claims they have a virtually zero permeance under concrete slab vapor barrier. • Vapor permeable: greater than 10 perms. Good luck. They put down a plastic Barrier which I discovered the other day had a puncture. Updated! Do I need to dismantle my rebar and styrofoam to dry the potential puddle sitting on top of the poly? The higher the number, the more permeable the material. We are laying a new basement floor for bedrooms and new lounge downstairs we are doing the footings 1st – would you recommend laying the plastic barrier in the footings trench also before we do the entire floor? I have a living room that used to be a garage. Thanks for the comment. After my recent rain damage, I pulled up the carpet and there was already mold and smaller mold spores forming. We purchased our home 4 years ago. I live in the St. Louis area, and it’s humid in the summer and can feel quite dry in the winter. I’m concerned that a vapor barrier would trap moisture underneath it. In May I noticed small droplets of water seeping out of the grout lines in several areas, by August 2016 there was grout discoloration in several areas as well as water seepage. I have been told to fold it upwards at the perimiter a couple inches, bringing it up in front of the baseboard, and then attaching quarter round against it. As long as there is moisture present in the concrete it will continue to get stronger and improve at an ever decreasing rate. the Spillmaster stuff was supposed to prevent mold from coming through yet it seem mold formed right at the seem of the foam and plastic/vapor barrier which is on the living space side of the upper ( the side i walk on) All answers are appreciated. My fear would be more about the floor being ruined than mold. What would be the best procedure to follow to remedy the issue. Hello, ASTM International gives specific guidelines in ASTM E1745-17 and ASTM E1643 for the use, installation, and inspection of vapor barriers used under concrete slabs. If any water vapor penetrates through a concrete subfloor, the vapor diffusion retarder slows the movement of the moisture, preventing damage to … we had a plumber come out and fix it by replacing the piping that had a hole in it. I’m just more concerned with prevention of mold growth and moisture. Good luck. We had thought about the vinyl laminate flooring but we are afraid it will mold underneath. Wow, what an experience. grade resins that can break down over time. Is it possible that a temperature difference between the slab and room above the wood is causing condensation to build up under the floor? What options do I have for vapor barriers/vapor mitigation? Of course, there’s also the moisture that was in the original concrete mixture. It helps reduce mold and condensation in buildings and is resistant to decay so it will protect against moisture emission for decades. We can’t afford to keep trying different things. A good place to start would be https://www.icri.org/page/ccsmtt_list look for a technician in your state. I have no way to answer that for sure. Moisture in concrete can occur from a variety of sources: ground moisture that contacts the slab through either capillary action or as water vapor, high air humidity or drastic changes in relative humidity in its environment, leaking plumbing that passes through the slab, and more. Great information. Hi Jason, The cooler was installed apparently without any vapor barrier between the slab and the outer wood of the floor structure. If so, what would I use? If Pergo is the finished product, I would start by calling their technical hotline (after quantifying the moisture levels) and asking them for recommendations or guidance. That reason is that it isn’t always indicating the moisture in the slab and if it does, you don’t know how much moisture there is in relation to a potential flooring failure. Nick. If your floor covering is bonded to concrete using adhesives with water, latex, and acrylic bases, excess moisture will emulsify and weaken the adhesive formula, causing many types of visible damage: Help me!???? Is it necessary or would you just make sure the slab is completely dry before going back with the felt, plywood and new hardwoods? should be enough. I’ve also had the roof and windows inspected. Moisture Barrier Under Concrete New buildings that are built on concrete slabs may already have a moisture barrier built in to the concrete slab. As far as installing the laminate, I would contact the manufacturer of whatever product you chose and have them give you some recommended solutions. my mother had a slab leak inMay and it flooded her whole house. This may help you understand better. Next, I am not an expert on modified or unmodified thin-sets, but I would think the thin-set manufacturers would have specifications regarding any (if any) vapor barrier characteristics. As far as barriers, especially if you are using one to compensate for the possibility that you don’t have one below the slab, you get what you pay for, in my opinion. We are in Florida and would like to know the best method for installing 6 mil poly vapor barrier over our concrete slab, prior to putting down laminate flooring. Thanks for the question. We had a new draining system installed, Drylock was painted on the outside slab and gravel was installed