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stop roof leaks, roof repair

Painting over Water Stains and Mold: How to Repair and Prep After a Water Leak

What is the rule of thumb for painting over water stains? I have a two-story house, and my second-floor shower stall developed a leak, as evidenced by water dripping from the first floor ceiling. The leak is small--a few drops of water after every use--and I believe I have now fixed the source of the leak (failing, cracked grout).

Now that I'm preparing to repair the ceiling, I see that the water dripped out around a nail head which developed a quarter-sized black stain that I assume is black mold. A few inches away, the paint has cracked and is peeling along a two-foot-long drywall seam. I was hoping to simply remove the loose paint, clean the black area with some bleach, re-spackle and re-paint the existing drywall.  Will this work or do you think that I should remove and replace the affected drywall to eliminate the black mold in the ceiling?

Our Answer

Before we get to painting over water stains, let's talk about mold. Mold needs three things to fester: air, food and water. While there is plenty of air and drywall is a terrific food for black mold, the fact that you have fixed the leak means that there should be no more moisture to feed a mold problem.
Secondly, the black mold that you think you have, may not in fact be black mold at all. While mold is possible, water stains--caused by the reaction of water with paper, paint and rust--can also form a black spot. Regardless, a quarter-sized area is nothing to worry about, even it is black mold, as long as the leak has been repaired.

As for painting over the water stain, my suggestion is to most certainly remove the loose paint as you suggested. Then wash the area down with a bleach-and-water solution just to make sure any mold spores have been neutralized. The next step is the most important: paint the stained area with an oil-based primer like KILZ. This will seal the stained surface and prevent it from leaching through to the top layer after you paint. For the best results, prime the entire area and not just the spots that have been impacted by the leak and resulting water stains.

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Water Damage on Flooring

Water Damage in Flooring

We recently discovered our refrigerator water line had been leaking for some time. We have gotten the leak fixed and are now dealing with the damage. We discovered the leak after water began coming up from between the planks of bamboo flooring in the living room, which is on the other side of the wall that the fridge sits on. We have been in touch with our homeowners' insurance company and are working with restoration specialists they recommended. The large fans/dehumidifiers are drying things out, but we have learned there is water under the tile in our kitchen, too, and it may extend into the other tiled areas of the house.

My biggest concern is that we believe the previous owners laid the kitchen tile and the wood flooring on top of an original layer of tile. We have seen grout underneath the wood flooring when we replaced some trim a while back, and the seam between the tile and cabinets in the kitchen makes it clear that the cabinets do not sit on top of the top layer of tile. I am concerned that a lot of water may be trapped in the original layer of flooring and will not be dried up with the fans/dehumidifiers.

Our restoration specialist says the water can stay in the tile and it shouldn't cause damage other than grout discoloration over time. I'm not so sure. This seems like a big risk to me. Should we fight to have the top layer of flooring and the original tile both removed to ensure the water is all gone? I don't want to have problems later on or have mold start to grow.

Our Answer

You have a valid concern but my experience would dictate that there's little to worry about if the leak was fixed.  That water will dry out – and probably much quicker than you'd imagine.  The bigger concern is structural.  If the water leak went on for a long time, you may have rotted floor components and those should be fixed, even if it involves removing tile.

Try gently stepping on the floor in the are of the leak and note if it feels spongy or softer than adjoining areas.  If it is, further evaluation may be needed.  If a flooring replacement is needed, there have been many advances in waterproof flooring you can consider.

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Crawlspace Moisture Problem Solution: Vapor Barriers, Proper Drainage and Foundation Vent Fan Can Help

I have a major moisture problem with a home that is one block from Lake Michigan in South Haven, MI. I have a working sump pump below ground level and am still having rotting problems with the floor joists. A local contractor wants to staple plastic to the joists or lay it on the ground. Would you recommend either of these as a solution?

Our Answer

Moisture management typically involves several solutions working together. Adding plastic sheathing over the soil as a crawl space vapor barrier is a good start. Also check your outside drainage conditions. Gutters must be clean, free-flowing and discharging four to six feet from the foundation. Grading also has to slope away. (See our article on wet basement and crawl space tips.) If the crawlspace moisture problem is severe, another step might be to install a crawl space foundation vent fan, wired into a humidistat. The fan can be set to kick on whenever humidity gets high enough and pull drier outside air through the space to minimize condensation on the floor joists and the potential rot, mold and insect problems that could ensue.

