What to Expect with Basement Waterproofing

Leave a Comment - 26



Subject: WaterProofing Solutions

The inspection you carried out and the solutions you provided was nearly perfect. I have experienced the same and was so dangerous. There were all water over the basement, and because of that the electricity was cut off, then we approached to Raja n Raja - one of the unbeatable waterproofing solution provider in our town.
Then what our problem was solved within hours.
Thanks to them...


Subject: waterproofing solid stone basement

Have a home built @1955. 18" think solid stone walls (Avondale brown fieldstone, no concrete block), all the way to the footers, with parge on the inside walls. Exceedingly well constructed. Problem is that moisture bubbles up paint/finish on inside walls. No standing water or wetness other than the bubbling. Plan to remodel basement and think that outside waterproofing is the better way to go. Local waterproofing contractor recently visited for estimate purposes and said that they would not guarantee such work. Does that make sense? Would appreciate any suggestions and pointers, particularly on cost. Many thanks.

Daniel Thomas

Subject: Brick foundation

You need to excavate entire house. Pargeing entire footing. Let dry. Tar. Let dry. Clean gravel bed all around to come level with bottom of footing. Than perforated weeper with sock all around and connections running vertical under basement windows if any. Then more clean gravel covering entire thing. And 15 foot trench with catch basin filled with gravel to carry water away. Then wrap entire footings in dimple membrane. If you life up north then you can add ridged insulation as well. Then back fill and enjoy 100+ years of dry basement.


Subject: water issues

Bought house in January, had a mold issue in the basement which was finished at the time, Mold contractor tore stripped all drywall and studding out of the basement (1500 sqft rancher built in 1973 with full basement by the way) They grey painted the floor and white painted the block wall (not waterproof, just a future mold mitigation thing. I did note that the majority of the mold grew around 2 windows which are glass slatted vents. I assume these are leaking. just ordered hopper vents today. house was vacant for over a year and gutters were completely clogged. They are completely clear now and drain away from foundation.

Grading is a problem in the back of the house (also the side the house where the problem windows are). I am in process of digging a swale 12' away from the house and grading out to it. Already demolished a negatively slopped sidewalk in the back.

Yesterday it poured like crazy but i was not home. Looking at the basement wall at the back yard from inside, it looks "blotchy" in spots like it is wet, because it is. There is a puddle in the floor, and there is so much moisture in the air the it is condensating on the plumbing and dripping off. After heavy rains I have also noticed it wet at minor cracks in the slab floor. A dehumidifier runs and I just hooked a hose to it dump into the sump so it will run continuous. The basement floor has a 1" gap between the block wall and the floor continuous, and i can see dimpled sheeting in some sections. in the sump pit there is drain tile that drains into it from the outside, i believe this to be a french because it will trickle water even when it hasn't rained for a week.

Lastly, I don't believe the block wall is filling with water because it has holes 18"-24" up from the floor where whoever finished it before punched in spots to allow depth for outlets instead of building their wall out 2 more inches. It also has minor cracks in mortar joints. but then water is soaking in through the blocks.

My question is, after the grade is fixed, what would be the best solution for my situation for a more permanent solution? I was looking to Drylock but I've read that is not good for hydrostatic pressure on block walls.



