CEILING FRAMES

Created by Michael Martin March 2004 / Revised Feb 2007

• Reference General Construction Knowledge Section 7 – Construct Ceiling Frames (from P278)

• 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 – P279• Joists carry the ceiling sheets and provide a

lateral tie between base of opposing rafters

CEILING TRIMMERS – P279-80• 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 – P280,81• 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 – P280• 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. see page 281

CUTTING HANGING BEAMS P281

• 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 – P282• 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.

SET OUT & ERECTION OF FRAME – from P283

• 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

REVIEW ON WORKSHEET• Review this part of your text book

• In your own words answer the questions on your worksheet

REVIEW ANSWERS TO WORK SHEET

Purpose of frame….

Designed to enclose the room, keep it free

from dust and it also provides insulation and

Security

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

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

Function & position of hanging beams….

To support ceiling joists mid-span, must be supported on load bearing walls & blocked at ends

Fixing to hanging beams by….Joist strap, triple grip, or ceiling dog and should be fixed alternate sides at every

secondjoistHanging beams at external wall ….

Trim hanging beam to pitch of rafterFunction 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