer Lumber and Parallel Strand Lumber.
Can I joists be designed using tables in the BC building code?
No, need an engineer approval.
What are the three choices for twist restrain given in the building code for floor joist design?
Strapping, briding, strapping AND bridging.
What type of support does bridging provide?
It resists the twisting of the joints as they dry. It distrubes the load from one joint to adjacent joists.
What materials can be used as strapping?
1 by 3 or panel-type ceiling finish (gypsum etc.)
List two types of matched edges used with floor sheathing?
T and G and Shiplap
When planning a floor system, how critical is the elevation of the floor?
If it’s too low, plumbing may not have enough to connect to the sewer system or septic tank.
How high above the finished grade must the concrete wall be?
150 mm, in the case of siding that can be affected by moisture, 200 mm.
How much lower must decks and porches which serve the interior floor be?
150 mm lower
What may result from back-filling before the floor frame i s completely sheathed and braced?
May result in the foundation cracking and falling.
Is the floor system laterally supported when pony walls are used between the sill plate and the floor system?
It is considered laterally unsupported at the top by BC Code
When using the floor system as lateral support, how must you secure it to the sill plate above foundation walls?
Each floor joist is spiked with two toe nails and the boxing rim joist is spiked to the sill plate with angled nails spaced no more than 24” O.c.Boxing joists may be required every 150 mm in high seismic locations.
Sill plates must be anchored to resist what?
Uplift and lateral load.
Whatrt is the maximum spacing for anchor bolts?
2.4 m (8’oc) for 15.9 mm diameter bolts and 1.7 m 5’7 oc for 12.7mm bolts in high-wind or seismic areas.
Within 0.5 m of each foundation corner, how many bolts are required?
One
How many bolts per foundation step and wall panel are needed? (anchor bolt)
2
What is a SIll Gasket?
Protection of the sill plate from the top of foundation wall, prevents.
How is air barrier made under the sill plate of the foundation wall?
Caulking at the inside joint between the sill plate and concrete foundation wall.
What does 1/360 deflection mean?
This means members will sag 1 mm in 3560 mm or 1 inch in 360 inches. for a 16’ beam or floor joist, the allowable deflection will be over 1/2”.
What is the clear span of a joist or beam?
The Horizontal distance from shear point to shear point.
What is the shear point?
The shear point is where the beam or joist leaves it suopport.
Beams used in single spans deflect more than what?
Beams that are continuous over two or more spans.
How can you increase the stiffness of a beam?
Cantilever will reduce deflection and increase stiffness, as a cantilvered beam deflects between its supports, the cantilevered portion of the beam rises.
What is the supported joist length?
The amount of load that a beam carries is propportional to the amount of the floor it supports. The amount of floor is the “SJL”, which is a distance equal to the length of joist suppported by the beam.
Aligning all framing members (studs, floor joists, etc) is it code or not?
Not good, but good practice.
What does using double wall paltes do?
In-wall framing - allows joists and roof trusses to land between stud spaces. The double plate acts as a beam and transfers the load to the adjacent studs.
When the floor system supports a bearing wall, the support for the wall must be continuous to the foundation. True or False
True
If the bearing wall is perpendicular to the joists, the supported wall must be directly over the supporting wall or offset by how much?
3’ for ceiling load and 2’ for floor loads.
Do non bearing walls perpendicular to the floor joists have to be supported by extra joists?
Nonbearing walls perpendicular to the floor joists do not have to be supported by extra joists.
How must plywood be installed on joists?
90 degrees to the joist direction and the end joints for adjacent rows staggered.1.55 5/8 thick ply can be used on joists over 400 mm 16” ocand 18.4mm 3/4” for joists spacing at 600 mm 24” oc
How much oriented strand board be installed?
Osb must be installed with the face orientation 90 degrees to the joist direction and the end joints staggered.15.9mm 5/8 OSB can be used on joists at 400 mm 16” o.c and 19 mm 3/4 for joists spacing at 600 mm 24” oc