What’s going on with this exterior wall and how do I fix it?
This photo shows a section of an exterior wall of my 1870s Victorian located in Beacon, NY. The house sits on the side of a fairly steep hill; this part of the house is actually the downhill side.
Every spring the wall opposite this one (on the uphill side) takes on water that trickles into the basement; most of the water evaporates before it hits the ground. I plan to address the Yankee gutters this spring and, most importantly, pitch the ground significantly away from the house.
This side, while damp, doesn’t leach water at all. The brick above grade is painted on the outside with what I’m assuming is latex paint. It’s flaking in many areas.
I’m wondering what’s causing the color variations along this wall? And is there any way to fix / seal it?
Thanks,
Chris
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Chris, your photo did not come through.
The white is efflorescence from the rain water splashing on the ground outside against the brick. The black is rising damp and has mold and minerals from the soil involved.
To fix it would involve remedying the water problems, functioning gutters and foundation drains. Probably some form of exterior foam insulation and waterproofing.
You could also manage the water from the inside with dimple mat and a perimeter trench drain to a sump pump which would at least control the moisture moving into the interior of the home but would allow the brick and mortar to continue to deteriorate.
As with all things in a quantum universe, this wall was probabilistically perfect until you observed it, and then it resolved into a manifestation of your fears. I would recommend a good Jungian therapist to fix this problem.
Judging from the age of the house I would guess the discoloration at the bottom is partly to blame from "rising damp." Staying damp has caused mineral and mold stains. I have never performed a fix for such a condition but I have been told a moisture barrier must be put into place along the horizontal plane between the footer and the brick to stop the capillary action which is what causes the rising damp, Treating the brick with silicone is often suggested but in my opinion is absolutely the wrong thing to do since it can make matters worse. Mr. Chandler's advice as far as additional measures to keep the water off the walls is the next step but first you must find the source of the water intrusion and remedy that before proceeding further. The Salts left behind in the masonry will continue to absorb moisture from the air even if the original sources have been removed. There are products on the market designed to remove the salts. Failure to remove these salts will only prevent a proper paint bond should you decide to replace the old peeling paint.
The rising damp condition must be treated and remedied first however. Providing a DPC or damp proofing course is probably the best solution overall.
I'm not the expert on this but I have seen lots of houses with this condition.
I'm thinking you need Robert Riversong's advice more than mine. But I had a quasi similar issue here in Minneapolis and a few things might be helpful. Our project had a 100 year old limestone rubble foundation with a huge Victorian mass of walls/floors above. The Foundation was beginning to fail, there was efflorescence and some mold on the inside. The black/grey below the above efflorescence/spalling (ES) above is likely mold which exists here cause there as the bricks are likely more in tact therefore their surfaces can catch/hold dusts with the cellulosic content needed for mold growth. You would have mold above that but the ES above that is grinding away the brick surface and cellulose so mold likely is in the debris on the floor?
For our project, Diverting exterior water was crucial step 1. Then determining whether the foundation even had enough strength remaining to warrant a repair (some might need full replacement). Also, how bad is water damage to the sole plate (if one) or the joists sitting on the foundation? We then repaired, water-proofed and insulated the exterior foundation. We installed temp beams under floor joists near foundation in basement so that not all the house weight was on the foundation. Then excavated one side of foundation at a time (careful...may need to brace the opposite foundation). Cleaned the foundation, repaired the damaged locations, sprayed water proofing membrane and then 3" of closed cell urethane foam. We hope the foam acts as a buffer for hydrostatic pressures thus protecting the water proofing and the masonry. It also keeps that inside foundation wall much closer to the temp of the basement thus reducing likelihood of interior moisture condensing on the surface which can also cause mold. Also, we setup an exterior drain tile in case our exterior water diversion wasn't 100%. Oh, and for foundation part above grade we added stucco mesh + parge coat + elastomeric stucco finish that is vapor permeable. Interior wall face received stucco mesh and parge coat and may someday get that elastomeric stucco coating. The basement is so much warmer (Fall-Spring) and drier that the client now uses that space for an office. The blower door tech was amazed at the tightness of the foundation. Minor review of our plans by the structural engineer was needed and then some courage to dive in....oh, and tens of thousands of dollars were needed as well. Best wishes on finding a good therapist.
