Pouring concrete over existing concrete slab - How to bond them together 
Q: What are the best techniques for raising a concrete floor? I'm enclosing an 11'X13' area of my garage to make a new room in my house. I'll be pouring …

How to fix peeling epoxy paint on a basement floor 
I used an epoxy paint last year in my basement (typical tan with brown and white paint chips). But then had some water issues. Parts of the paint have …

Strange white powdry spot that seems to grow as it pits the slab? 
I have a slab . This 12 inch round spot appeared. its literally eating the concrete. i have washed it with water and pine sol. I have used baking soda …

Self leveling concrete 
Q. I have a 400 sf unfinished crawls pace that I use as an unfinished basement due to its high ceiling height of over six feet. The only thing on the …

How to make concrete pavement interlocking bricks 
Q. What are the mixing ratios for concrete pavement interlocking bricks? A. If you are going to mix the concrete to make your own concrete pavement …

New home with 2" thick concrete slab in basement 
Q. Ive been living in my new home a little over a year now and have noticed the cracks in the basement floor worsen. Some cracks are almost 1/8 thick …

small cracks in stained concrete floors 
Q. I have stained concrete floors which have developed small cracks. Can I fix these without ruining my floors? A. Small hairline cracks are a normal, …

How do I re-seal a concrete floor 
Q. We stained and sealed our concrete floor in our new house. I think we did this too soon, and the floor has been scuffed, scratched, and spotted during …

Concrete shed foundation on a slope in cold climate 
Q. I live in Toronto Canada where we have a cold winter. Sometimes it could be down to -30C. I planned to build a garden shed in the size of 12' x 8' …

Drilled through foundation and vapor barrier into dirt Not rated yet
hello, we were having a humidity test done and the large drill went through our foundation and through the vapor barrier into the dirt below. how is this …

How do you clean interior unsealed concrete floors after drywall has been put up Not rated yet
I didn't think of laying plastic down when they put up drywall until after they were done. This is a finished basement apartment which is 3/4 under …

How to fix a low spot in my Spancrete garage concrete floor Not rated yet
Q. I have a Spancrete garage with a workshop underneath. There is a low spot near the floor drain where lots of water will puddle. Is there a product I …

Cut Concrete With Radiant floor heat Not rated yet
Q. I am looking to cut a trench into concrete at a carwash location that has radiant floor heat. Is there a way to accomplish this without completely …

Concrete Slab for Pole building Not rated yet
Question: I am going to build a Garage/Workshop standalone away from house 40x30, Pole/wood frame & metal siding & roof. What would be the right thickness …

How to determine volumes of sand and stone when relaying a 4" concrete floor over an existing damaged concrete floor outside a church building Not rated yet
Q: Sir, I have been tasked to spearhead the laying of a 4" concrete slab over an existing damaged outside floor of my local church. our first task is …

Can you install radiant heating to an existing concrete floor? Not rated yet
Q: My husband and I are looking to refinish a room in our modified split level. This room has a side door and is very cold. Right now there is carpeting …

How & can I change acid stain color on my concrete mantle? Not rated yet
Q. I had my fireplace mantle made of concrete, acid stained and sealed with an acrylic (water base?) by a contractor. I am very unhappy with the moderately …

Color or stain existing concrete floor Not rated yet
Q. I recently purchased a place that has concrete flooring over in floor radiant heat. Can I paint or stain this existing floor? A. Yes, you can use …

White fuzz or powder appears on the concrete surface Not rated yet
Q. Why would a "white fuzz", I am assuming its a mold, grow on my concrete floor in my shop, in any area, after water has been on it and dried? A. …

Sealer for Black Concrete Not rated yet
I have black concrete which has had oxide put into the pour to make it pitch black. However after it dried the colour intensity is nowhere near as black …

Polished concrete floor mix with glass Not rated yet
Q. What concrete mix is best for a polished interior floor and would you change the mix if adding pieces of coloured glass to the surface after pouring …

heating slab floors in homes Not rated yet
Q. My house was built in 1950 on a slab. I would like to put some radiant mats under my bath room tile floors. I have wood flooring in my kitchen...What …

Air bubbles from the concrete slab. Not rated yet
Q. My garage slab is about five years old. I was washing it and air bubbles appeared where I was washing. What is causing this? Should I worry? A. …

Figerglass Pieces Protruding From the Concrete Surface Not rated yet
Q. We have recently had a new concrete driveway and walk done where the surface has been brushed such that fiber pieces protrude above the surface. They …

Click here to write your own.

