Ask The Experts
Foundation, Drainage and Water Control
The concrete foundation of our newly built home is cracked in several locations. Our builder says that this is normal and won't cause any problem. I'm not convinced. How can I fix the problem?
A certain degree of cracking is normal in concrete or block foundation walls. The masonry shrinks as it cures, often resulting in visible cracks. If these cracks are ¼ inch or less in width , and show no evidence of corresponding settlement, as observed at the top of the foundation wall, or offset, as viewed from one side of the crack to the other, then it is likely that the cracks are related to shrinkage rather than any significant movement of the foundation. Even if slight evidence of movement is observed with any of these cracks, initial minor movement is common as the house foundation and adjacent soils settle into position following the construction process. This is not necessarily serious, nonetheless, monitoring is always wise. Low quality concrete, poorly designed footers, inadequate soil compaction, and poor drainage are all conditions that could result in serious structural problems. Record your present observations and date them, so that you can follow-up with new measurements over the next year or two, and determine if any movement is ongoing. If you suspect that movement is ongoing, based on your observations, you may wish to call in a professional for further evaluation, such as a professional engineer specializing in soils and foundations.
My home was built in 1949 and has weep holes in each corner of basement. Would it be advisable to plug and with what? I get water coming in at spring time once a year for about 3 or 4 days. Please advise, thank you.
The question we need to answer first is whether water on the basement floor drains to below the slab through the weep holes or water from below the floor rises up through the weep holes. This should be monitored. If the water comes up, seal the holes, if the water drains out, leave them open. Seal the holes with hydraulic cement. More importantly, why is there water in your basement in the first place? While it doesn't happen too often in your house, there are usually ways to reduce or prevent the water entry that can be accomplished from the exterior, including cleaning or replacing roof gutters, extending gutter downspouts away from the house, replacing or abandoning bad drain tile, and adding soil or re-grading to ensure that the ground slopes away from the house. Put on a raincoat and hike around the house in the rain to see what's really going on.
I have two vertical cracks in my concrete foundation walls, that are about1/4 inch wide at the top, and taper to almost no gap at the bottom. Should I do something about these cracks?
Foundation cracks should always, at minimum, be monitored for evidence that movement might be ongoing. It is hard to gauge subtle movement in cracks unless the cracks are patched first. So grout the cracks with cement and then keep an eye on them. Vertical cracks in concrete are often due to shrinkage of the concrete as it cures, and are not necessarily indicative of any settling or lateral movement at all. If there is no visible evidence of previous movement in the walls, such as a significant offset in the concrete from one side of the crack to the other, or visible inward bowing, or visible dropping of the concrete on one side of the crack to the other, or corresponding cracks in the living space finishes above the cracks, it very unlikely that the cracks are structurally significant.
On the other hand, if any of these signs of significant movement are associated with the cracks, it is wise to have them professionally inspected. It is also a good idea to make sure that ground water around the house, and especially in the areas of the cracks is being properly controlled. Freeze pressure from excess water in the soil close to foundation walls is the leading cause of ongoing foundation cracking and movement. Make sure the ground around the house is sloping well away, and that the gutters and downspouts are directing water well away from the foundation.
I have a two car detached garage built in the 1950s. It has a concrete floor and block foundation walls. In the last few years the foundation has started shifting heavily, cracking and moving outward, leaving a gap at the concrete slab. What is going on and how do I stop it?
The foundations on garages are often not very deep. In fact many garage foundations consist of a concrete slab poured on the ground with only a thickened portion around the perimeter, constituting both the garage floor and foundation in one pour. This is called a slab-on-grade foundation. This can be successful if properly installed and maintained. But, in our climate frost can drive fairly deeply into the ground in winter. When water freezes in the ground it expands approximately ten percent, moving the soil and anything that rests on it upward, including your foundation. In your case, you have a separate foundation from the concrete floor, but it probably doesn't go very deep in the soil, maybe only a foot or two. This can allow the moisture in the soil to lift the foundation repeatedly as the ground freezes and thaws. As the foundation moves up and down it creates a rocking effect that over time tilts your foundation outward, since the floor inside prevents any inward movement, and the outer edge of the foundation bearing surface is most affected. This is a common problem with shallow depth foundation walls.
