Soon after my wife and I installed a patio in our back yard,the concrete foundation in our 85-year-old house started coming off in chunks, just where the pavers abut it. I am thinking there’s some kind of chemical reaction going on here. There is no standing water. Any suggestions?
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Replies
Dude, thats whacked!
You have water splashing from above? freeze thaw cycles?
maybe someone here can make sense, but I don't recall hearing of a Chem reaction..I think ya have a water issue.
Spheramid Enterprises Architectural Woodworks
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Thanks for your reply! No water issues that I can possibly imagine. Yes on the freeze/thaw cycles, being here in the Finger Lakes of NY, but in that case the flaking would happen in other parts of the foundation. It is exclusively where we installed the concrete pavers.
do you salt that walkway?
BTW, we do like smaller photos, not screen size, but KB's If you use a resizer like IRFANVIEW and save the Photo as 400x600 some of the troglodytes on dial up can partake in your query.
Iview is a free download, and easy as pie to use. A quick google on it will get you to the download site, IIRC it is Tucows or similar.Spheramid Enterprises Architectural Woodworks
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Imagine snow drifted (or shoveled) against the foundation wall. Melts from the lost heat of the foundation,days sun, water seeps into the concrete , freezes when the temps drop again. It sure appears to me that you are suffering from a freeze/thaw cycle acting on old concrete that is water saturated. Any salt would make the situation worse.
They can't get your Goat if you don't tell them where it is hidden.
Yep, and maybe a less than ideal mix of crete..the spalling is severe.Spheramid Enterprises Architectural Woodworks
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Damn !! I just went back and looked at the photo's again.. Notice the dryer vent.
Damage is directly below and to the sides of it.
Bet the patio slopes down to the left from the window in the first picture. Water melts under the vent, runs along the pavers and against the house, re-freezes.
They can't get your Goat if you don't tell them where it is hidden.
I'm thinkin' the new patio has covered up a natural water wicking/draining environment. What water used to drain away, is now being trapped and migrating up into his walls.
Or - a new roof leak / ice dam has created a new stream of water entering behind the siding.
We need a full picture of this side of the house so we can see his eaves as well as a landscape shot showing slope.
""I'm thinkin' the new patio has covered up a natural water wicking/draining environment. What water used to drain away, is now being trapped and migrating up into his walls."' I agree. He changed the drainage pattern.
They can't get your Goat if you don't tell them where it is hidden.
Thanks everybody! You've got me thinking! Sorry about the size of the photos. I put a huge slope on the patio (3" over 8 feet) but perhaps snow gets backed against the wall and seeps into the concrete before it can melt away.I don't use salt and almost never use the dryer.
Edited 3/15/2009 11:52 am ET by Flapjack66
You may also have roof drainage splashing up against the foundation.. That concrete is getting saturated somehow and the freeze thaw is popping it off.
They can't get your Goat if you don't tell them where it is hidden.
As tennesee tuxedo says..." well, Chumley...."
He says dryer sees infrequent use, little or no salt, almost 1/2" per foot of slope away..it has to be a gutter issue..I'd bet it's boiling over and splash freezeing.
I'd check the downspout leaders first off.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
I'll get back to you in another half hour or so when those monster photos finish downloading. Meanwhile,I'll go get the firewood brought in.
No need for photos sized larger than 200KBs
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When you gonna spring for Wildblue? You'd smack yerself for waiting once ya use it for a minute. It wasn't available here till last year or so, but man..once ya get dialed in and no severe weather..yoube a happy camper.Spheramid Enterprises Architectural Woodworks
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DW and I have talked it over and probably will do soon. I know there will be times out of service from storms, but this slow waiting is getting to me after having used some high speed.
She is likely to be taking a class online which would require a high speed connection. She is going to the mainland now every Sun PM thru Monday AM for a 12 hr class on Mondays to get boned up on things for re-entry to the job market in the medical field.I was on the way out anyways or I would have never even tried that large file on two pictures. I still had to scroll all over the screen to see things.
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I open in RT click, new window, and XP resizes the pic. That he posted took maybe 15 seconds for the MIDDLE speed Sat that I have.
Weather is the biggie, I lose the signal yet the TV will still have joojoo...the INTernet is is more delicate..I'm in the ground with a pole, vibrations would be badder...but really, its the bomb.Spheramid Enterprises Architectural Woodworks
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I forgot my Firefox has a button to click to limit to frame size display.we've had plenty problems with the TV sat because the geosynch sats are way downm over Mexico more or less. That puts them mighty low on the horizon from up in Maine. I had to get teh dish all the way up on the gable end about 26 feet and then cut down a lot of trees. Then every spring, when new shoots leave out and limbs grow two feet in a week or so, I have to do more trimmming to keep a signal.We are in a bit of a hole here - a big spoon so not even regular TV and no cell reception.One advantage is that a nuke heat blastwash might run over us unless it came from a 15° portion of the horizon, LOL
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View Image
When you can see the whole picture at one time like that, it gets easier to view and see stuff instead of one pixel at a time, LOL.Sure makes it look like that hose bibb is leaking and splashing there
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OK, back in for lunch.