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Mold in Basement Walls

Hello, I live in Canada and we had mold in the basement. We had the exterior of the house graded away from the house, and had a spray foam insulation company come by and spray foamed our basement walls. I have since finished the basement to use as a rental property.

Last year, due to the gutters not being properly attached, we had some water fill up a window well during a heavy rain fall and come in through the basement window to the finished basement. This occurred in August -- our tenants have stated that they smell mold in that room now (they didn't smell anything before).

Upon inspection, there is no mold on the finished drywall and I personally don't smell anything. I'm just wondering if it is possible that there could be mold behind the walls that they're smelling -- and if so, wouldn't the mold make it's way to the interior walls by now?

Any help would be appreciated. I know that the tenants never open the windows/blinds and kept the door closed for that specific room for awhile - so there was limited circulation.

Our Answer

John, the answer to your question is yes -- mold could be growing behind the drywall but I'm not hearing anything that tells me a major destructive investigation is warranted.  You could pull off some outlet covers, or registers or anywhere else you can get a peak behind but I would not recommend a major mold witch hunt.  First, a one-off leak like you've described doesn't usually cause a major mold problem.  Sure, it can happen but if you have a leak, fix it and then move on, you often dont have the sustained moisture necessary for a major mold infestation.  Also, I'm always suspicious when people say the "smell" mold.  Its not like mold has a distinctive odor.  They could just as likely be sensing the dampness since they dont ever ventilate the space. 

I will point out however, that drywall wasn't the best choice for basement walls.  There's a product called DensArmor which is a wall board with a fiberglass face, instead of paper.  Since the fiberglass is not organic, it can't grow mold.

Before you go any further, I'd suggest that you install a good quality dehumidifier in that area to really dry things out. Check out those from Santa Fe. Products.  I have one on my basement and it makes a bug difference, even though we also have all the exterior drainage set up correctly.  I'm attaching the video I did with them recently.  Hope this helps!

Tom Kraeutler

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mold in attic

Attic Moisture: Mold in Attic

I have moisture in my attic. I have rusted nails through my sheathing and it looks like mold is starting to form.

I have soffit and continuous ridge ventilation, and the bathroom and kitchen vents are vented to the outside. What can I do?

Our Answer

Moisture in the attic oftentimes can be frustrating.  More so when you have provided what is considered all the right things in ventilation and exhaust installs.

To understand why this is happening you must figure out what the moisture source is.  It has been my experience when issues such as yours has come up that the moisture source is coming from the inside living area of the home and is being drawn into the attic through was is called Stack Effect.

Stack Effect is the result of poor air sealing both in the basement and in the attic combined. Believe it or not, the basement has a lot to do with the performance of the attic vent system.   What happens is as the air in the house is warmed up it rises. Much like a chimney.  When this happens it moves up taking indoor moisture with it.  I am sure you or someone you know has a home that suffers from dry air in winter months?  This is all caused by air moving out of the home. When we think this air is moving out of the walls, and it is, most is going up and out through the roof.  The result is the moisture condenses on the colder areas of the attic. The nails and the area closest to the ceiling which is around the soffit locations.  As the air move up in the middle of the attic it tends to cool down and mix with the air in the attic and is drawn out through the vents.  But when it enters near the soffit it hits the cold roof before it mixes with the air in the attic and condenses.  This is why in most cases we find the attic stained near the soffit areas. But quite often then not we blame the soffit area for pulling in the damp air in that location.

In any case we need to stop the air flow entering into the attic. This will stop the moisture flow and the result will be no moisture, no mold, and no rusted black stains where the nails enter into the attic.

To do this we must first find were the air is entering. This is easy.  If the attic has insulation, pull it up wherever there is a wall below. This can be the outside wall area or where any wall that makes up a room below is located.  Look at the insulation. If its fiberglass you will see black stains in the fibers.  This is dust.  This dust is the result of air movement with the fiberglass acting like a filter. This is a sure fire method of finding exactly were the air is entering.  You will find it wherever wires enter into the attic, plumbing pipes, chimney come up and out. And even around the access hatch or staircase is placed. 