Subject: Wet basement; wet crawlspace; wet garage

Entry to front door is one step up. 5 below grade vents are along the front of the house but not in front of the garage (concrete slab) that is entered from back of house. When facing the house, the left side has about 18" of crawl space underneath and the right side of the house is higher (the part basement and part crawlspace side) with about 7 steps to enter the right side of the house and the same number of steps on that same side of the house at the back entrance. the garage side of the house gets lower again with 4 steps to the garage but once in the garage, only 2 steps to floor level. House built in 1950s. Parents placed a sump pump (the exterior steps to basement allows water to drain downward toward the pump despite the roofing over the steps) at the entry door and some type of dark grey concrete coating was placed halfway up on the block walls throughout the basement. All efforts worked only temporarily. Today, most of the water seems to be coming in on the opposite side to the pump and is downhill so does not reach the pump unless the entire floor is covered and then it only pumps what is in the vicinity of the pump. Also if enough water gets into the crawl space, water pours like a water fall through stair step cracks between the blocks under the crawl space door. This did not occur frequently but certainly when it rains very hard for a long period of time. After the devastating SC flood this past Oct., I seem to have to pump water every time it rains now. All of the solutions I've gotten for the problems make my head spin. Don't know what advice to follow but have replaced gutters which has made things worse in some ways. The downspouts are extended out 4 feet or so on only 2 at the front of the house and it just pools more water in those areas which can't be good. The supposed seamless gutters drip water on my head when I try to enter the house at the door on the steps. I believe that the below grade vents are a contributing factor as well as the cracks under the crawlspace door that opens to the basement, not to mention those gutters. Sometimes water seems to be coming up or draining from the sides of the sump pump hole and there is a mysterious pipe along the side of the wall that also drops water into the basement when it rains. I think perhaps a washer was once located there. There are faucets above as well. No one seems to know where that pipe leads but I know that water is getting to it and through it somehow. A few days ago (another estimate) I was shown rust stained area at the base of the walls, sort of looks like a baseboard and was told that groundwater was coming in there. There are things in the basement that have rusted as the amount of water in the basement with the pump working during the flood took some while to be pumped out. On the opposite side of the wall with the stain is crawlspace that seems to be dig out into a basin. Perhaps that was done to accept a heating duct that extends from the furnace that is also in the basement. The window side of the basement seems to have no problems at all though the bottom of the window is flush with the ground. I can't see doing exterior excavation when it seems as though it's the interior walls are involved and of course the crawlspace. My thoughts, being on a budget, would be getting the gutters to work properly, doing something with the below grade vents but is it safe to close them up since ventilation is needed, sealing the cracks under crawlspace door, doing something with that pipe and the doorway. I think all of the water (95%) comes from the two walls that touch crawlspace. I think I can deal with the garage if I can solve the other problems. Any advice or suggestions?


Subject: damp wall / drain tile

I have slight dampness on a small area of one basement wall, somebody recommended a drain tile test, so we did that, the drain tile was determined to be functioning, but yet the guy recommended we replace the drain tile on a different wall, and install a sump pump. The yard is very low around these areas, so we're really wondering if we need to replace drain tile on a wall that is unrelated to the dampness on the one wall - even though the drain tile was determined to be functioning well? We question because we found out the guy who did the drain tile test just happens to own a foundation repair company. We don't understand why we need to replace something that seems to be functioning, and on a wall where there is no dampness / moisture?

Mark Anderson

Subject: basement waterproofing

--Steve is the only one who is posting anything about the facts on this subject. OTHER than basement back ups/floor drains, MOST basements leak/seep due to exterior cracks and other exterior openings in the foundation wall(s) or above the wall. NO interior basement system nor 20 sump pumps repair/waterproof these exterior cracks etc hence NO company who mostly or always wants to install interior systems stops water from entering, they'll never stop/prevent mold or efflorescence on walls nor do interior systems relieve/reduce ANY exterior weight/pressure against a foundation wall which causes many walls/basements to leak/seep.

Every interior system company I have met or read all of their misrepresentations on their websites etc are full of misinformation, watch out people, not kidding.

Steve Allen

Subject: Wet wall

You cannot fix a wet wall with an inside system period. Wet walls are the result of cracks and or openings on the exterior. Now you can cover the wet wall with plastic sheets on the interior of the wall. These sheets direct the water that is still going to enter to a drain under the floor, and ultimately to a sump pump. However, what do you think happens to the walls if you continually allow water to enter in order to pump it out. To me is no different than trying to fix a roof leak from the inside. I stand by my original comment. Never try and correct wall problems, cracks or dampness, from the inside.

Paul Woods

Subject: Reply to "Waterproofing"

To make an absolute judgment as to whether "never" to do negative side (inside) or positive side (outside) waterproofing, is grossly neglectful of many factors that affect which solution is appropriate.
Positive side waterproofing has the benefit of (ideally) preventing the passage of water through walls, typically by the application of a membrane, either fluid applied or sheet goods. Also, it is possible to address the exterior drain tile situation. There may be none, or the original drain tile may be clogged with silt or dirt, so new drain tile can be installed.
Unfortunately, most fluid applied waterproofing will not effectively bridge subsequent cracks that may occur. The crack bridging capabilities of the builder grade polymer products is rated to span a 1/16" crack that develops after the application. (no matter what they claim) Enhanced capabilities can be obtained by using polyurethane coatings, but the cost goes up considerably per gallon and the coverage goes down a great deal due to the viscosity of the products, so the cost rises. Also, surface preparation is critical to the performance of fluid applied products. The concrete has to be very clean and dry. Real world conditions make that very hard to accomplish, even if the weather decides to cooperate during a multi-day project. Other factors, such as poor concrete consolidation (honeycombs), form tie penetrations and a continuous cold joint at the wall-to-footing joint can make a monolithic application difficult.
Sheet goods are usually commercial grade products and use an adhesive to adhere to the wall. They are very effective if installed properly, but they're often installed incorrectly and can trap water between the membrane and wall if the top seam pulls away water enters.
With the installation of new drain tile, if the home had it when built, there will be a "sleeve" that sends the water to the inside sump. but if it wasn't installed originally, the footing has to be broken out for the sleeve and the basement floor has to be jack hammered out for the sump.
It is common for contractors to attempt to dig under the footing to accomplish this, but that creates a low point in the drainage system directly under the footing. Outside sumps must be placed below the footing, so they require a very long pipe for access and a rope or some other means to extract the pump for maintenance or replacement. (just hope it doesn't break or come undone) Also, if the home didn't have drain tile to begin with, positive side waterproofing does nothing to deal with the missing interior drain tile.
Factor in that the porch and garage walls can't be accessed without breaking out the concrete caps and excavating the fill sand to simply route the drain tile in a continuous loop and waterproof the walls.
The air conditioner must be removed and replaced, and of course, any decks, patios sidewalks or other permanent fixtures must be removed and replaced as well....
There are lots of things to consider.