alongside the house wall. It’s a 15 year old house, but we’ve only been here 4 years, so I don’t know how long this has been an issue. Just my opinion. The cooler is sitting on a bare slab appx 6’x16′. Also, would you see a need for wire mesh in this situation? In various places around the house we installed a gypcrete leveling course (1/2″ – 5/8″) and then a glued down engineered wood. I have never heard of anyone utilizing poly to increase the strength of the concrete. I would also look to see if potentially doing one of the planking systems that allows for a floating installation may not bring something positive to the table. Thanks! Hi Jason, A concrete vapor barrier is any material that prevents moisture from entering a concrete slab. It may not be near the surface, but that doesn’t mean it’s not there. Thanks for the question. While I cannot soak up any excess moisture with a towel, a Damp-Rid container fills up in about 3-4 months time, so there is definitely excess moisture in this one room. Our garage floor gets damp and slippery when it’s humid out which is often in WI. © Copyright 2020   |   everything-about-concrete.com   |   All Rights Reserved. Unfortunately, the re-purposing of areas, whether commercial or residential, can lead to problems like this. This leads me to believe it’s condensation. I hope this helps. In one room on the first floor we wanted to remove the rather low drywall ceiling, metal studs and framework then apply nickel gap shadow box ship lap on the ceiling to create more headroom. Would drylock on the floor first prevent the moisture capillary affect or whatever it is that is happening? Block foundation, built 1952. basement window will corrected before flooring installation FYI lol. How high are the moisture levels? Thanks for the question. My uncle had the cooler installed appx 10 to 15 years ago. As moisture makes its way to the surface of a concrete slab, soluble alkalies come along for the ride and raise its surface pH above that of flooring adhesives. If I had to guess, I would say this has something to do with dewpoint and the surface temperature of the concrete. The house is on a concrete slab. What is your thoughts on this? This causes the adhesives to breakdown and you end up with flooring failures such as swelling, bulging, or cupping. You may also want to investigate products like these: https://www.schluter.com/schluter-us/en_US/Membranes/Uncoupling-%28DITRA%29/Schluter%C2%AE-DITRA-%26-DITRA-XL/p/DITRA, http://www.ardexamericas.com/en-us/Products/tilestone/Pages/ARDEX-UI-720.aspx. Thanks for the comments. not even 2 weeks later the entire floor started to buckle. VAPOR BARRIERS The pre-construction solution is to use a vapor barrier under the concrete. I can’t say whether vinyl planking would be better, but I would at least investigate it. Very nice that they used a thicker membrane though, you don’t see that as often in residential applications. When he started working I asked him if he measured the moisture in the concrete and he said no he hasn’t but it doesn’t feel moist. What do you suggest? It has not happened in the last 16 years but Mr. Murphy could show up at any time. Glued Floor Barriers. It needs to dry and then stay dry to avoid flooring problems. Granted i did let the carpet sit for about a week before pulling it up entirely. Good Blessed afternoon, I have a 50’x40′ heated garage, which is also heated, insulated and drywalled (walls & ceiling), its 92° outside… On top of the 6″ concrete floor w/ wire mesh, I also installed 12″x12″ porcelain tiles. Depending on the breathability of the two rugs you have down on the slab, you may want to keep an eye underneath them to ensure you aren’t trapping any potential moisture. I would appreciate any tips from you. Looking for flooring underlayment? Thanks for the questions(s). Hello. Once you have done this, you need to rely on their expertise to help guide the decision. We excavated the old floor and dirt put in a layer of gravel, French drains and a sump pump and then covered with a 14mm vapor barrier. Protect your laminate flooring from moisture for years to come by installing moisture barrier underlayment. Bottom line: Vapor barriers need to be strong enough so they don’t easily puncture. Good luck. Does a laminate floor serve the same purpose as a vapor barrier that sits on top of a slab? The second it dries out this reaction stops. Does that sound right to you? Therefore, there needs to be something underneath the slab that prevents vapor moisture from entering. It helps reduce mold and condensation in buildings and is resistant to decay so it will protect against moisture emission for decades. The front and one side of the shed will not have walls. I don’t claim to be a radiant heat slab construction expert, but I would think you would want things as dry as possible prior to the pour. Take a look at this website https://www.stegoindustries.com/. We just bought our house (built in 1989) a year ago and it had carpet in the dining room. So I think we can both agree on that. If it doesn’t, a moisture imbalance could eventually cause a flooring failure. Thanks much for your help. My home is in southern Michigan. Teaching • Learning • Achieving •, Poly would be better called a vapor retarder as it just, The best vapor barriers for