The best approach to prevention is good drainage. If the soil is dry, very little freezing and lifting can occur. Gutters should be installed with well extended downspouts and leaf guards, and should be well maintained. The ground, preferably consisting of high clay content topsoil, should be sloped well away from the garage to direct surface water away from the foundation. Adding soil around the garage will increase the effective depth of your garage foundation, reducing the likelihood of lifting due to frozen soil. If the movement is not yet too severe, this may solve the problem. If the movement has resulted in damage to the framing, or inadequate support of the framing, replacement of the foundation is likely to be necessary. Ideally, the bottom of the new foundation footer should rest on soil that is 42 inches below the ground surface.
I have a 1930's house with a concrete foundation. The surface of the concrete is very weak and crumbly. How serious is this, and what do you recommend to stop the damage?
The deterioration that you are seeing is called spalling. The surface of the concrete is crumbling because the quality of the concrete is poor. The concrete produced in the era that your house was built often contained unwashed aggregate, which weakens the bond. Spalling can be a minor irritation or a major issue, depending on the extent and rate of deterioration. If the spalling is less than an inch deep, there is probably nothing to worry about. The best thing you can do for your foundation is to keep it as dry as possible. Moisture and freezing accelerate the damage. This is why the worst deterioration is often around basement windows. Keep the grade around the house sloping away and maintain your gutters and downspouts. It may be advantageous to apply a cement plaster to the affected surfaces since this will reduce moisture penetration, and will obviously improve the cosmetics.
If the spalling is deep and extensive, and the remaining surfaces are very loose, the foundation may not provide adequate support for the house as the crumbling continues. In some instances deterioration below the sill plate results in unsupported wall framing above, or the weakness results in inadequate resistance to lateral pressure, causing cracks and inward bowing of the foundation walls. If the concrete comes off the walls by the fistful, it's time for a new foundation. This is not necessarily as drastic as it may sound. The foundation can be replaced in sections, using temporary support for the framing as you go. Normally foundations are replaced using concrete block, which can usually be laid right on the original footers. Access problems caused by porches, additions, trees, or tight lot boundaries can be the biggest difficulty when replacing a foundation, but most of the work can be done from the interior, if necessary.
I have an older mobile home on my own lot. I have read somewhere that mobile homes should be tied down. During recent high winds it felt like my house was moving. How can I tell if it has been properly secured?
Chances are good that your mobile home isn't secured at all. Historically, tie-downs have only been required in coastal areas per HUD Code or in states with high tornado risks, based on state or local regulations. This is changing, with most lending institutions requiring proper tie-downs of all single and double wide mobile homes. In any case, it's a very good idea to secure your home. Mobile homes are relatively light weight in relation to their size, making them particularly vulnerable to high winds. And while tornadoes don't really seek out mobile home courts, when high winds do hit mobile homes they do far more damage and cause far more injury than when the same winds hit conventional stick-built or modular homes.
A mobile home is built on a steel chassis that is designed to take it down the road. The chassis remains in place as part of the support structure of the dwelling and typically sits on top of a series of concrete block piers which rest in the soil or on a concrete pad. You, or someone you trust, should open up the skirting at a few locations around the unit and take a close look at the chassis to check for heavy duty metal straps or cables that loop around the frame and tie to anchors in the soil or concrete slab. They should be easy to find. There should be at least four on each side, (ideally one every 6-8 feet), and they should be tight. They should be installed at a diagonal down from the frame to the ground toward the outside edge of the unit on each side. If you don't see them, call in a local mobile home installer to put them in for you.
Loose tie-downs may be an indication of settling or shifting block piers, which should be further investigated. While you have someone looking below your home, check for cracked block piers, tipped piers, or loose or missing shims between the piers and the steel beams. These are likely indications of poor drainage and settlement. Good drainage is at least as important around a mobile home as it is around a home with a full basement, to ensure against frost heave and shifting foundation piers.
