Remedial wall ties in pillar - type and positioning?

[andreas]

We have a narrow pillar between two windows - 1.5 bricks width, 1m height. The brickwork has nothing above, just the soffit sat on it. One of the windows had to be replaced, during which the pillar was disturbed causing several courses of mortar to hairline crack, the installer said that pillar appears to have no wall ties at all into the ash-block inner leaf but only told me this after they had finished work.  The wall ties around the rest of the house were checked previously and are in very good condition so it does sound like the installer is correct that they might be missing.

What would be the best type of remedial wall ties to fit and how many would you recommend, at what spacing? After fitting I was intending to take out around 50% of the depth of mortar and re-pointing the pillar to finish up.

[Mr Punter]

I think you may find it tricky to do much as you will need to drill / hammer to get any ties in and this will disturb the brickwork further. Maybe helical ties would work?

[andreas]

1 hour ago, Mr Punter said:

I think you may find it tricky to do much as you will need to drill / hammer to get any ties in and this will disturb the brickwork further. Maybe helical ties would work?

I was thinking helical before I found out how many other types are available. The pillar is obviously weakened but not fragile, the window installer drilled into it for the window fixings so I think I should be fine drilling. I may sort the mortar out first to give it a bit further strength back? I am not sure on how many ties to put in or where though.

[Mr Punter]

Can you space them at 300mm (4 bricks) vertically, staggered each side of the pier, 100mm in?  That would give you about 6-8 ties.

[andreas]

1 hour ago, Mr Punter said:

Can you space them at 300mm (4 bricks) vertically, staggered each side of the pier, 100mm in?  That would give you about 6-8 ties.

Yes that it very doable.