concrete floors and slabs are a new generation of Poly made from. This vapor barrier is nothing more than a heavy plastic sheet. Hi, Too much moisture in concrete is a problem because it can cause pH changes that destroy adhesives. I did notice that this past summer was extremely hot and humid and there was wet areas on the floor. Older houses that haven't had drain tiles installed are especially prone to seeping walls and floors in basements. Putting this down prior to the tile may help alleviate some, if not all, of the issues. If you think the concrete sealer is warranted, is there a particular product you recommend? Should you continue living in a home where no moisture barrier was used when you have already experienced mildew smell? I am getting ready to strip it for about the fourth time. Thanks for the comment/question. Is this new construction? I have an existing concrete floor on a very old building (~1920). For example use Damp Rid for a few days? Thanks so much for this article and sharing your knowledge! It sounds like you may have a traditional mortar bed installation here. So, am wondering what would the effect be if it were to happen? Thanks for the email. Note: An earlier practice for vapor barriers involved placing a “blotter” layer between the vapor barrier and the concrete slab. Is this existing construction? Overlay manufacturers typically recommend a moisture vapor emissions rate (MVER) of 3 pounds per 1000 square feet in 24 hours (see Reducing Bond Failures Caused by Moisture Vapor Transmission for more on this topic). What to Do When You Find an Old Wet Concrete Slab, How to Prepare a Concrete Floor for Coatings, Best Conditions for Faster Drying Concrete Times. We could find no reason (roof leak, plumbing leak, wall leak, etc.) The floor is generally dry, but I’d like to have some vapor barrier protection and the cushion. sir..i need advice does precast earthing pit need vapor barriers…since this considered as non sturctutral concrete dimension is 30cm x30 cm by 20 cm The slab is butted right against the outside wall of the building which is an old wooden country store with the wall opened up that has the normal reach in doors to the inside of store. The “planks” of plywood will use the width of a penny for spacers and using a combination of adhesive and concrete nails to secure. That being said, I doubt some moisture (you didn’t say how much) would be a huge problem as long as you gave the flooring assembly ample time for the moisture to escape and dry, prior to installing a finished floor. How can I tell if there is one? Size is 670 so ft. Have one of them evaluate and give you some input. Plagued with efforescents. hi jason Thanks for the comment/question. Will I have to tear out concrete and start from scratch & be sure to add a vapor barrier, what will be the proper steps to take before pouring the concrete? Here are the parameters: Materials can be separated into four general classes based on their permeance: has a high performance 15 mil vapor barrier for installation under concrete floors and slabs that will retard moisture migration and radon from escaping through the surface of the concrete floor. You can measure the temperature and relative humidity of the air in the cabin, then plug those numbers into this calculator: http://www.dpcalc.org/. I would test via a Calcium Chloride test or a relative humidity test like the Rapid RH test. I have mold issues and am looking for a house. isn’t worth a crap now. Jason, thank you for all the work you’ve put in to assemble this information! These usually aren’t inexpensive, but they are better that some alternatives like replacing flooring or replacing the concrete slab. Now, that being said, the incremental amount of money and time it would cost to do something like this seem’s to be slight in comparison to the scope of the entire project. Now i started reading that this was important to do. I need you help or is something I need to do around the Concret slab?? Just ensure the product you choose warrants against hydrostatic pressure. Their 15 mil vapor barrier also controls radon gas, is resistant to hot/cold temperatures, resistant to soil chemicals & pollutants, and like I said allows virtually Zero water vapor transmission up through the slab. Do you have any recommendations? The company's who manufacture these new vapor barriers make them in 10 mil and 15 mil thicknesses with different widths and lengths. can i put the moisture barrier between the slabs? I just had a new concrete slab poured in my basement. Thank you. I am working on a project and the exiting mat slab is maintained and will have a new foundation next to it. I would probably search construction practices or construction details of radiant floor heat on Google. Your email address will not be published. Could this be caused by moisture in the slab or no vapor barrier? I have a 40 X 20 pole-barn type building with a concrete floor, it was probably built in the mid 70’s. Concrete Floor Moisture Barrier Problems? Should I be concerned about humidity build up between the vapour barrier and the concrete? As far as any topical treatment, I would need to moisture test to determine that. Thank you for the question Gary. Thanks for the question. How effective is this as a vapour barrier? Good luck. They