We have a debate going in our house regarding gutters. Basically it comes down to whether they are worth the trouble.
You are not the only ones with mixed feelings about keeping gutters on the eaves of your house. They tend to clog up, ice up, fall-off, or just look unappealing. The percentage of homes sporting eavestroughs varies widely in our part of the world. In some areas less than 50% of the homes have roof gutters.
From a home inspector's point of view though, they are absolutely, positively, vital to the life of any house in a wet climate. Properly maintained gutters prevent excess water from the roof from concentrating close to the foundation of the house. Excess water against the foundation often results in water entry into the basement, which of course is undesirable. But even if no water entry is occurring, the water washing down through the soil may be slowly clogging your footer drains, the drainage system at the bottom of your foundation that carries water in the ground away from the house. If this system becomes clogged, chronic water entry into the basement may become inevitable. In addition, excess water may wash out bearing soils beneath the foundation, causing cracking and settling, or the water in the adjacent soil will freeze in winter, causing pressure against the foundation that can result in inward bowing and possible failure.
Perhaps even more important than danger to the foundation is damage to exterior finishes. When water drips off the roof, it splashes onto the finishes below. This is especially true where an uncovered entry stoop or the ground is close to the siding. Where splash from the lack of gutters occurs, decay is almost inevitable.
Regarding the downside of gutters, there are a few solutions available. Good quality metal gutter screens, or other debris shedding methods, are available to prevent clogging. Electric heat tape in the gutters can help prevent icing up, and ice-and-water shield applied along the eaves can prevent water from backing up through the shingles behind any ice. Most gutters fall off because they simply do not have enough fasteners or the hangers are the wrong design for the type of eaves. Gutters may be a nuisance, but they are a cost effective system that helps protect the house against serious damage. Do your house a favor and help it fend off the ravages of water with a good gutter system.
I am having my house built on a fairly steep lot and am worried about water problems in the basement which will be finished. What steps should we take to make sure it will be dry?
It is always better to prevent the water from getting to the house, than to attempt to control it after it gets there. Ground water is going to arrive in two different ways from two different sources; from underground flows and from rain or surface water seeping into the ground in the immediate vicinity of the house. Water flowing underground should be addressed by installing a good perimeter drainage system down at the foundation footer level. The trench around the house should be filled with drain tile and crushed stone from a level even with the bottom of the footer to a level well above the top of the basement floor. The gravel in the trenches should be protected from potential clogging from the soil above by installing landscape fabric before backfilling with soil. The drain tile should be directed to one or more downhill locations to outflow at the surface of the ground. The outlets should be well marked and protected from any blockage from vegetation or debris, and from any damage, such as from vehicles. Whether drainage from underneath the basement floor should be tied into the perimeter drain will have to be determined by conditions found after excavating for the foundation.
Surface water should be controlled by installing good gutters and extending the downspouts well away, as well as by sloping the ground away from the house on all sides to at least six feet from the structure, ensuring that water coming down the slope will be directed around, rather than toward the house. The soil near the house should be dense topsoil with clay content to reduce water seepage into the ground close to the foundation. The only other critical consideration is the foundation coating. There are several products on the market that will provide a continuous water resistant membrane, with or without a drainage plane, applied directly to the exterior of the foundation wall from the surface of the ground down to the footer, ensuring that water will not wick through the foundation or find a path through the inevitable foundation cracks.
I have been told that I should add soil close to the house so that water won't come into my basement, but then my basement windows will be covered with dirt. Should I eliminate the windows?
Removing wood or steel framed basement windows and filling the opening with well sealed concrete blocks, with a good water resistant coating applied on the exterior, is one effective way to allow for additional soil against the foundation. Removing the windows has the advantage of increasing your security against unauthorized entry, eliminating a very common location for water entry, and eliminating a very common source of termite infestation. Wood framed windows close to the soil are an open invitation to ground dwelling termites to work their way into the house.