To fix this you need to purchase spray foam insulation.  I use the window and door type as it is a little less foamy then the regular stuff.  The standard foam in can expands way to much and can get a bit messy wen working with it.  In anycase, regardless of what foam you purchase, you need to pull up insulation and foam both sides of the exposed board that is the top plate of the wall below. Any wire openings you need to do the same thing. Plumbing as well.  When you get to the chimney you need to baffle this. Normally there is a fairly large space between the brick and the framing of the ceiling. This is done for fire protection. Purchase thin metal sheets and form and cut them to fit around the opening blocking off as much of the hole as you can.  Then using fire blocking foam.  Seal off the metal to the chimney and framing area.  Once done this would be a great time to add insulation while your up there.  But your not done yet.

Go to the basement and do the same thing. Purchase foam 2" boards and fit them into the mud sill area over the block foundation wall.  Using the high expansion foam (the messy kind) spray around the edges of the framing, place the precut foam boards into this space and foam them tight to the wood.  This will air seal the wall so no air moves up it towards the attic.  Foam all the pipe openings, wire openings and around the chimney in the same manner as you did in the attic.

Once done you not only will prevent this moisture from collecting in the attic on the underside of the roof, you will save a lot of heat and increase your comfort level by stopping drafts that pull the moisture out of the house.

In effect this is the same thing we do as Building Performance contractors  only using large foam machines instead of the little cans.

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Wet Concrete Floor

I am having a problem with the concrete floor in one of the rooms of the house we moved in to. Every time it rains the floor is wet. I don't know if there is any kind of sealant on it or not. The rest of the house has linoleum. But this room is just concrete. What can I do to fix this problem? Will the new flex seal work? or do I need to try something else?

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My Home Is Sick: Need Help


I found your website and I have been reading the articles. I have not found one that addresses my issue so I am writing to you. I am at my wits end with my house. I love the title of your of website because I have put a lot of money in my house and I still cannot sleep comfortable at night.

We are having symptoms that can be related to mold but we cannot find evidence of mold in the house.

Here is my background: I live in FL in a 1960 remolded brick house (1400sq) that is 100% tile and I have no pets. I do have ceiling fans and central air. I lived in the house for the last 3 years and for the last 2 we had several issues with mold that were fixed and remediated. Someone thought, maybe I did not get "all" the mold. Now, I still feel like "an eyelash" is in my eyes. This can be sitting up or lying down. My eight year old daughter complains her eyelashes hurt and her underarms itch. When she first walks into the house after being gone for several hours, she will sneeze at least 1x within 5-10min. It normally takes me longer to sneeze, but I will, let's say in the afternoon after being home all day. Since Oct 2015, I had several inspections to include thermal imaging and have no water leaks on the plumbing, roof, foundation or windows. All the areas that were previous affected were rechecked and nothing was identified by the camera or moisture meter. I have leather living room furniture and have taken out all the area rugs. I have central air and I have had the air ducts cleaned. I am changing my air filter 1x a month. In Oct, I also had my AC Tech open the inside of the AC unit and there is no condensation or mold visual on the coils or the blower. He installed a UV light. For the last 2 weeks that AC unit has been off because of the nice temperatures and I am still have the symptoms (AC on or off does not matter).

I had 2 Air Quality inspections. In Oct, the mold count for one room Main Living/Kitchen was a total of 11 (AC on) Ascospores (1) Aspergillus/Penicillium (6), Basidiospores (2), Curvularia (1), Smut/Myxomyces/Pericona (1). In Dec, I used a different Air Quality Inspection Company who used a different lab company. He checked three different rooms (AC Off). Main Living/Kitchen 17 -Ascospores (1), Basidiospores (12), Cladosporium (2), Ganoderma (2). My Daughter's bedroom-Basidiospores (9). Master Bedroom-Basidospores (6), Cladosporium (2) and Pencillium/Aspergillus (1). Both Inspectors are saying these numbers are so low that we should not be having these symptoms.

