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CEILING FRAMES. Created by Michael Martin March 2004 Revised Feb 2007 / Mar 08 / Mar 2010. Look at this picture, can you see the different members ?. Reference: Basic roof & ceiling text ‘Carp’ notes – P 10
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CEILING FRAMES Created by Michael Martin March 2004 Revised Feb 2007 / Mar 08 / Mar 2010
Reference: Basic roof & ceiling text ‘Carp’ notes – P 10 • Definition: The ceiling frame is the horizontal area between the top of walls and the roof • Consists of: ceiling joists, trimmers, hanging beams and counter beams
CEILING JOISTS – P10 • Joists carry the ceiling sheets and provide a lateral tie between the base of opposing rafters
CEILING TRIMMERS – P11 • Sometimes called trimming joists, short lengths at right angles between ceiling joists. Give fixing to ends of ceiling sheets and can provide fixing for internal walls.
HANGING BEAMS – P12 • These provide support to the ceiling joists mid-span, must be blocked at ends and if large sections may need to be strapped
Trimmers Ceiling Joists Hanging beam
SUPPORT TO JOISTS – P 12 • There are three common types of support between ceiling joists and hanging beams, joist straps, triple grips and ceiling dogs
Remember: Hanging beams go above the joists, so we have to block the ends.
CUTTING HANGING BEAMS - P13 • Where hanging beams run across ceiling joists with end protruding past the rafter line as in a hipped roof, they must be cut but also supported via a trimmer
COUNTER BEAMS - P 14 • Counter beams run at 90deg. To the hanging beam and supports it when it’s length exceeds it’s allowable span, ends of counter beams are packed slightly to allow for deflection.
Counter Beams Supports hanging beam mid - span
SET OUT & ERECTION OF FRAME - P15 • GABLE ROOF • the set out of the ceiling frame is based on the set out of the rafters • First check top plates for straight & square • Mark position of gable end rafters • Then work from one end, set out position of common rafters, other side of line becomes joists • See sketch
Next cut all ceiling joists to length and fix into position, double skew nail • Cut and fix ceiling trimmers to ends • Cut and fix trimmers above internal walls where required
Lastly fit hanging beams to the centre of the ceiling joists length over each room as required • Remember fixing and blocking for hangers
Quick Questions ! What is the purpose of ceiling frame…. ? Designed to enclose the room, keep it free from dust and it also provides insulation and Security What is the function of ceiling joists… ? The horizontal member that carries the load of the ceiling sheets and act as a tie between the rafters at their base
Quick Questions Review
What is the function of trimmers…. ? To provide fixing for ends of ceiling sheets, also internal walls where they fall between joists and help give lateral stability to frame What is the function & position of hanging beams…. ? To support ceiling joists mid-span, must be supported on load bearing walls & blocked at ends
How can we fix hanging beams…. ? Joist strap, triple grip, or ceiling dog and should be fixed alternate sides at every second joist What do we do to hanging beams at external wall …. ? Trim hanging beam to pitch of rafter What is the function of counter beams…. ? Run 90 deg. to hanging beam and provides support to them where they exceed their own span
Set out and erection… • Check top plates are straight and square • Mark gable end rafters at each end • From one end set out common rafters marking each side of line for (r) rafter and (j) joist • Cut joists to length and fix into position, double skew nail • Fix trimmers to ends and where required for internal walls • Fix hanging beams to the centre of joists length in rooms required • Provide strapping where required