Hot Tub on concrete slab Not rated yet
Q. Is 10 days long enough for a 4" X 7' X 8' concrete slab to cure before I put a hot Tub on it ? A. If the concrete was 3000 psi concrete, came from …

Bathroom Concrete Floor Drain Not rated yet
Q. Hi! I am renovating a building ( or considering it) to open a bakery. As part of the local Sanitation Code, I am required to install a floor drain the …

Pouring a concrete floor on solid bedrock Not rated yet
Q. I recently bought an older house with a stone foundation that sits directly on solid bedrock. The size is 24' x 28' I occasionally get a little …

What kind of concrete to use for radiant heat concrete? Not rated yet
Q. What kind of concrete should I order for pouring on my main floor on top of radiant heat? A. We use 3000 psi concrete with 3/8 (peastone) stone …

How to stop moisture coming through concrete basement floor Not rated yet
Q. I have a 45 year old home with what once was a finished basement. We had a sump failure last summer. The floor and 2 feet of drywall was removed. …

Cleaning drywall dust off unsealed concrete floor Not rated yet
Q. A couple of years ago I had to replace my concrete foundation floor in my basement. At the time we made the decision to have colored concrete in place …

Can I pour concrete on my old wood floors? Not rated yet
Q. I have visited a friend, who had the concrete floors with the stones strategic placed through out the family room and kitchen. It was absolutely beautiful. …

Stamped Concrete in Three Season Room Not rated yet
Q. We are having a three season room built, probably 12x16. It will be about 4 ft high. They are only putting down subflooring and we get to put whatever …

Using Quikrete for a concrete patio Not rated yet
Q. I am going to pour a 10x12 concrete patio, and want to use Quikcrete. I will be reinforcing it with WWF as well. Do you recommend this product for …

Fresh Pour..Cleaning and Buffing.. Not rated yet
Q. Just poured a slab on top of a slab in my basement, 3 days ago. I have yet to do any cleaning to the surface. As it stands now I am not happy with …

Ratio for ready-mix sand and gravel to cement an water Not rated yet
Q. What is the ratio for ready-mix sand & gravel to cement and water? A. Check out my page about Concrete Mixing Ratios .

Paint for radiant heat Not rated yet
Q. What do you recommend for painting a concrete floor with radiant heat? Is this a possibility? Is there a special paint/process I should follow? Should …

Prepping concrete floor prior to acid stain Not rated yet
Q. My husband and I are finishing our basement and have chosen to do an acid stain on the concrete floor rather than tile or carpet. We had to bust out …

matching existing texture and color of concrete patio Not rated yet
Q. we are enlarging our patio, adding concrete to existing patio that is textured and colored. The existing slab is six years old, attempting to match …

bonding new concrete floor to just poured concrete garage floor Not rated yet
Q. I am having a new home built. The concrete people did the garage floor and my husband wanted a small pitch to the floor Needless to say when they …

carpeting on a new concrete floor Not rated yet
Q. How long after the concrete floor is poured can I put permanent carpeting down? A. Concrete takes 28 days to fully cure. While it is curing there …

What do you do if it rains while pouring a concrete floor? Not rated yet
Q. What about rain during a pour? Heavy/light, need to cover etc.? A. If it rains while you are pouring a concrete floor it is very important to cover …

settling basement floor Not rated yet
q. About 8 yrs ago I had a foundation company lift the footing around two sides of my house. We noticed just 3-4 yrs after, that our basement floor was …

what do you use under concrete? Not rated yet
Q. We are pouring our garage floor on a new build, what kind of material do we use under it? The builder currently has some recycled concrete but we need …

CONDENSATION OF CONCRETE SLAB Not rated yet
Q. Please could you inform me as to how should I specify that a concrete slab on which a raised computer floor that will be installed and shall be used …

unlevel concrete floor Not rated yet
Q. We had a 40'x12' concrete floor poured 4" thick with wire mesh and rebar over gravel with perimeter footings for a one story sunroom attached to our …

sealing concrete Not rated yet
Q. Hello, We're considering pouring a concrete basement floor and we heard about a type of concrete mix that contains a sealant. What is this? Do you recommend …

floating concrete patio Not rated yet
Q. If you use fiber cement do you need wire mesh for a floating concrete patio 20'x12'? A. We use just fibermesh for reinforcement all the time. We …

Stamped concrete patio Not rated yet
Q. Would bleach harm my outdoor stamped concrete patio? I have a pigeon who has made my patio his home and I want to clean the patio and bleach it to discourage …

Pouring Slab for Shed Not rated yet
Q. What thickness of slab is recommended for an 8x6 garden shed? Is 2" sufficient over a 1 inch screening bed? A. I would recommend 4" thick. Two …