With negative side waterproofing, the benefits are that no exterior excavation or concrete removal needs to be done to perform the work. Also, subsequent wall cracking is much less of an issue and in some cases, not an issue at all. A drainage system can usually be more easily installed around the entire perimeter of the house.Plastic wall panels can direct any water that enters the walls into the drainage system, and then to the sump pump. Typically, the interior drainage systems are capable of allowing a great deal of water to enter very quickly, as opposed to drain tile, which has a relatively slow water influx.
Weather isn't usually an issue when installing an interior system unless it's raining enough to cause flooding of the excavation for the drainage system. (see below)
If your basement is finished, you must remove the wall finish and any studs to install the system. If you only need the drainage material that goes in at the wall-to-floor junction, it is possible to only remove the lower part of the finish and studs. It is generally necessary to jack-hammer out the concrete floor, about 8" to 12" away from the walls to install the drainage system. After the drainage material is installed (ideally) in a bed of pea gravel, the concrete floor is repaired.
Stairways, built-in cabinets, carpet, tile, expensive trim and other considerations can be a concern when deciding to do negative side waterproofing, because they will need to be removed or altered to give access to the concrete walls and the floor beside the walls.
Typically the installation can be completed in less than half the time of exterior (positive side) waterproofing. Because negative side systems can allow moisture to enter behind the plastic wall panels, it is not uncommon for the contractor to discuss a dehumidifier, but unless there is existing organic material on the walls, no mold can grow because the plastic panels are not a food source for growth. A sump is necessary, and can be installed in an inconspicuous location, as long as there is adequate room to accommodate the discharge line which delivers the water outside. Keep in mind that the sump is in place to deal with water coming from the drainage system. Since the drainage system is continuously perforated, it doesn't matter if it's in the absolute lowest part of the floor. If you are being told that it has to be, remember that the drainage material is full of holes, and the water does not depend on the grade of the pipe. Water flows out as easily as it flows in... If you have concerns with surface water (on top of the floor), then a location in the lowest spot is a concern. Just as positive side waterproofing does nothing to deal with the inside drain tile, negative side waterproofing does not deal with the issue of exterior drain tile.
Disclaimer: I use the term "waterproofing" to describe negative side systems. Technically it is not "waterproofing" because moisture can penetrate the walls.

If you are in the unfortunate position to need your basement repaired, there is no absolutely pain free solution. You can either have your yard look like an explosion happened, and deal with the (possibly) years of adding soil to your shrinking backfill or you can rip out your walls and carpet...
I recommend (if you can find one) dealing with a contractor who can provide either solution, and doesn't have a vested interest in "selling" you on the only option he can offer. Also with either method, I highly recommend a back up sump pump that runs on alternative power in case you lose electricity. Some contractors will actually try to sell you three sump pumps that are in the same sump container. If that makes you feel better then by all means, go ahead, but the main reason they offer those is to sell more sumps. Usually two of the three are AC powered, so if you need a back-up you'll still only have the alternative powered one working anyway.

I hope this helps a little. Obviously there's much more I could add, but hopefully this covers some of the things that are important.


Subject: Waterproofing

I am in the process of trying to learn which waterproof is best for me. The entire front of my house is underground (3 to 4 ft.). After that the rest of the full basement is above ground. Built in 1950, whatever was done to waterproof the front exterior brick wall underground is long gone. The exterior wall looks and feels damp, but water does not flow out of the wall. The water that is entering the basement comes in where the exterior brick wall and slab foundation meet (a crack has developed over 65 years). The leaks form what I call little creeks that make their way to one drains in the basement. These leaks are just enough to get the bottoms of your feet. Based on the ground water table I could have 1 to 5 little creek leaks No water is coming up through the foundation. If a waterproof membrane product is applied from the interior, the water is still going to build up on the the outside of the exterior brick wall. There's no way any type of drain system was installed at the foundation 65 years ago, and I just don't get enough water to use a sump pump. Since I reside in SC, I may have the problem 5 to 7 times a year.