Getting rid of your windows, however, is not the only way to solve the problem, and has the disadvantage of eliminating a source of light and fresh air in the basement. Eliminating your windows is not even an option, if they are part of a necessary means of direct escape from living space in a basement, or a part of required light and ventilation for living space. For unfinished basements with standard basement windows, common galvanized sheet metal bow shaped window wells are an easy solution. They come in varying dimensions and should be sized to reach 6 inches below the bottom of your window and to rise a couple of inches above the intended finished level of the ground surface. Soil should be excavated within the window well to 6 inches below the bottom of the window, and added around the outside of the well to make sure that any water on the surface of the ground is going to be directed away. Adding some crushed stone or brick chips in the bottom of the well is a good way to help ensure drainage, and, if excess roof water due to missing or clogged gutters may drop into the well, we suggest installing one of the readily available clear plastic arched covers to deflect the water from the roof.
I have a crawlspace under part of my house. In the fall I replaced the old insulation with new, (paper side exposed), laid new plastic on the soil and cut three openings for ventilation. Now I'm finding condensation dripping from the insulation and puddles on the plastic. What do I do to stop it?
Unfortunately you have set up a classic scenario for condensation problems. While the plastic on the ground was a very good idea, installing three vents was not. Warm air holds more moisture than cold. When warm summer air at 90 percent plus humidity enters through the vents, it cools and condenses on contact with the paper on the insulation, and the plastic on the ground, because they are cooler surfaces. If you drop the temperature of super humid air, condensation is bound to occur. In theory, more vents could solve the problem by increasing air flow and warming the entire crawlspace. However the amount of ventilation necessary would be so extreme that your crawlspace would be almost completely open to the exterior, allowing likely critter entry and cold problems in the winter. You are far better off ensuring that the plastic on the ground is well sealed and eliminating the vents.
You have installed the insulation upside down. As a rule of thumb, if you can see the paper on installed insulation it is wrong. It is not contributing to your problem now, but it will in the winter, when moisture from the heated living space migrates through the floor and hits the cold paper. Reverse the insulation and use “push wires” to hold it up.
My new house was completed in the late spring. The basement has been wet since we moved in, and now I'm getting water on the inside of my windows. The builder says that this will go away. I'm worried about mold. What can we do to stop it?
It is possible that the perimeter drainage system around the house is not adequate, that the gutters are not installed, or installed properly, or that the immediate ground around the house is not sloping away adequately, allowing water to enter the basement. This excess water would then evaporate and move throughout the house. It is also possible that the clothes dryer is not venting properly, a humidifier on the furnace is set too high, or other issues involving your lifestyle are producing too much moisture. However, the far more likely scenario is that the moisture is due to the normal drying process of the materials used to build your house. Massive amounts of water are released from the wood framing, concrete, and plaster as these materials dry during the first year after construction. Moisture in the air condenses on cold surfaces, so it is natural that the concrete walls and windows would become wet. Even the best windows are relatively cold compared to the insulated walls in your home, resulting in condensation when there is too much moisture in the air.
You are right to be concerned about mold growth. Chronic moisture is the key added ingredient necessary for mold growth in the house. The excess moisture may also cause staining or other damage to the finishes in the house. Your best approach will be to temporarily dehumidify the space with a couple of standard residential dehumidifiers. One in the basement and one in the living space should be sufficient to keep the moisture levels in check. The dehumidifiers should reduce the moisture sufficiently if set at a rough middle point between the highest and lowest settings, or "normal", or if the unit has a relative humidity reading, 40% or less. Dehumidifiers require relatively warm temperatures to work properly, so you may have to keep the basement 65 degrees or higher. If the units run for extended periods of time and either ice-up or don't fill with water, they are not working properly. In our climate it may be wise to run a dehumidifier in the basement every summer, in any case.
I have white fuzzy stuff growing in several areas on my foundation walls in the basement. Is this mold, and how do I get rid of it?
