Vertical crack in Garden boundary wall

[Phil0884]

Hello, first time poster but long time reader. In the last month a vertical crack appeared in my garden boundary wall.

The crack spans the complete width of the wall so you can see the crack on both sides of the wall. The wall borders an alleyway and is 6ft high so I wanted it investigated, a builder had a look and as the wall wasnt showing any signs of leaning he was confident it was unlikely to collapse as the rest appears in good condition with no trees in close proximity.

He suggested I could use some slip ties otherwise replacing the section would be £1100 plus materials.

Money is not plentiful and I'm not keen on these slip ties so I've been looking at these helifix stitches and what people's thoughts were on them?

If I do use helifix stitches I'd have to put them in on the alleyway side (and remove the render) as the crack is too close to the pier on the garden side for a helifix stich to go in.

Any thoughts on the best course of action and people's opinions on the helifix stitches most welcome and any other suggestions people may have. Many thanks, Phil

 

[George_engineer]

How long is the wall? The original cause is probably contraction of the blocks (new blockwork should have movement joints at 6m spacing). But if it's now been there for a while and all contraction has stopped, helifixing could be done.

However if it's longer than 6m then a movement joint could be worth it as future thermal expansion and contraction comes into play.

 

[^woody^]

Thats contraction and if you use any crack stitching it may well crack again in another location.

Your builder's slip tie idea may well be best. Same concept but instead of building in spiral ties, build in a slip tie and sleeve

 

[Bouy]

Is the crack wider at the top than the bottom, could just be foundations settling more one side than the other due to drying ground shrinkage ( recent hot weather) and breaking foundations back. How old is the wall

 

[Phil0884]

Wall section is approx 10m, builder who looked at it reckoned it was around 50 years old judging by the blocks used. No expansion/movement joints though it does change from block to brick either side of this 10m section.

Crack is wider at the top (about 3mm). I did wonder whether is had been the long period of got and dry weather that had contributed to this but given its 50 years old with no other cracks visible I'm not sure.

Builder dropped off some slip ties for me to use but they don't have the plastic sleeves

 

[Bouy]

So its stood the test of time, its not leaning so foundations appear good except for ground shrinkage,mix some mortar and push it into the crack as best you can, repaint and report back in 10 years time