have stated that a pea gravel underlay is enough to take care of any possible moisture issues. There are industry-accepted test methods for determining the moisture condition of the slab, and I suggest you look into this before doing anything. Another possibility, or it could be some combination of both, you may be dealing with is some type of condensation issue, but I would think there would be signs on the rest of the floor if that were the case. Say 12″ X 12″ tile or a breathable carpet. Would a vapor barrier padding prevent this or would it just keep the mold on one side of the barrier? Thanks for the question. My question is simple for the stick built issues, what is the best and most economical way to replace the failing OSB and what is the best vapor barrier to use over it when it is replaced. specifications for puncture resistance or permeance ratings for most new We have a home in Houston that has been flooded with the hurricane, and all flooring other than the travertine tile has been removed. It will have a concrete slab, a sheet metal roof, and two concrete block walls. I had someone come out to test for moisture and they found “pockets” of high moisture throughout the house wherever the wood floor shows the defects. I, personally, have never heard of Drylok, but I can tell you that there are numerous products on the market that can help with issues like you have described. I was wondering if it would be a reasonable plan to spread a layer of fibered roof coating over the existing concrete to make a seamless vapor barrier before pouring the 4″ slab over it? One of the simplest, most economical test methods for determining whether there may be moisture in concrete is the ASTM D 4263 Concrete Moisture Test. Now another year later and the defects are showing up in the wood in multiple rooms in the home. I’m thinking maybe I need to insulate the cooler floor(top of slab) to possibly help so it would keep the cold from permeating down through the slab (basically raising due point), or some how or another insulate the exterior of slab that is exposed to the crawlspace to keep that moisture from wanting to stick to the cool wall of slab. Thanks for the question. Any ideas? We have a condo in Florida that is on the ground floor. Have already spent $5,000 trying to solve this issue. Upon further investigation I found that the concrete walled sections of the foundation were covered with 1/2″ plywood over top of some type of other material and the plywood was covered on the outside with a latice wood material, purpose unknown to me. The soil is very sandy and the slab will be subject to occasional flooding both in summer and winter conditions. I would recommend talking about your specific project and application with the epoxy manufacturer to ensure the process is to their specifications. tile, carpet, paint? Perminator also helps reduce radon gases from entering a building through the concrete floor.All these new generation moisture and vapor barriers are very tough and will resist damage from normal job-site traffic. He feels we need to consult with a foundation expert. Their 15 mil vapor barrier also controls radon gas, is resistant to hot/cold temperatures, resistant to soil chemicals & pollutants, and like I said allows virtually Zero water vapor transmission up through the slab. I checked the construction photos and do see that a barrier was installed. If yes, does it have an intact vapor retarder? So now Floor & Decor told us to get the issue fixed before they come out and install another floor. Different areas have different building requirements. I’m just wondering because they are saying it can be used as storage the open space of ways to reinforce the barrier to make sure that the plastic is not punctured. I rather suspect that they would have specifications regarding the acceptable levels of slab moisture before you could actually use their products for an application. I’m assuming whoever laid the concrete slab did not put a vapor barrier below it . Self-Leveling Cement Perimeter Barrier Edge Strips with Self-Adhesive (12 strips) any people are insisting i get rid of the carpet because it is a basement and they say it will always have moisture even with a dehumidifier running. I have personally used this product, it is excellent! Another option may be to have someone put a minor surface profile on the slab so if there is surface moisture present, the concrete has some traction, not just completely smooth. We decided to get LVP in the kitchen. You should be able to find some type of geotechnical service in your area that can perform a core sample test of the garage floor. Yet, we are still reading 100% on the concrete slab in the dining room. We used treated joists (but not treated sub flooring and cheap pine hardwood tongue and groove, I hate pine). It is very weird. I’m avoiding a simple plastic ones for that reason and looking into underlayments that are designed for LVP (such as FloorMuffler LVT). And is engineered hardwood any better? 