Suspended Timber Floors Flashcards
How are jiffy hangers secured to the joist?
30 – 40 mm twist nails
What is the name of the joist that spans wall to wall?
Bridging Joist
What is the name of the joist that spans from wall to wall and supports the trimmer joist?
Trimming joist
What is the name of the joist that spans from the wall to the trimmer?
Trimmed joists
How much thicker is a trimming joist than a bridging joists?
minimum of 25mm thicker, can be 2 bridging joists.
How far from the wall is the first joist positioned?
50 – 60mm
Where would you find a sleeper wall in floor construction?
Ground floor to support the joists,
Why do timber ground floors require ventilating?
To keep the moisture content below 18 percent, prevent rot and corrosion.
At what span is a row of strutting required?
Greater than 2.4m requires a row of strutting.
At what span are two rows of strutting required?
Greater than 2.4m requires a 1 row of strutting and greater than 4.8 requires 2 rows.
if a joist is found to be bowed how should it be positioned in the floor construction?
Installed with the bow at the top of the joist.
Where would be the best place in a joist to drill a hole for a cable or pipe?
Centre of the joist in a neutral stress zone.
Why must strutting between joists be kept 10mm from the top and bottom of the joist?
To prevent the strutting fouling the floor and ceiling coverings.
What are the advantages of heron-bone strutting over solid strutting?
Easy to install services, uses less timber.
What is the purpose of strutting between joists?
Prevents joists twisting.
What material should be used to pack joists to get them level?
Slate or nylon packers
What governs the joist spacing?
The span, the floor covering thickness & the floor load.
State two methods of supporting joists?
Built-in, hangers, bolted wall-plate & steel joists.
What is the purpose of perimeter noggins in a floor?
To support the edge of the flooring and ceiling coverings.
What are the dis-advantages of using heron-bone strutting over solid strutting?
Takes longer, costs more in labour.
State three different types of joists used in floor construction.
Solid timber, timber ‘I’ beams, eco joists, web joists
What part of the building regulations covers floor construction?
Part A
What visual safety checks would you carryout on your circular saw before using it to cut the joists to length?
Check the body of tool for damage, check battery connections, check guard operates correctly, check cable for damage.
What health and safety regulations are complying with when installing joists.
HASWA, PUWER, WAHR, PPE reg, Manual handling regs, COSHH