Steve Allen

Subject: Waterproofing

That's why clean outs are installed Waterprroofer John. Never try and fix wall issues with an interior system. The only way to correct wall moisture is to dig. The lifetime warranties in this industry do not cover wall moisture or cracking.

Paul Woods

Subject: Clean Outs?

Clean-outs in a below grade drainage system?

They would have to be installed in daylight window wells or a place where the grade allows access to the drain tile that is 7' below the grass. I've waterproofed thousands of homes and never seen a clean-out system on exterior drain tile. I have installed risers in daylight windows, but I'd hate to have to actually try to unclog a drain tile system from one of those...

If there was a clean-out, how would it be effective? Would a garden hose clean out the very small perforations in the drain tile once they've become covered with silt on the outside? If the drain tile is clogged, can you move the clog clear around to the sump sleeve or gravity drain?

Of course moisture on the walls in the form of condensation isn't covered by any warranties. It is not reasonable to expect any waterproofing system to guarantee against condensation. That's a factor of relative humidity inside the home.

Also, if cracking is an issue, then unless you install a negative side system with interior plastic wall panels, the cracking will cause problems.

No builder grade polymer membrane will bridge beyond a 1/16" subsequent crack. (no matter what the manufacturer says).

Possibly a sheet membrane or polyurethane coating would work (to a point), but if cracking is bad enough to be a concern, then the foundation or wall needs to be stabilized before waterproofing is done.

Patently saying to "never" use ANY system without knowing all the facts is irresponsible and a gross neglect of many factors that are important to consider in determining what option, whether positive side or negative side, is appropriate.

I know waterproofers who have been around for years, (or have gone under, Steve) who blindly recommend the techniques that they have used "forever" and patently dismiss any alternative system.

if anyone tries to say that only one system works in all cases, they're either just ignorant of the viable alternatives, or have a vested interest in "selling" their system. (just my opinion)

John H

Subject: combination of water origins

Trying to decide on right solution. House built in the 1950s. We have a semi finished basement (painted concrete floor, 30 linear feet of counter space, plus appliances, gas and electric stovetop, sink) in a house set on a moderate slope with mostly shale rock subsoil. Basement wall is painted cinderblock and is below ground level on all but about 15% of the foundation perimeter. We have had efflorescence and minor leaking into the basement through corners and foundation joints (where cinderblock wall meets basement floor). Over the last 6 months we have had a couple of occasions where water seems to be entering through the floor itself not just at the joints. R

Visible factors: 1) ground slopes toward house on back of structure; 2) gutters allow water to pour down along the exterior wall to ground level and hence under grade along the foundation wall. However ground water table may be another factor, so there is no assurance that fixing visible issues will do much except remove a fraction of the problem.Reluctant to do positive remediation (the prevent water from coming in strategy) because of cost and effect on exterior landscaping, stoops, A/C unit etc. but if it is the clear best shot then we would go for it. However... Since everyone who comes to assess the situation and propose a solution is invested in a specific way of doing things, it is impossible for a layman to decide between proposals.

Any thoughts, advice, appreciated.

wayne spencer

Subject: where should a sump be installed

I have very limited space in my basement . I have measured the floor to the floor joists. one side is higher than the other.should the pump be installed at the highest part of the floor or the lowest point


Subject: answer

You will want to install it at the lowest spot, water doesn't flow uphill


Subject: Which method is the best method to use for waterproofing?

My parents have a leakage problem in their basement. They need to have waterproofing done on the foundation. We had two contractors come and look at the house and give us estimates. Both had different methods for waterproofing. One method was applying blacktop to the affected area, then covering it with a layer of plastic rubber, and then adding a 1/2 inch layer of foam insulation then compacting the soil back in. The other method was building a frame around the affected area, pour 4 inch thick concrete around the foundation, apply a waterproof membrane on the set concrete, and then finish with a termination bar and caulking. We aren't sure which method is the best the method to go with. Also, the contractor for the first method only has one review online that I could find. The contractor for the second method has no reviews that I could find. Any advice you can give will be greatly appreciated. Thanks.


Subject: efflorescence

We do not have water visibly coming into the basement, but have the efflorescence that indicates the water is coming into the walls. We use a dehumidifier during damper seasons, but not during the winter. What do we do to conrrect this problem? I am very concerned about the walls. Thank you.