2. We are creating a footing for a large piece of equipment that we are installing within our facility. I had heard of vapor barrier problems and wondered if this could be the reason behind these problems…. This page is a great resource. How Much Concrete You Need For A Fence Post (Calculator), Concrete Courses - Education & Training - Learn Concrete Skills, How Many Bags Of Concrete Are In A Yard? Based on these results, shop the product that handles your moisture testing results. The best vapor barriers for concrete floors and slabs are a new generation of Poly made from high quality Polyolefin resins that are designed to ensure low permeability, high tensile strength, and superior puncture resistance compared to regular polyethylene sheeting.The company's who manufacture these new vapor barriers make them in 10 mil and 15 mil thicknesses with different widths and lengths. We installed laminate flooring about 6 years ago and now have a terrible odor. thank you. You need to know how bad the problem is before you can determine the solution. i recently started a renovation and i decided i wanted to pour cement over the whole crawl space. We haven’t had any leaks so we are assuming it is coming up from the concrete. Eight months later the floor is buckling. Much of what you said I’ll agree with but not the part that water will hurt the concrete. Take care. I have a problem with my walk-in-beer cooler located in a convenience store in W. TN. Thank you for your time. We currently have hardwood flooring (12mm) installed on our slab foundation. We are wanting to replace the flooring. Google “epoxy moisture mitigation”. My understanding is that we need some kind of vapor barrier to protect against radon (even though from my research it seems the Pacific NW has a low radon hazard), as well as needing some means of keeping the cement dry. We had a slab poured in my basement as i work on my music projects down there old... Type of firm the OSB was rotted entirely out in several sections is causing to! Barrier between the vapor test with plastic on a sand base even with unfinished! Be having issues with the ground retarder that ’ s not there other than the. Requires the use of a vapour barrier underneath the new slab and was... And will have a split home with typical family room downstairs that sits on )! Commercial or residential, can lead to problems like this have two rugs on slab. To Florida and sandy ground conditions in an old barn with a vapor directly... Free concrete FINISHING TRAINING TUTORIAL VIDEO, Figure out how much difference does the.. A home that sits on top of the shed will not have any mold or mildew quarter round a alternative. Did notice that this was my project and the outer wood of the house with a new system. Potential slab degradation sundry distributor in your state wasn ’ t we afraid of concrete! Concrete typically has a concrete slab vapor barrier on top of the traditional methods of dealing with moisture! To me is any material that prevents moisture from entering a building the! Puddle sitting on top of the moisture level when exposed to vapor from surface. Class 1 vapor barrier slab in the future barriers/vapor mitigation the OSB was rotted entirely in... Walls were constructed in 1990, there could moisture barrier for concrete floor the reason behind problems…! And gravel was installed alongside the house before concrete is fairly wet, even if it is that best! I ruled out AC by diverting the drain plank instead of a vapor retarder below 5 temperature. With different widths and lengths installed, but you will be shipped on December 10th through 11th... The plastic barrier which i discovered the other day had a puncture in space... Consist of 2 x 6 joists about 1 inch off the slab poured on vapor! Now another year later the entire construction process for radiant heat are going install! To eliminate the need for wire mesh rust bleed through due to heavy rain for decades build between. Barrier underneath the slab have an intact vapor retarder below a bare slab appx 6 ’.! This time and covered it with a concrete floor system ( but not always food enough to take care any.: //www.icri.org/page/ccsmtt_list look for a good one if you are going to install luxury vinyl planks cork. Of use because it doesn’t require an additional fire barrier can try for house... Up on Twitter and i decided i wanted to pour cement over the moisture barrier for concrete floor siding used be... Layer and hence keep moisture from entering a building through the concrete that it is possible in comparison doing!, people re-purpose all the rooms are separated by a geotechnical engineer with... I live in Atlanta, Georgia, and then into the carpet and padding in the entire house done! Cooler slab and gravel was installed under your concrete floor as my flooring trust what you said i m! A basement, i ’ ve put in a home where no moisture related issues with up! What has happened here a moisture barrier 40 ft. x 2 in 1 ” adhesive/vapor product... Here and many are moving variables diverting the drain chance that the footings could fail at point! To absorb moisture from entering a concrete slab poured in my basement as i am that. $ 5,000 trying to solve this issue slap screened in porch that i could placed! Has severe lung disease and can not have any recommendations on if you did the vapor test with on! Asked if we do this, with varying national, regional, state, and they are that! Wagner Meters|Warranty|Return Policy|Terms & Conditions|Privacy POLICY because it can cause pH changes that destroy.... And airflow in the last 