In Dec, I had my Carpenter to take down all old 1960 wood which included top kitchen cabinets, hall closets (framing, doors, baseboards) and 2 bedroom closets (framing, doors, baseboards). I used to say my daughter bedroom smelled like my grandma (this was her bedroom before she died). When we removed the baseboards in my daughter's bedroom closet the "funny" smell began stronger. But, there was no mold on the back of the baseboards. Then, I had 2 feet of plaster drywall cut at the bottom of the closet and there was no mold on the back of the drywall. Yet, the strong smell persisted. I then cut out the firm strips along the framing. The smell persisted. I have treated the wood framing with Fiberlock detergent and a brush. After that treatment I painted the exposed beams with a mold killing white primer. There is still a very faint odor when you walk in the closet. Is the smell connected to the allergy symptoms? Should I cut more dry wall and possible the wood framing?

I am confused because our symptoms can be felt in any room in the house. My daughter tested for allergies of dust, cats, dogs, oak trees. My test said I had no allergens. I have the special pillow cases and mattress pads. This has been a persistent issue. I am planning to have another air quality inspection to see what my numbers are all my latest efforts. I have wiped down every wall, floor, ceiling and baseboard with warm water and white vinegar. The house has new paint as of three years ago. I purchased the led paint test kit and rubbed it on all walls and it did not change colors.

Can this be from a gas? I have propane water heater, stove and oven. I changed my cooked top in Sep because with my old cooktop the pilot was lit all the time. When my new one was install (goes click, click then fires) the gas company came out to inspect and did a pressure test, everything was okay. I have a carbon monoxide monitor. We don't have the symptoms of the radon gas. The only other gas I heard of was plumbing gas. All my plumbing seems ok. The last inspector says I can get a more expensive test to see anything is "off-gassing." He also said there was some expensive solution that is used to clean sports locker rooms that can be sprayed in my house. As you may have guessed my anxiety is high over my house. Plus, my money is running low.


Our Answer

Hi Erica, I'm sorry to hear about the troubles with your house.  One question I have -- do your family's symptoms persist when you at NOT at home?  Have you take a few days away from the house and noticed the symptoms decrease?  If so, then the home may very well be the issue.

Its not possible to diagnose this from afar but I would be looking for a building scientist to help.  Diagnosing sick homes is very special skill and while some inspectors may find limited issues, its possible that they could miss the root of the problem.  

The other idea I might suggest you consider is an air ERV or HRV unit.  These are air to air heat exchangers that allow fresh air to enter the building to replace the stale air inside, but recover and heat or cool in the air so as to not drove up energy bills.  

Hope this is of some help. 

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USDA Rural Development Loan Failed to Identify Shoddy Contractor’s Work

