Blocks on Lintels

[LSB]

Looking for some advice on brick / block laying.

We have built up 2 single storey cavity wall to Lintel level and am now running my blocks across the top of the steel lintel. The problem that we are having is as we set each block (7n H&H blocks approx. 9Kg) they seem to “skate” on the mortar, regardless of how dry we mix it.

When we am laying block on block there is no problem, a tap with the mallet and the block moves a small predictable amount. On the Lintel they seem to slide about like a bag of monkeys. Is there a trick of the trade that we are missing or some way to overcome this ?

[Russell griffiths]

Set the lintel and let it go off. 
the lintel will be set slightly further back than the face. 
get a piece of timber and set it level with the lintel and prop it from underneath, lay the blocks with a mortar bed angled inwards. Lay the blocks to a level until they sit down and touch the timber. 
allow to go off and remove timber. 
 

in this weather they can slide all over the place. 
 

@Canski might have some tricks up his sleeve. 
 

don’t forget your cavity tray and weep holes. 

[Conor]

I remember a detail on our drawings showing that steel mesh should be spot welded on top of beams where blocks were to be built off. Not sure if that applies to galvanised lintels tho.

[Canski]

Put a temporary timber prop under the lintel ( I use 4 X 1 ) and the same length as the opening in line with the blockwork each side. Then prop it each side from below, if the opening is longer than 1500 mm you may need extra props in the middle. Lay your course of blocks on top of this and leave it until the mortar has almost set (overnight is ok). Do not go any higher than one course over the lintel. The next day you can remove the props and scrape back any excess mortar from the toe of the lintel. If it’s still soft put the prop back in and continue.  

Edited January 27 by Canski