Basement wall patch advice

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

mass_burner

Minister of Fire
Sep 24, 2013
2,645
SE Mass
I need to patch two spots in my basement wall. The first is around the main sewer pipe exit; the second is on the opposite wall to a long existing crack that seeps water. I plan on using hydrolic cement. My first question:

1. Any special about patching around a copper pipe?
2. Am I about to use the right patch?

I'll post some pics later.
 
correct product, will seal great.
on the copper I would use something to stop direct contact, might cause an electrolysis situation and corrode. rubber hose slit and slide around?
 
If it's a serious issue that you want fixed right. I've always used a guy that does a two part epoxy system.

He drills into the crack and inserts injection "straws" every 6-10", then fills them with this stuff and it's done. First thing he always does is swear at the previous messes people made with hydrolic cement.

Carries a 10 year warranty, isn't crazy expensive, and it works. Of course he's in NH and I gave his last card away, but I'd look for someone local to you who has the same type of set up.

If it's not a bad leak and won't ruin anything if it leaks again. Try the hydrolic cement, you may want to chisel is open a bit to allow enough cement to get in there and grab as it expands otherwise it may all just push out to the surface.

not sure about using it around copper, I would do some research first. (May react with the metal)
 
I think you have poured walls???

if he has a copper main, his house is old enough it is probably block.
 
Epoxy for poured walls. Yes.
Me, half my foundation is poured, 1/2 is stone, floor is 3/4" stone over dirt no vapor barrier. :mad:

But, it's solid. ==c
 
Tricks to using hydraulic cement properly when patching cracks;
Chisel the entire crack to 1/2" x1/2" minimum. Make the bottom of the cut wider than the top, a locking key.
Wet the inside of the crack first to prevent the water from being mechanically drawn from the mix before chemical setup.
Mix thick enough to work vertical. Consistency of peanut butter is appropriate.
If it is too wet the only solution is to thicken with more product. Mix fast, working time is limited.
A square trowel is better for this task than a pointed one. A stiff putty knife is good too.
I mix in a small metal plaster tray, it is the right size and convenient. A bread pan is also a good size.
Mix small batches, you may have as little as 5 minutes working time.
Work the mix into the cracks with a pressing action. Take your time, quality is important here.
Cleanup is easiest with a damp mason's sponge and several buckets of clean water. Keep rotating the sponge so you only ever work on a clean surface of the sponge.
Cleanup should begin shortly after setup is achieved but be gentle and use a damp but NOT wet sponge.

Coat the copper pipe with roofing tar if it will contact cement. allow the tar to set before applying cement.
Or, if you can, wrap it with tar paper and tape it up outside the wall. (inside the basement) Be neat and you can trim the excess paper off after the cement sets and is cleaned up.

Mask off things you don't want cement on, but if you mess up, wipe it up with your damp sponge fast. If not, a wire brush will eat it away.

Nothing wrong with using an air chisel to prep if you have one handy or even a diamond wheel on a side grinder if you are not skilled with a cold chisel and drill hammer.

Again angle your cuts so the inside of the crack has the shape of the bottom half of a pyramid, with the opening narrow. This is the trick to a successful repair.
 
Pics
uploadfromtaptalk1426035123990.jpg
uploadfromtaptalk1426035172946.jpg
uploadfromtaptalk1426035186881.jpg
 
For that small of a hole I'd probably fill it with backer and silicone. Quality silicone is rated for 50years. I'd put a liberal coat of silicone over the concrete, let it dry, then fill the remaining spa ce with a mix of silicone and copper mesh. Cover it with more silicone.
 
For that small of a hole I'd probably fill it with backer and silicone. Quality silicone is rated for 50years. I'd put a liberal coat of silicone over the concrete, let it dry, then fill the remaining spa ce with a mix of silicone and copper mesh. Cover it with more silicone.

Looks like a 3" copper drain line, which would make the hole 6-8" across.

With the wye fitting there, a brush on coating such as the roofing tar before packing mortar in would be the only option. Mix the mortar thick otherwise it will sag before it cures. Might also consider using a very weak mortar mix such as N or even O so that it is easily removable without damaging the pipe should you ever need to do any repairs.
 
Looks like a 3" copper drain line, which would make the hole 6-8" across.