Subject: Interior waterproofing

I was wondering if you could give your opinion of interior waterproofing? Our basement is mildly damp in two corners. Should we spend the money to dig around our foundation and destroy our deck or is interior waterproofing acceptable? Also what do you think of wall anchors?

basement waterproofing system

Subject: I had earlier used to think

I had earlier used to think that leaking of water is a normal problem which worsens during monsoons, but never knew that it would have an impact on the walls too. Then I met the basement finishing guys online and they have been a big help. Their rates too are very reasonable. The situation is now under control and I am not worried about the rains anymore.

Angela H

Subject: Basement waterproofing

Our basement wall is concrete blocks and water comes in on one side of the house when rain, unfortunately is the side where our bathroom is. We want to ask the constructor and get an estimate on the price but what should we know before we hire one? What is the best solution to fix our water problem in the basement? Thanks


Subject: sump pump

I always bring my weeping tile into a sump pump then the pump shoots the water out into a drainage pipe in the backyard or drainage bed I always leave clean outs at the window wells for later maintenance with high pressure water jetting and clean out for my drainage pipe I recommend the home owner to calls us every 4 years for a 3 hour time limit to clean the weeping tile and drainage pipes and test the pump to make sure the pump is working at its best


Subject: Cement block foundation

Our cellar is not really wet, but being a block foundation it is musty in the spring and when we get lots of rain. What is the best solution to use on the walls to help contain this? Also my husband has COPD and we are trying to do everything we can to help keep the air cleaner.


Subject: outside waterproofing

I read your blog about waterproofing a basement and 95% of what you said is true. The outside waterproofing of only $80 to $100 a linear foot is not realistic. When excavating around a foundation OSHA requires for every 1 foot down, you have to dig 2 feet out for safety concerns. The only way around this is to supply suring around the excavation. This will add cost and time to project. A good rule of thumb is more like $130 to $140 per linear foot and this does not include what was ruined, steps, patio, hvac being moved temporarily, etc. The positive side waterproofing is a great option if you have deep pockets. The other downside to outside waterproofing is how to get rid of the water. If your grade of your yard is flat, then you have to bring this water into a sump and then pump the water away. Water only flows down hill, so if you cannot pitch the water from the footer to daylight, your only option is to bring the water in to the crock and pump it away.

Lastly, I have seen these outside systems fail after 10 to 15 years due to clogging of the exterior footing drain. Very hard to fix this problem unless you excavate again.

Waterproofer John

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Mold in a basement is a common problem. My company helps people with this every day. Some of the answers you received were helpful but not all the information is correct. First, you need to eliminate the two main ingrediants that mold needs to survive. The first one is water intrusion. This is a must. I am assuming you have no water intrusion as you make no mention. The second componant that needs to be eliminated is moisture. Moisture is also humidity. Basements need to be kept airtight in the summer months. Some folks have posted that you need air flow in your basement. Nothing could be furthur from the truth. When you open any windows for example, not one micron of air goes out of the basement, Warm humid air is sucked into the basement. Houses suck air into the basement and it meets the cool surfaces and skyrockets humidity. The windows must be kept closed and a dehumidification device installed to ensure humidity stays below 60% humidity. The dehumidifier should be energy star rated and purchasing a seperate humidity guage is a must to monitor the unit's progress. We like to keep our customer's basements at 50% humidity. This eliminates the smell that is active mold spore growth. Once the water and humidity is brought under control. Remove the organic materials that have mold on them. Walls, sheetrock and studs that have been affected. Follow the advice of previous posts as you must ensure that you do not affect the rest of the home. Once removed, install new walls using as much inorganic material as possible. We also install vapor barrier over the walls and seal the floors to stopwater vapor transmission into the basement. Poly plastic is not a acceptable vapor barrier. It is not "zero-perm" and will still allow moisture transmission. It will also crack and break into pieces over the years. A PVC liner rated "zero-perm" is the correct product in this application. Depending how large the basement is and if it is sectioned off will determine the dehumidifier strength. We use the Santa Fe line of dehidifiers as they are super energy efficiant and work like a dehumidifier on steriods. I hope this helps and I wish you the best in Basement Health!

Where is the home located, what is the exterior wall construction and type, how is the space heated?


It could be a whole host of different scenarios that would generate that result.  It is nearly impossible to tell but I would say that most basement moisture problems are a result of bulk moisture intrusion or condensation issues. 


Given the deep and hard winter this year, it could be a condensation issue that hadn't previously been shown.