If there is any chemical problems there, it could easily have come from the eighty years of life and various sprays for insects, fertilizers, salts, etc. That long ago, it was not uncommon to have unwashed sand with impurities for the mix either.
But the main immediate problem is definitely from water/ice. Before the patio, water could drain and perk in to the soil more easily. Now it splashes up against what is possibly a minimal strength concrete foundation. Keeping it wet in freeze/that cycles is causing what you see. Also there is a puddle of water from that hose bibb showing, so there is more water accumulation than you recall, it appears.
Take up the row of pacers set close to, clean and repair with one of the mortar patch products when it warms up, seal it and reset the pavers. Meanwhile, do all you can to prevent water from lying on that surface.
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"Meanwhile, do all you can to prevent water from lying on that surface."
Yeah!! Right on!! The truth or nothing! Accept NO LIES. damm water..Spheramid Enterprises Architectural Woodworks
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Well...
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Does that faucet have a drip?http://www.tvwsolar.com
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I believe it does, and the dryer vent sends out more moisture than he thinks. most of the white efflorescence is right there at the dryer dump.I also studied these more. See a lot of stains from leaves on this crete and you can see some drifted up in the back corner. Could likely have been even more there in the snow all winter holding moisture.Whatever the source, it is plain from that efflorescence and the way the surface popped that he has a water problem. Since it is only causing the symptom just at the new patio, and just since it was installed, the patio has to be causing or amplifying the water problem somehow.
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I'm wondering if frost heave could play a part as well - the pavers look like they're butted up against the house pretty tight. I've seen it happen w/ concrete porch steps, where they'll rise as the soil freezes and grind up against the porch slab, spalling off a vertical outer layer of concrete. Once that's gone, it wouldn't take long for more water to get up under there and pop off the top as well.
Dunno if that makes sense, but it's my $0.02.
That would look much different. I know what you mean - when a slab lifts and takes adjacent material with it.The outer edge of the tiles would be out of place, lifted a bit. A tile has not the power lifting with heaves that a whole slab leverage has.
The concrete chipped off would look like flaked chips instead of exploded out in smaller pieces crumbled up, and there would not be the efflorescence
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"Soon after my wife and I installed a patio in our back yard,the concrete foundation in our 85-year-old house started coming off "
So by definition it's related to the patio.
Did you by any chance notice any weep holes in the brick? Remember - brick isn't waterproof, and getting dampness out of it nearly always involves weep holes somewhere.
Also, did you put a plastic vapor barrier under the patio? Did you create a drainage plane (minimum 4"-6" crushed stone beneath the concrete? Is it possible that the plastic is 'damming' up water in the wall? If there's no drainage plane (crushed stone) under the patio concrete you have your answer, I think.
Jeff
Edited 3/15/2009 11:46 pm ET by Jeff_Clarke
I as assuming based on age of house and appearance in photos that the brick above grade was three brick thick solid.Do they use weeps in that type wall too? I don't think i've ever seen that, only in brck veneer
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No weep holes. No plastic under the pavers, but 5" of gravel under 2" of sand. The gutters above this section are good, so there's no water coming off the roof. Reading everyone's posts, it seems like snow plus freeze/thaw cycles are doing it. Next question, how to repair?
Well there is repair and there is prevent . There are all sorts of concrete patching mixes available.
Wash the surface, wire brush , use the repair material of your choice and seal it after it cures out. Most patch materials contain an adhesive or bonding agent. Now to prevent I would lift that paver closest to the house out. Put a small planting bed in there or cut the pavers a couple of inches shy of the house foundation and fill the area with sand.
They can't get your Goat if you don't tell them where it is hidden.
I'd pull pavers to that hose bib, trench and lay a solid pvc drain pipe/surface drain system so's that bib naturally drips into it and away. I'm thinkin it would take away any other water wanting to accumulate there.
A cure for the water against the building foundation must be effected or he will be repairing that foundation forever no doubt about that.. Best method to achieve that it is open to discussion.
They can't get your Goat if you don't tell them where it is hidden.
Alright then.
I'd take out two or three rows of pavers against the house. Trench down to the frost level. Power wash and scrub the foundation.
Above grade, I'd repair the broken and cracked off concrete with this:
http://www.miracote.com/index.php?href=productdetail&id=19 A few 'poxied pins into the old material would be nice. I'd shape that to pretty near match the profiles of the existing.
Then, to match the color, I'd top it with this, after getting the color mix down pat:
http://www.miracote.com/index.php?href=productdetail&id=16 I'd expect to play artist for awhile, getting my textures and tints just right.
And then, Xypex, hydralic ceement, roofing tar, some dang thing to better seal below grade
While I had the hole open, that aforementioned drain would go back in on the way out.
You guys are fantastic! Thanks everyone! I will get right on it.
Wait until it warms up before you do it.
Ok. That'll be, like, in 2 months around here. I got time.
Today was nice!
I think there is some circumstantial evidence
here. That amount of spalling all the sudden? That seldom used dryer vent is 16" above the curb? I think an old problem has been been made worse.
Notice the brick joints are near perfect (even thou they were
never tucked well). Yet the concrete is failing right next door. Bad mix, coupled with water and or salt.
An awful lot of caulk on that window. Long term water problem.