With the wye fitting there, a brush on coating such as the roofing tar before packing mortar in would be the only option. Mix the mortar thick otherwise it will sag before it cures. Might also consider using a very weak mortar mix such as N or even O so that it is easily removable without damaging the pipe should you ever need to do any repairs.
It could be 3" but the code is 4" through the wall and out 10 feet (plumbers only go out ten feet. Then the septic licensed guys take over)
Not that it matters.
Yes, painted with roofing tar, but the patch should be hydraulic cement. Regular mortar isn't waterproof especially if pressure starts building up.
 
It could be 3" but the code is 4" through the wall and out 10 feet (plumbers only go out ten feet. Then the septic licensed guys take over)
Not that it matters.
Yes, painted with roofing tar, but the patch should be hydraulic cement. Regular mortar isn't waterproof especially if pressure starts building up.

Isn't the typical hydraulic cement 5000+ psi? I've ran into it plenty of times repointing stone foundations and hate it when I find it, the stuff is so hard its impossible to break out even if loose already. I'd be afraid that any future repair to or around that wye, if hydraulic cement were used, would require destroying the fitting to get the access hole opened back up.

Standard mortar definitely has a higher chance of seeping, for sure.
 
Isn't the typical hydraulic cement 5000+ psi? I've ran into it plenty of times repointing stone foundations and hate it when I find it, the stuff is so hard its impossible to break out even if loose already. I'd be afraid that any future repair to or around that wye, if hydraulic cement were used, would require destroying the fitting to get the access hole opened back up.

Standard mortar definitely has a higher chance of seeping, for sure.
Yes it can be 10,000 if it is the best stuff and mixed perfectly and the installed correctly. Carbide tipped bits go right through it though.
Drill a series of holes, even if only a 1/4" diameter The thing is though as long the end clean out (ECO) stays exposed, you just thread an adapter into that, then another tee wye, another end clean out. No reason the tee should have to come out.
 
Last edited:
It could be 3" but the code is 4" through the wall and out 10 feet (plumbers only go out ten feet. Then the septic licensed guys take over)
Not that it matters.
Yes, painted with roofing tar, but the patch should be hydraulic cement. Regular mortar isn't waterproof especially if pressure starts building up.
The house was built in '56. This is original pipe.
 
Yes, 6x8 sounds right. About 3-4" deep, it also has soil at the rear in some spots.
 
The house was built in '56. This is original pipe.
If it ever has to be replaced it will have to be increased to 4" anyway. Copper drain pipes usually last a very long time and the old ones like yours are thick pipes with cast brass fittings, very durable. These days we cast a six inch PVC pipe in the wall, then run a 1" thick O-ring over the four inch pipe, but either way, you want it sealed.
If it ever did have to come out though, for old work we drill a 6" hole through the wall with a core drill and still use the O-ring.
 
I called over a mason I know and he says it was left open when the foundation was poured. He recommends a foam filler that can be removed easily if necessary. There was a sandy "semi permanent" filler in there, that's why it leaked after so many years.
 
The other crack is not so easy. Turns out the crack goes through to the outside. The seeping starts about 4' under ground. Repair is necessary on both sides. ~$1200.
 
I call bull pucky, call some one else. they can drill from the inside and power inject epoxy into the crack. I have seen it done many times.
 
  • Like
Reactions: Dune and Warm_in_NH
My brother used hydraulic cement to fix a couple of foundation leaks in a home we own in NH. As with anything the key to success is follow the product directions to the letter! In our case the real underlying issue was crummy foundation drainage (roof shed pouring down onto an area with insufficient foundation drainage). The area was excavated, proper drainage pipe and the necessary crushed stone was installed and the "fix" was done and is now ready for the ages.

My late FIL was all about drainage. At the time I was clueless about how important "that stuff" was. But in all the years hence my admiration for his dogged attention to drainage has increased exponentially! Trust me, all you have to do is excavate a foundation to put in what should've been in place upon construction to appreciate how fundamentally important drainage can be!
 
I call bull pucky, call some one else. they can drill from the inside and power inject epoxy into the crack. I have seen it done many times.
So this is another way to do it? Is this way more expensive?
 
it is the way it is done here, in Ohio. not sure of cost. they come in, drill some holes along the crack and inject epoxy which fills and seals the crack. I would think it would be cheaper than having to expose the outside to seal it. the ones I have seen done took an hour or less.
 
it is the way it is done here, in Ohio. not sure of cost. they come in, drill some holes along the crack and inject epoxy which fills and seals the crack. I would think it would be cheaper than having to expose the outside to seal it. the ones I have seen done took an hour or less.
So with this process, there's no need to seal the outside?
 
Status
Not open for further replies.