How to place a support beam

The most important thing to do before placing a support beam is to calculate the size of the beam you need based on what it will be supporting (which includes the size of rooms and what's in those rooms). Here's a guide to get you started and to ascertain what the steps are you need to follow.

Level of difficulty

Level 2: Intermediate

What you need

• Safety helmet
• Goggles
• Mask
• Adjustable steel props
• Thick plywood or softwood
• Pad stones
• Beam
• Cement
• Sand
• Aggregate
• Mortar
• Bricklayer’s trowel
• Work platform (doubled-up scaffold boards or scaffold tower sections)

The steps to follow

1. Build a work platform by placing doubled-up scaffold boards between steady stepladders, or hire scaffold tower sections. Also consider asking a second person for help, as you'll need help in lifting the beam into position.
2. Knock through the wall with a bolster chisel and hammer to make two holes for the beam. The holes should be 25 cm (10 in) above the lintel. The distance between the two holes should equal to the length of the beam.
3. Cast concrete pad stones where you'll bed the beam to the required size.
   
   Note:
   Use one part cement, two parts sand, and four parts aggregate to make a concrete mix.
    
4. When the concrete has set, bed a pad stone on top of each pier. 
5. Set up the formwork at the required height on each side and check if the two are level.
6. Spread more mortar on the pad stones and set the beam in place.
7. Insert pieces of slate between the beams to fill in the gap. You can also fill the gap with a mortar mix (one part cement and three parts sand). Spread the mortar mix with a bricklaying trowel.
8. Compact it with a wooden batten and a hammer. For large gaps or holes, apply a bed of mortar and rebuild the brickwork on top of the beam.
9. Continue applying mortar on the course between the needles so that when the timbers are removed the holes can be filled in to complete the bonding.
10. Let the mortar set for about two days, then remove the props and the needles and fill in the holes with more mortar.
11. If the beam is fitted against ceiling joists, support the ceiling with props and a board to spread the load on each side of the wall.
12. Cut away the wall, then lift the beam into position and fit a pair of adjustable props under it.
13. Apply mortar to the top of the beam and tighten the props against the joists and brickwork above.
14. Bed pad stones in mortar on both ends.

Related articles

• How to remove a load bearing wall
• How to remove a non-load bearing wall
• How to install wall battens

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