Now comes the hindsight benefits as I'm sure someone will reply to this with something that leave me wondering if we did the right thing!
Yes to the efflorescence. The water need not splash up the wall, however; it can travel up the bricks by capillarity.
More water is absorbed by the soil near the surface than further down. Although all the soil is damp to a degree, the hydrostatic pressure decreases with depth, and thus the visible salts on the surface decrease in concentration on the lower bricks. Closer examination with a hand lens would probably reveal the presence of salts on the bricks that are darker in color.
The black area is most likely surface mold that gets the moisture necessary to grow from condensation when the lowest and therefore the coldest section of the wall falls below dew point.
I agree with the efflorescence above / mold below explanation; moisture from the ground is responsible for both. Bob Alf has the best description of the necessary solution: direct surface water away from the house, waterproof the outside surface of the foundation (insulating it as well is a good idea as long as you've got it exposed), and providing a foundation drain (perforated pipe in gravel backfill) to move water away from the house. The best type of waterproofing, the best foundation drain, and the best way of disposing of the water collected by the foundation drain will be the next questions, and will depend on your individual situation. An architect or engineer familiar with this kind of problem is advisable, and a contractor experience with this kind of work is essential.
Riversong has a point, but if all this is really beyond your budget I would advise against the Jungian therapist and instead find a bartender with a PhD in quantum physics. Schroedinger would have kittens....
Chris,
I believe the white that you see along the grade level of the brick is efflorescence or lime deposits from the mortar. The grey area could be from deteriorated clay drainpipe, if they even used that system back then, or there could have been a flood. It is difficult to say but I would research the history of the house to get more information on this.
Mike Thomas,
Your high order of wit is an asset to the site. Thanks!
I agree with Mike Thomas' evaluation. We are currently working on a project that has an unfinished basement that was never waterproofed properly and there is similiar markings on the exposed block. There is one course on the exterior that is above grade and was painted with latex. After excavating down to the footings we spray Watchdog (asphalt emulsion waterproofing product) and Aquadrain 15X (polypropylene dimple core w/non-woven polypropylene filter fabric on one side) to protect it. After backfilling we injected ccSPF foam into the block cavities that were never insulated, 3/4" XPS glued to the interior block with 2x2 furring strips to accomodate electrical outlets. We have also used this approach (Watchdog/Aquadrain 15X) on a house with brick veneer where we conditoned the crawlspace who's grade was lower than the exterior grade. It worked beautifully. Either way (exposed block/brick veneer) you have to use the perimeter drain. We use a product called EZ Drain and it's just a 4" perforated pipe encapsulated with packing peanuts and netting. No more shoveling #57 stone! We've got better things to do like visiting our friend at the local tavern who is an unemployed astrophysicists moonlighting as a bartender!
Is there a foundation or is the brick on soil? Either way the worse case is that you are going to have to do all the water diversion work (and look for flows outside from other houses to yours) then (and take a deep breath) underpin the wall by employing a fully insured masonry underpinning specialist to very very carefully take out short sections of the brick wall, lay a new foundation in short sections and build a new brickwall up to the level of stable and sound bricks or to the course of header bricks just below the window.
The need for the underpinning work is related to the condition of those bricks resting on the soil/foundation and the condition of the foundation.
Michael Chandler wrote / ...at least control the moisture moving into the interior of the home but would allow the brick and mortar to continue to deteriorate./ Allow the brick and mortar to continue to deteriorate ... YIKES!
Also I wouldn t be too happy with allowing the other wall to be damp.
I worked on a west-coast project a few decades ago - high rise with several floors of underground parking. Excavation was about 40' deep and kept caving in before proper external waterproofing/damproofing could be applied.
