Repairing Concrete

**Denny Crane!** · July 22, 2014, 06:52 PM

Seriously. Odd topic but I thought I'd give it a go.

Looking to repair some long fairly serious (dormant) cracks in large concrete blocks and wonder if there are any tradesman on TWC. Got my handsful learning enough other things could do without going through all of the rigmaroll of gaining specialist knowledge in concrete as well! Long story short crack came from industrial digger used nearby to dig in to get to a broken water pipe. Stable and dormant but house is up for sale and it is a high value property, we'd like to repair the cracks and preferably hide the fact that they've needed repaired through sanding etc. I did a rough mix of cement and whacked it in today, it isn't bad but not great.

Any advice?

**Flinn** · July 23, 2014, 03:34 AM

I have some experience with concrete use (as I often do jobs myself at home), but if you want a good job, go for a professional; if it is for a property on sale, definitely go for a professional

Have you considered to ask to the company that was dealing with the tube repairing to also repair the concrete? in the end, it was their fault.. no?

Is the block standing or lying? At any rate, there are products in commerce to properly and easily repair cracks on concrete, but it will be evident that a repair has been done. If you insist to go with it by yourself you can think of scratching completely the part that has the crack on a rectangular shape and make it new (but will work only if lying on the ground); don't forget to put a steel net into (size depending on the size of the crack itself).

Another possiblity, if the block is standing: once you did the repair, spread out a thin layer of plaster to make a brand new surface over the concrete (though probably if you have many standing blocks, it is better if you make it in white color and then give a hand of white painting to the rest of them)

If you have a picture, would be useful to understand better

Hope it helps sir

**Nazgûl Killer** · July 23, 2014, 06:22 AM

Sorry mate but this really isn't for the PH&A, as such, I'll be moving it to the TD.

**Ishan** · July 24, 2014, 03:37 PM

**Denny Crane!** · July 24, 2014, 03:59 PM

Originally Posted by Flinn

I have some experience with concrete use (as I often do jobs myself at home), but if you want a good job, go for a professional; if it is for a property on sale, definitely go for a professional

Have you considered to ask to the company that was dealing with the tube repairing to also repair the concrete? in the end, it was their fault.. no?

Is the block standing or lying? At any rate, there are products in commerce to properly and easily repair cracks on concrete, but it will be evident that a repair has been done. If you insist to go with it by yourself you can think of scratching completely the part that has the crack on a rectangular shape and make it new (but will work only if lying on the ground); don't forget to put a steel net into (size depending on the size of the crack itself).

Another possiblity, if the block is standing: once you did the repair, spread out a thin layer of plaster to make a brand new surface over the concrete (though probably if you have many standing blocks, it is better if you make it in white color and then give a hand of white painting to the rest of them)

If you have a picture, would be useful to understand better

Hope it helps sir

I'll take some pics on saturday, they are very large standing steps. I'm a plasterer with little concrete experience unfortunately, if it was tanking inside with plaster I'd be on firmer ground as I usually do it with damp proofing. Now I went ahead and did the repair though by chance I've picked the right method I think looking at Ishans post below (hope!), I ground it out to create a nice small but effective V and filled it, and the bit at the end of the first video should be enough to mask it as well as protecting the concrete that is exposed to a lot of Ice and cold/damp and potentially grit/calcium in the winter being kicked up from a main road 20 foot above (house is built into a hill these steps run down from the road).

Originally Posted by Ishan

You beautiful human being. That first video with the concrete protection paint is exactly what I was looking for. My repairs will be hidden with due diligence in protecting it

And I ground it out and used the right materials in the repair by a mixture of luck and a much smaller amount of good guesswork. I'm going to watch the rest with interest thank you.

I had no idea Concrete needed protection to keep it from cracking. Good experience this little renovation.

Now who knows about ponds and streams!

Seriously I've got a very badly designed pond and stream to repair, I've got a feeling it could look amazing with some work.

**~~RubiconDecision~~** · July 25, 2014, 04:10 PM

Remember that if you're using power tools on concrete that you need special masonry bits. Say you're drilling into it, without a masonry bit then the bit will dull rapidly because it's not made for concrete. Ask questions at the hardware store specific to working with concrete and skip the normal teenager working in that aisle, but go to the craftsman expert to get tips. Good luck.

**Denny Crane!** · July 25, 2014, 04:11 PM

Originally Posted by RubiconDecision

Remember that if you're using power tools on concrete that you need special masonry bits. Say you're drilling into it, without a masonry bit then the bit will dull rapidly because it's not made for concrete. Ask questions at the hardware store specific to working with concrete and skip the normal teenager working in that aisle, but go to the craftsman expert to get tips. Good luck.

Done already using a diamond tipped concrete grinding disk but thank you for the thought. I had it already for cutting into walls and pointing.

**~~RubiconDecision~~** · July 25, 2014, 04:23 PM

Good for you for knowing to do that, and for repairing something yourself. A lot of guys now-a-days simply hire someone and things guys used to do themselves are being lost. The art of being manly and repairing your own home or car is being lost.

Concrete need expansion joints too because of the ground settling, something to be taken into consideration otherwise it'll crack.

**Denny Crane!** · July 25, 2014, 04:30 PM

Originally Posted by RubiconDecision

Good for you for knowing to do that, and for repairing something yourself. A lot of guys now-a-days simply hire someone and things guys used to do themselves are being lost. The art of being manly and repairing your own home or car is being lost.

About a year ago I started retraining, almost any spare moment reading and 2 different courses (start a third 12 month one soon) to the point I've now gone self employed as a plasterer while continuing to train. Very limited knowledge on concrete though as Ive mainly been doing interior work.

Recently though I'm renovating two houses as I think I said earlier. One of which has been from joists to ceilings but this one:

The steps run up the side there, about 30-40 ft of them.

Has an awful lot of outside work to be done. Can't be seen clearly but just in the middle there is a giant great big pond fed from a stream and a beautiful mini pond with a nice slate waterfall. Loads of potential but terribly done.

And then more concrete work (total rebuild)

It's a family home so its all getting done by me, rather not pay for any work to be done except rewiring of course, that's done.

**~~RubiconDecision~~** · July 25, 2014, 04:51 PM

Nicely done and the real stone walls look great too. I'd always done work around the house as a kid because we were too poor to afford a craftsman to repair things, but when I got married, my head was buried in a book on fixing the endless honey-dos that my wife would notice needed to be done. 'Saved a lot of money, and learned how to fix appliances too.

Some guys can't replace a light switch. Others can completely rebuild steps. Which is better? It's rather obvious and gives you a sense of pride.