Hi, I live in Athens, TN. My brother is a stroke victim. he had 3 strokes and double brain surgery. He cannot walk, or use his left arm. He is on SSD. About 1 year and a half ago, my disabled brother had a leak in his roof, that completely collapsed his bathroom ceiling. It was above the bathtub, and black mold was everywhere. He ended up getting in touch with the USDA, and took out a loan to fix the roof, and remodel that bathroom, making it a handicap friendly bathroom. The case worker for the USDA in Chattanooga told him to get 3 estimates. She gave him a list of contractors, and he called 2 of them, and she said the estimate was too high. The other contractors on the list wouldn't come out because we live to far from them. So, he got a referral from a man who does charity work for poor people. He knew a man who was the head honcho at the Mormon Church here, and this mans son worked on houses. we got the sons phone number. He came out and gave my brother an estimate, and his case manager approved it. The guy had his 2 young workers put the roof on, while he did the bathroom. He did electrical work and plumbing in the bath, and electrical in other areas of the house. When he was done, they set up and appt. for the case manager to come out and look over the work and approve it. If she approves it, and my brother approves it, than the contractor gets paid. They both approved it, but nobody went on the roof. I feel the case worker should have gone on the roof or had the City Bldg. Inspector come out and inspect it. She didn't. He got a 1 year warranty on the work, and the contractor was paid and on his way. There was 2 things he was supposed to come back and finish. A new faucet in the kitchen, and his workers left a gap in his wall between the molding around the front door and the wall. The cased worker took pictures. He never came back to finish it. My brother tried calling him many times, but his phone was disconnected. A year later, his roof starts leaking into the bathroom. the case worker says it is between the homeowner, my brother, and the contractor and washed her hands of the mess. I called everyone I could and found out that the contractor was supposed to be licensed to do any plumbing or electric, no matter how small the cost. In Tennessee you do not have to be licensed to put a roof on unless it is over 25K. We thought he was licensed, but the USDA knew he wasn't. My brother borrowed 14K to have this work done. Since we couldn't call this contractor, I went to his house, with tape recorder in hand. he said he would come out and fix everything. He took down our phone numbers and said he would call the next day. he didn't. A month went buy, the ceiling in the bathroom is sagging and has black mold on it, and we had to do something. I went to Angie's List and hired a top knotch licensed roofer to fix the leak. He was shocked at the shoddy roof job the last contractors workers had done. he said it is the worst he has seen in 40 years of roofing. he took pics of all the problems, gave us an estimate to fix the leak, and we hired him. He came to work 2 days ago, and while working on the roof, came across so many problems, that he could not believe the USDA signed off on it. My brother has mental problems and was just going by what his case worker said. I thought she was checking all this stuff out, but she wasn't. It cost $475.00 to fix the leak, but the roof needs to be replaced. In the meantime, my brother, who's SSD income is $790.00 a month, has to pay the USDA $45.00 a month for the loan. he pays for half, the USDA pays the other half. Now, the USDA got ripped off by this guy too, in my eyes. My concern is for my brother. How can he get part of the loan forgiven, so he can hire the new roofer to put a new roof on correctly and how can we get our $475.00 back from the con artist. Even though it was a 1 year warranty, the warranty SHOULD be for a roof that was installed properly. Since it wasn't, wouldn't that make the warranty null and void. What do we do???? Can the original roofer be arrested? Small claims court would be OK, if he shows up. I don't know what to do, and my brother is in tears. Please help me. Thankyou

Our Answer


Juliana, I'm so sorry to hear of your troubles with contractors.  Suffice to say, I have heard this all before.  I'm afraid that anything I told you to do right now would be too little too late. It does seem that the loan officer should bear some responsibility for missing the defects. At the bear minimum, they should have insisted that a building permit be taken out so that proper inspectors would have been made.

I think you are on the right track using a contractor from Angie's List.  Keep in mind that even though the roof may have not been properly installed, many times a roof can be repaired an maintained leak free without a complete replacement.

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Humidistat Fan or Dehumidifier for Damp Crawlspace?

I live in Nashville, where it's quite humid.  I moved into my first house last August and we have a stand-up crawlspace.  Around the exterior of the crawlspace, the builder put in four vents.  About a month after moving in, we started to see what looked like mildew and/or mold growing on the walls of the crawlspace.  I had a "mold guy"  come in and he recommended a dehumidifier.  I had a friend of mine who knows quite a bit about DIY stuff come to my house and he recommended getting a humidistat fan instead.  Before I rush out and buy one and put one in, what do I need to know about using humidistat fans?  Are there certain factors that make them uneffective that I need to be aware of?

Our Answer

Either approach - a dehumidifier or a humidistat fan - is a good approach. 
If you go with a humidistat, first make sure you have a vapor barrier across your entire crawlspace floor.  You also need to ensure that the vents on the opposite sides of the crawlspace open, so that once the fan kicks on, it pulls air from the crawlspace outward. 
If you opt for a dehumidifier, I personally just installed one from the Santa Fe Compact line and am very happy with it.  The version I selected is designed specifically for crawlspaces.  It's small - only 12 x 12 x 22 inches, yet hangs from the floor joists and takes out an impressive 70 pints of water each day.

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Get Rid of Mildew Odor in Furniture

How can the "old house" smell -- or possibly mold -- be removed from furniture? My father's furniture has been in mildew- and mold-scented homes, and now I want to move it into another home and not take the smell along. This particular old house had leaks and whatnot under the house in its past, but none recently. The house itself lost the scent when cleaned and painted, but because the scent remains in the crawl space, it's back. What can I use to get rid of it? Thank you.

Our Answer

It sounds like the odor that you're reporting is simply dampness. Moisture combines with dust and other irritants to give off an odor. The key here is going to be getting the furniture into a place dry enough for the moisture to evaporate - and the odor should go with it. Follow with a thorough cleaning of the furniture. You can often rent an upholstery-cleaning machine from your local home center and clean the upholstery yourself.