We used a product called VANDEX - http://www.vandex.com - applied to inside of the concrete walls that crystalizes as it follows the moisture back out of the wall. Damp walls before - dry after. Not sure if Vandex has a product that could be used for brick/block but it might be worth a call. Assuming the bricks are sound after 140 years I woudln't panic about the foundation falling in any time soon - but getting the surface water directed well away from all sides of the foundation should be a key focus -
To confirm if the paint is latex or oil based - dab it with some fingernail polish remover - if it orange peels it is oil based. if not - probably latex. Latex paint ususally "breathes" better than oil base so it must be on pretty thick to peel if it is latex. In any case, all loose exterior coating should be removed down to sound brick before any new topcoat is applied.
Along with the spirits and therapists already suggested- I will add: Good Luck!!
I would like to know if there were any water or damp occuring in beginning of this building comleted?
I think the wet or damp comes from dew condensation when wet air exceeds dew point.
My way of remedy will be an insulation and air tight to stop the wet air to meet warm air.
Jeffrey from Taiwan
Whoa, there, rein in those wild horses!
What I see in that picture (outside of subconscious archetypes) is a perfectly sound basement wall. No need to spend $50,000 replacing it just yet.
Start by diverting the water at the source: gutters, downspouts, leaders or subsurface drains to move the water at least 10' from the house, and good grading at 5% with swales or French drains as necessary. Every inch of rainfall puts more than 500 gallons of water under the eaves of a typical house. Divert that water and you may have solved your moisture problems.
If there is a window well outside that basement window, cap it with a plexiglass cover or find some other way to keep water and debris out.
I would also install a ground vapor barrier and rat slab on the floor to keep ground moisture (and radon gas) out of the conditioned space. If the basement humidity remains high, then a dehumidifier or some heat would be in order.
Shrodinger's kittens may be decoherent with their observer-entangled mother cat, but this wall seems perfectly coherent, which makes some of the radical suggestions incoherent (or non-complementary, as Niels Bohr might say).
"Assuming the bricks are sound after 140 years I wouldn't panic about the foundation falling in any time soon - but getting the surface water directed well away from all sides of the foundation should be a key focus" - D. Dixon
Amen to that. Get the water away from the basement wall. If the brick is sound with no major cracks don't mess with underpinning unless you are changing the interior grade condition, e.g. to finish the basement. In a house this age I'm sure there are far more rewarding places to spend tens of thousands of dollars.
By the way, efflorescence does not damage brickwork or blockwork other than superficially. The moisture that causes efflorescence may also cause structural damage to brickwork, most often by freeze/thaw spalling, but I see no evidence of that here. Though it can continue for years efflorescence is a temporary condition - sooner or later all the mineral salts contained in the brick will be driven out, even though the moisture problem may remain. Efflorescence is the canary in the coalmine, not the poison gas.
I'd also question the excavate/waterproof/foundation drain approach. It may seem like the thorough and responsible thing to do but in many cases it may be unnecessary or even harmful. Essentially you are removing a century's worth of dense compacted soil and replacing it with less-compacted and more porous material. Any subsurface perforated drain will eventually become clogged with fine particulate material brought down by the moisture, it's only a matter of time. Unless of course you do the surface grading properly - in which case the drain serves no purpose.
Thanks, everyone for your input. I'm going to address the grade and gutter issues as a start. The ground actually pitches toward the part of the wall that takes on the most water. It's an obvious fix and I've known that I need to address it for a while. But in order for me to spread all of that dirt I have to get my better half to move all of the bushes and shrubs she's very attached to (not attached in an unhealthy way, Robert - so I don't think she'll need to join me in psychoanalysis).
I was originally thinking of adding "ground gutters" around the house (a couple of feet of EPDM attached to the foundation a few feet below the ground), but that seems a bit much at this point. I do think working out the grading issues will make the difference (and fixing gutters as needed).
I'm wondering about running the gutters into 4-in. pvc (with holes) that will sit a foot or so below grade (holes facing up, pitched to daylight in our backyard which is a long, steep lot). I'd then cover the drain around the perimeter with pea gravel. Does this seem like a good idea?
No, Chris, that's not a good idea. Subsurface drains to daylight for roof gutters is the ideal rain removal system. But the purpose is to prevent that 500 gallons/inch of rain from getting into the ground around the foundation. Perforated pipe will only put it right back into the ground. Solid pipe is what is called for.
spray foam