Cracked block joints

[gonegonzo]

I bought a house and a detached garage . Kind on blew my wawd on the buy some $$$$ is tight .

The garage has several ugly joint cracks in the motar joints . One corner is exceptionally bad .

I studded the inside of the block with 4x4's with bottom and top plates . If the block does give out at least the roof won't fall .

My question is : Is there any way to repair those joints and make them strong without removeing the block ?

I thought of sanwiching them with angle iron with all thread thru the block and angles .

Any advice is appreciated .

Thx ,
Gonzo

 

[davedriveschevys]

Stack and bond mortar comes to mind. But more importantly, do you know why they cracked? A poorly made footing perhaps. Or just a bad mortar job on the joints themselves.

 

[kbs2244]

Stair step cracks are common in block buildings,
They are the result of the settling of the block as the mortar cures.
If the are less that an 1/8 inch then you only have a image problem.
(Until water gets in and the freezes.)

A tuck pointer will grind out the old mortar and stuff in new.
But you might get away with a good thick coat of good paint.

 

[DMT]

I've used this on solid concrete walls with good results. http://www.polygem.com/repair/lcr.php

 

[gonegonzo]

Some of my cracks after chipping out the old mortar , have chack that are 1'' wide . I suspect poor footing but they seem to have not settled after my patching of ''Readyy Mix'' .

I patched them a few yaers back when buying the house . The "ready Mix " seems soft and I don't trust it to be a strong bond .

Thx ,
Gonzo

 

[SRT8]

Hard to really tell without seeing but sounds like water has been running down the side of the wall making the joints weak. Is it both sides of the wall? Are the blocks still pretty much level? If they are, work on one or two blocks at a time being careful not to take out too much material around the whole block until you can get them bonded back a little at a time for example one or two blocks just the bottom horizontal bed joint to begin with. Find and start at the strongest point (harder mortar) & work from bottom up. Whatever your wall thickness is now try to go half of that or at least 2 inches. You can use a regular skill saw with a masonry blade & score the mortar joint you want to replace, a 10 inch grinder would be better. Do all your bed joints first from bottom up & let set up for a day or two. You can tell after you start getting some strength back in your wall,you can do the vertical joints, score them with skill saw too & drill out the upper & lower corners where saw didn't reach, you can chisel some but be careful banging on a weak wall. You need Brixment type S & mix with creek sand. Don't use the sand they sell in the bags. Can usually get sand at a concrete supplier. Mix it good but leaving it thick. You should be able to ball in up in your hand, squeeze open hand & see your knuckle prints. A trowel is best or anything flat to hold mud up level, then use a jointing tool to rake the new mud in. Two jointing tools is best, a thinner one used to rake the new in & a regular one too pack it tightly.

 

[MN BIANCHI]

I have a very old boat house down by the lake that had some badly cracked walls. This boat house was built in the 30's. About 30 years ago I asked an old Norwegian contractor what to do about the cracked walls. His suggestion was to make a small opening at the top of each coarse of hollow block and fill the hollow sections with a soupy mortar mix. That is what I did and it is still holding together after 30 plus years.