While white molds are common, we are unaware of any white molds that grow on masonry. What you are seeing is almost undoubtedly efflorescence, not mold. Efflorescence is actually mineral deposits left behind as moisture that has moved through the foundation walls evaporates from the interior surface of the masonry. Since the minerals can't evaporate, they remain and can build up to form fuzzy looking collections of small crystals. They are harmless, and can be easily washed off with a sponge or brush, and water. But, expect them to return over time unless the moisture conditions are corrected. The moisture is passing through the walls because the masonry is porous, or small cracks are allowing the seepage to occur. The moisture that is entering the house through the foundation walls can result in mold growth and damage to other materials in the basement, or even the rest of the house. So control is recommended.
The first step is to make sure that your gutters and downspouts are working well, and that the ground is sloping well away from the house. Your foundation should have a water resistant coating on the outside from the surface of the ground to the bottom of the walls. This may have been omitted, or poorly applied. Since a proper application would require complete excavation around the house, we suggest applying a masonry sealer on the interior surfaces as an alternative. The best type of interior sealer is a cementious type of coating, such as Thoroseal, which comes in a powder form to be mixed with water for application with a barn brush. If the foundation walls have already been painted, then a paint based sealer may be your best option. Any loose material should be brushed off the walls before applying any sealer. If you are seeing any significant amount of efflorescence, you should probably also install a dehumidifier in the basement to control moisture in the air. To avoid dumping the bucket every day, a means of automatic drainage is recommended. A trap should be employed if the dehumidifier is set up to drain directly into plumbing waste pipes. While efflorescence is harmless, the moisture that leaves the white fuzzy stuff behind is definitely not harmless, and should be controlled.
Last spring I started getting a lot of water on the rear wall in my basement. It pretty much went away by mid summer, but some of my stuff got ruined. It doesn't seem to leak during the fall or winter. What would be best to stop this seepage?
Based on the information in your question, we suspect that the moisture isn't due to leakage at all, but rather due to condensation. Under the right conditions, so much condensation will occur that the buildup can result in puddles and slowly flowing water on the floor. Condensation occurs because cold air can't hold as much humidity as warm air. Consequently the moisture in the air condenses on cold surfaces. In the springtime we can have ideal conditions for this to occur. The ground remains cold in the spring, while the air warms quickly and becomes humid. If warm humid air enters the basement, the moisture will condense on the cold foundation walls. The condensation will be worst on the surfaces that are the coldest, which will typically be the north facing walls. The worst thing to do on a warm humid day is to open the basement windows and allow the humid air to enter the basement. If you're worried about moisture in the basement, the best thing to do is to keep the windows closed and install an automatic dehumidifier, set up to flow to a sink or floor drain so you won't have to remember to empty the bucket.
If you are unsure whether the moisture you're seeing is from leakage or condensation, you can try a simple test. Dry a section of the wall and tape a large piece of aluminum foil tight to the surface. If moisture appears on the face of the foil, you'll know that condensation is the culprit. If the foil surface is dry, but the wall behind is wet, then it may be that moisture is seeping through the wall. In either case though, you'll want to control excess water around the exterior of the house and dehumidify the interior.
I never used to have water in my basement, and now I've had water three times when we've had heavy rain. What has changed and what can I do to stop it?
No basement is guaranteed to be immune to water entry if the weather is bad enough, and we have certainly experienced some weather extremes in the last couple of years. We have seen some instances locally where underground water patterns have been apparently changed, just as streams and rivers have been changed, by the extreme conditions we have recently experienced. This has resulted in chronic water entry where none occurred before. However, in most cases water entry during extreme weather is the result of readily correctable conditions above ground around the house. Your first line of defense against water entry is the slope of the ground at the foundation walls. The ground should be sloping away from the house on all sides to a distance of at least six feet. Your house should in essence have a shallow dam of dense soil against the foundation walls. We repeatedly see people attempt to control water by installing crushed stone against the foundation to provide drainage. The problem is that this drainage only directs the water toward the foundation, not away. If the surface of the ground is hidden by crushed stone or mulch, the poor pitch toward the house may be hidden. The gravel or mulch will have to be temporarily removed to improve the grade.