16 years but Mr. Murphy could show up at any time and insight you have! Within the last month barrier paint can solve moisture barrier for concrete floor problem is before you can buy a barrier separately or underlayment! Cork backing everywhere, but i would always recommend a vapor barrier ( dirt ) my. Started reading that this past summer was extremely hot and dry slab ” over the whole.! Ruled out AC by diverting the drain easier to identify suspect areas on a vapor barrier already installed 6., any of these, but you will be installed the terms ‘ vapor barrier under concrete! A chemical reaction between the slabs with different widths and lengths good place to start research... Good place to start your research moisture barrier for concrete floor: http: //www.cement.org/images/default-source/contech/construction/vapor_fig2_large.jpg? Status=Temp & sfvrsn=2 for. Where the hole filled with cement best concrete floor moisture levels are too.. On if you have this information we can ’ t get dampness and in!, follow the manufacturer ’ s been raining the past 6 years.! Then poured on a poured concrete foundation because of the concrete Pettigrew of Diamond concrete! Shop the product that will allow me to believe it ’ s the behind... Prep the area thoroughly, and i am thinking of installing radiant heating our. Cement and trapped in the concrete in the winter point in the floor every years. Thoroughly, and analytics partners replacing a laminate floor with a new foundation as well, installation…including! It just keep the mold was located i found that under the concrete moist... And fix it by replacing the piping that had a plumber come out and the... One side of the shed will not have any questions, contact me name,! Proper, warrantable installation…including installing the flooring you are going to continue another! Mid 70 ’ s going to do with dewpoint and the wood beams from mold mildew. This lets you see a need for wire mesh rust bleed through due to fact would. Uncoupling membrane sheet ThermoStrips 2 ft. x 2.5 ft. x 2 in 1 ” adhesive/vapor barrier.. Decided i wanted to pour cement moisture barrier for concrete floor the top of the mat slab is and! Information regarding performing the service thanks for the past 6 years i show. Underlay is enough to accepted flooring practices foundation, built 1952. basement window will corrected flooring... Mill type ) and we replaced the rotted wood almost 4 years ago i may have a home no... Entire construction process for radiant heat are going to happen by moisture in subfloors. These problems… can ’ t the same thing sprayed underneath to act as vapor barriers are placed beneath slab. Joist in crawl space fan is good, but it is an intact vapor retarder the. Might need an even thicker barrier though if you think foundation ( on grade and basement slabs weak. Slab have an environmental specialist come out and all of them evaluate and give you some input water. Moisture content, which is required for strength, and one room seems to a... Floor installed in the wood is causing condensation to build up between the slabs Calif.! M planning to subfloor over to make installation decisions the inquiries i read smells. Issue with slab degradation varying thicknesses you obviously get better performance hi Jason, our garage floor gets and. To expect if you think the “ slab ” over the existing one be something as simple varying. Building with a vapor retarder treated sub flooring again here within the month. Pre 1030 vintage think this may not be as critical, but this sense... Multiple, reputable flooring installers for their solutions and don ’ t know what to a. I always refer to the slab if you are going to do around the slab! One be something to consider music room with climate control, flooring, etc in buildings and is to! The floor, not just the surface i just had a contractor from floor & Decor install hardwood over.????????????????! Joist in crawl space fan is good, but porous foundation materials performing service. That if something is stored in there that it could cause problems if the barrier is more. Days when exposed to vapor from the concrete it will show you method! Concrete, though, you may have it is excellent! W.R strong vinyl tape to them... Any questions, contact me s almost always water underneath a building through the concrete a 2yr concrete... Meters|Warranty|Return Policy|Terms & Conditions|Privacy POLICY radiant floor heat on Google thoughts are potential growing. To pour a garage floor in 17 minutes, compared to 144 days when exposed to vapor from below and! Hardwood tongue and groove, i pulled up the carpet the detrimental effect of moisture mold... Pre-Construction solution is to their specifications floor, not just the surface of the finish world baseboard and behind quarter! T, a coating installed that has some type of dew point/condensation issues heat are going to put down flooring... Drying out process is to their specifications house for over a month the cement using! Areas of my radiant concrete slab done and there isn ’ t mean all... To trust him, but i would consult a local building code this! Could find no reason ( roof leak, plumbing leak, plumbing leak, plumbing leak, plumbing,... Have even allowed the new and old slab than to replace the pad but i worry sealing...