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Mold Growth Due to Air Conditioning System

If your System is over sized the air is colder. system runs a Quicker or cooling the air too fast not removing Humidity. Higher Humidity turns to Mold. The Air conditioner units cool the home and set the humidity level never turn off a vent in a room if your not in it. This make the Out Door heat and humidity enter the room. If you have return Air Vent in this room your pulling in hot air making system run longer.(I CAN BEVEIVE MONEY PIT SAID TURN OFF VENT IN ROOM'S YOU DO NOT USED)this IS INFO FROM 1970'S. And is not true. I keep my temp at 74-75 all the time if your not home the system runs shorter time due to no one opening doors. Now if a system is over charged this make evap., coil to cold too making mold in duct work. To Large system and under sized return in 99% of home's.

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Best Product to Clean and Prevent Indoor Mold

1. What types of health effects have been experienced by inhabitants of a home where high concentrations of mold exist?

2. If cleanup of mold is needed, can a combination of wiping with a bleach solution and then applying Microban be as effective as using a biocide, which may be toxic?

Our Answer

According to the CDC website, exposure to mold indoors has been linked to upper respiratory tract symptoms, cough and wheeze in otherwise healthy adults and children, and asthma symptoms in people with asthma. It has also been linked to hypersensitivity pneumonitis in individuals susceptible to that condition. For indoor mold cleanup, we would recommend a product called Concrobium. There are lots of benefits to Concrobium. It's safe for any surface, including fabric. It leaves a protective barrier when it dries. Bleach doesn't do that, and bleach is also not fabric-safe. Bleach will kill mold spores on application, but unlike Concrobium, it doesn't offer any ongoing protection.

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Roofing Mold/Mildew

I saw a product in my local hardware store called 'Wet and Forget', that claimed to remove the mold/stain on shingled roofs. Is this product effective in doing that? The stain has been on the roof for a few years. Can you suggest an effective way to remove the mold/mildew stains/ Thanks

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What’s the Best Way to Vent My Dryer Out of My House?

I had a hallway laundry closet built, but the contractor did not put in a vent for the dryer.  The closet is on the first level of my home, about halfway between the front and back of the house, and about 15 feet from the side exterior wall.  I can either vent the dryer through the floor and the basement ceiling, then out the back bric,k or I can go up and out of the attic.  Either way, I have to cut through flooring which I have never done.  This is all new to me but I am learning many things after being married 33 years and now on my own.  I can do it -  I just need to know which approach would be best.  Thanks!  Karen

Our Answer

First of all, congratulations on taking on these projects on your own.  There's a lot I'm sure you're capable of doing.  Keep in mind, though, that working beyond your skill set can end up being more expensive in the long run.  Opening up ceilings may be a little out of your league for you (and most homeowners, for that matter), considering you could hit wiring and make an electrical mess - or get hurt. 
In terms of the best way to redirect the dryer vent: As a rule of thumb, the shortest, straightest path out is best  If you vent up through attic, you'll notice it takes longer for clothes to dry because your dryer isn't strong enough to push air up efficiently.  And remember that every 90-degree bend in the ducting is the equivalent of 15-feet of straight ducting in terms of the energy needed to push air through - so any bend greatly reduces efficiency and potentially your dryer's performance.

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Toilet Ring, Sink Ring, Shower Shum?

I have listened to your show munerous times over the past years, Being an ex-contractorI find many subjects interesting,

One in paticlur. You are directing as  how to get rid of water rings and spots in toilets, showes, tubs, and toilets. You keep sending them to the store to buy chemicals which are detemental to the appliance and health of the use if not masked. Well here is a very simple way to get rid of hard water rinds, calicum, mangisum, and all hard water staining problems. From my house cleaner, which was like pulling teeth to get.

At Lowes and other hard ware stores, they sell a little product for sand sheet rock. Its balck and looks like sand paper. Looks and feels like it also.

Just wet the paper and sand off anywthin that stains applicanes. Workd great, even on glass shower doors, no scrratching of anything.

Good luck try it out first. Oh let me get to the store to stock up before this hit the airways.