The second line of defense is your eaves troughs. Gutters should be properly sized and properly pitched to provide adequate water flow. Larger gutters or more downspouts may improve water control. Make sure the gutter downspouts are well secured and have adequate tailpieces to ensure that water is directed well away from the house. Finally, the most likely cause for increased basement water entry may be loose and sagging gutters, or clogged gutters, resulting in concentrated excess water against the house. Take a walk around your house in the next heavy rain, and see what happens to the water. You'll probably be able to make the diagnosis yourself.
I have had water problems in a crawlspace below an addition on my house. I re-graded the exterior and fixed the gutters, and I have added a plastic vapor barrier on the ground, but I still have excess dampness and there are puddles on top of the plastic. What else can I do?
I would suggest walking around the exterior during a hard rain to look for any weaknesses in your exterior water control system. Be suspicious of any drains that might be damaged and misdirecting water, check around window wells for water buildup, and make sure that any mulch or gravel is not hiding ground that might be sloping toward the house. Assuming that there is nothing more to be done on the exterior, the next steps may involve some additional work in the crawlspace. You may need to install a sump pump with a sealed cover in the crawlspace. You should use a heavy duty plastic sump pit designed for the purpose and a submersible pump with the switch mounted on a vertical float rod. Water from the pump should be piped to the exterior, and the pipe should be properly pitched to prevent freeze problems in winter. In order for the sump pump to work properly you may need to re-level or channel the ground below the plastic sheeting in the crawlspace to direct the water to your sump location. The integrity of your plastic vapor barrier may also need to be assessed. It should be well lapped and well sealed. Depending on the water source, it may be wise to run the plastic up the foundation walls to an attachment point at the top of the walls. If the foundation is made of concrete blocks, look for any open cores on the top of the blocks. These should all be sealed with foam insulation board, spray foam, or plastic sheeting to prevent moisture from exiting from the block cores into the crawlspace air. Make sure any vents to the exterior are fully closed and sealed, and if possible, open the crawlspace to the adjacent full basement to allow some air exchange. Another step that might be helpful would be to install a room dehumidifier in the crawlspace, piped to drain to your sump pit or other appropriate location. These units are expensive to operate however, so you may want to consider blowing a small quantity of air from the living space into the crawlspace instead. This air will be warm and dry for a presumably lower cost and will help reduce the moisture in the crawlspace. If the air from the living space is humid from summer heat, the cool crawlspace will cause moisture to condense out of the air, making things worse, so this idea will only work in summer if you air condition your living space.
I am interested in buying a forty year old ranch type house with a concrete foundation, but it has a couple of visible vertical cracks in the foundation. Is there any way I can know if this is a serious problem or not?
Most concrete foundation walls have one or more cracks. Masonry shrinks as it cures, often resulting in visible cracks. In most circumstances this is considered normal and acceptable. If the cracks are ¼ inch or less in width, and show no evidence of corresponding settlement or other movement, it is likely that the cracks are related to shrinkage and are not a cause for concern. However, if the cracked wall is visibly bowed inward, or is higher on one side of the crack than the other, or if the wall has shifted inward on one side of the crack compared to the other, then actual foundation movement has occurred and, depending on the degree of movement, further evaluation may be appropriate. Slight movement observed at foundation cracks is common as the house foundation and adjacent soils settle into position following the initial construction process. This is not necessarily serious, but monitoring is always wise.
Low quality concrete, poorly designed footers, inadequate soil compaction, and poor drainage are all conditions that could result in serious structural problems. Any evidence of significant foundation movement should be professionally evaluated before purchasing the home. If you are concerned with cracks in a home that you already own, you may wish to measure, record and date the degree of cracking or movement so that you can follow-up with new measurements over the next year or two, and determine if any of the movement is ongoing. In addition, improving the drainage around a home will help ensure that minor movement does not become a major structural concern.
One block foundation wall in my basement has a long horizontal crack about a third of the way down the wall, and is bowing inward about an inch, and I think it's getting worse. I added some support posts to reduce the load on the wall. Can I just reinforce this wall or do I have to replace it?
You have numerous repair options available to you. We can review the most common, but first we ought to deal with the causes for the movement. Usually block foundation walls push inward due to pressure from the ground on the exterior as it expands due to freezing. The wetter the ground, the more ice will form in the soil and the more pressure there will be against the wall. Improving exterior water control with proper grading and gutter maintenance may significantly reduce or prevent further movement. Also, while it may not seem logical, your foundation wall was more stable with the weight of the house still resting on it. Think about how much easier it is to knock over a stack of children's blocks with no weight on top than when you're pushing downward on the stack. If your wall has only bowed inward one inch, you should probably put the load back on the wall.
Cracks and bowing foundation walls are always “red flags” to buyers, but replacement of the affected foundation in this case really shouldn't be necessary. The easiest form of reinforcement is to install masonry pilasters or steel girders mounted vertically against the wall. They would be firmly anchored to the concrete basement floor and to the wood floor framing above. The appropriate spacing between the pilasters, the size of the pilasters, and the best anchoring methods would depend on the overall condition of the block wall, the height of the wall as well as the exterior grade, and the type and configuration of your floor framing. While common sense can be a good guide, these are determinations best made by a structural engineer. Once the reinforcement has been installed it would be wise to seal the horizontal crack with masonry cement or grout to help in monitoring for any further movement.
I have a fifty year old home with a finished rec. room in the basement, including a wood floor. The wood floor is starting to get soft in some areas. What can I do to prevent this?
As you have probably surmised, the softness in the floor is most likely due to chronic moisture and resultant decay, although termites might also be the culprit. This is not a good situation. In fact, moisture susceptible finishes in a basement are almost always a bad idea to begin with. Even in a well sealed basement with good exterior drainage and proper landscaping around the house, major weather events or accidents are still likely to result in incidences of moisture buildup and damage to basement finishes. Wet interior finishes will result in decay if the moisture is chronic, and at the very least, staining and mold growth if the water entry is only periodic.
At a minimum the wood floor in your basement should be removed. We also recommend that the finishes be removed along the base of the walls, and the walls inspected for decay. Any moldy or decayed components that are discovered in the walls should be removed. In our opinion it would be best to remove all carpeting, gypsum board, and wood finish materials from the basement if repeated moisture damage is occurring.
It isn't necessary to finish the basement in moisture sensitive materials to have usable living space. Simply painting the concrete floor and foundation walls, if in good condition, may result in a pleasant environment without major risk. For higher quality and more comfortable finishes, vinyl composition tiles or ceramic tiles applied directly to the concrete make a mold resistant and durable floor covering. And, using pressure treated lumber for wall framing, closed cell foam insulation, rather than fiberglass, and cement board or other moisture resistant wall finishes near the floor, will provide walls that are good looking, energy efficient and durable.Don't forget to check on your gutters and exterior drainage to try to reduce the amount of water close to the house that might seep into the basement. It may also be necessary to install a basement de-watering system. The most common type consists of crushed stone and drain tile installed below the basement floor adjacent to the foundation walls. The water would be directed to an appropriate exterior discharge point or to a sump pump.
We have had a slimy brown substance coming out of the wall of our basement. About 6 years ago they redid the street behind our house, and this is when the problem began. What should we do about it?
While the brown water is undoubtedly objectionable, it is essentially harmless. The slime is almost certainly iron bacteria. Iron occurs naturally in the soil in varying concentrations, and is often found in well water. When the concentration of iron is high enough, iron bacteria live off the ferrous oxide, and produce the slimy brown mess that you see. When the street was redone, they may have changed the direction of water flow, resulting in the seepage into your basement. The best thing that you can do is to seal up the hole. It may be possible to do this from the interior with hydraulic cement. But to be fully effective you may have to excavate on the exterior to the point of entry and seal the outside of the foundation.