Click here to write your own.

concrete over rock Not rated yet
Q. I am expanding my house, and one room has the canadian shield rock coming to within 2 inches of the finished floor surface. how would you recommend …

Is this concrete? Not rated yet
Q. I have a black hard floor in my house which was under the carpet in a home built in Ca in the late 50's. Is this hard black floor cement? A. Obviously …

Getting rid of protruding reinforcing fibers  Not rated yet
Q. What do I do to get rid of protruding fibers in my concrete floor before applying any sealers or any concrete finishes? A. Although these will wear …

3-season room floor Not rated yet
Q. I have a space attached to my home with a hip roof and three 4 x 4 wooden posts (roof supports) on concrete pillars that are approximately 3 feet into …

materials to be used on my concrete floor Not rated yet
Q. I am very much excited to do the project in my home. But I wonder where I can get these materials? How do I ask for the materials for the purchase! …

repair basement concrete floor Not rated yet
Q. We have just had two original furnaces replaced & the concrete floor was unfinished underneath them (the new furnace is located in a different spot). …

Behr Stain Remover Not rated yet
Q. I have Behr concrete stain on my large patio. It is peeling off over the complete surface. A new contractor says he thinks we need to grind the very …

Dyed Concrete Basement Floor and Bird Poop Not rated yet
Q. We just had a dyed concrete floor poured into our new basement. Before the house was set back down (from being jacked up while the walls were being …

water marks on concrete  Not rated yet
Q. How do you prevent water spots from sprinklers on stamped, stained and sealed concrete? A. The water spots are from the minerals in the water. …

Unheated floor in an ICF basement. Not rated yet
Q. I have a house with an ICF Foundation. There is a concrete floor and I would like to finish the basement. The concrete floor is cold and I am unsure …

What kind of paint/glue I should use on concrete? Not rated yet
Q. I am doing a renovation in my Aunt's home. I'm going to put a 3 inch wide and 12 feet long of marble on a couple of concrete. The concretes are already …

Preventing garage floor from cracking Not rated yet
Q. Whats the best method for pouring a garage floor to minmize cracking ,thicknes ,rebar ,prep,.thanks terry A. The sub-base must be gravel (18" to …

cleaning black mold from unfinished basement floor Not rated yet
Q. I covered my unfinished basement floor with a loose lay of linoleum (vinyl flooring from a box store). My basement took on about two inches of water …

concrete in canada Not rated yet
Q. I am pouring a concrete slab 8 x 10 foundation for a shed. i live in Ottawa Canada and am wondering if I have to put wire mesh in the concrete or can …

Building a porch and concrete stairs Not rated yet
Q. When building a porch/stairs, do you have to completely tear the entire stairs and porch down first and start from scratch. Or can I just tear the …

Is the color in my concrete integral? Not rated yet
Q. We are about to launch a big backyard renovation. We have a colored concrete patio but are not so sure that we like the current color. Any methods for …

Will outdoor carpet stain concrete? Not rated yet
Q. Will an outdoor rug stain the concrete? A. Yes, it's possible an outdoor carpet could stain the concrete. Depending on what the carpet is made of, …

Pouring concrete over wood floor Not rated yet
Q. I have took up my carpet and foam, cleaned my subfloor and I would like to pour cement. Should I put an anti fracture peel and stick membrane down …

How do you remove scuff marks from polished concrete? Not rated yet
Q. How do you remove scuff marks from polished concrete floors? A. Try a tennis ball or the souls of tennis shoes. Rub the scuff marks using as little …

Redoing a bad job on concrete staining. Not rated yet
Q. My contractor did a horrible job on staining my concrete. I have several spots (huge in width) that are uncolored and he said it was impossible to color …

Pouring a concrete slab for a hot tub Not rated yet
Q. I am pouring a 12x13foot slab for my hottub under my deck. I have scheduled a concrete pump trailer and 2 friends to help. I will be pouring in contact …

Will grass indoor/outdoor carpeting ruin concrete? Not rated yet
Q. If I do not glue my grass carpeting to concrete, just roll it out, will it ruin the concrete? A. No, the indoor/outdoor carpeting will not ruin …

Matching color on polished concrete and stamped concrete Not rated yet
Q. When adding a polished border on a stamped concrete patio is it possible to achieve the same color throughout. We are wrapping a 1400 SQ FT Patio …

Concrete apron for a loading dock Not rated yet
Q. I am planning to pour an concrete approach (apron) for a single dock position. The approach is sharp radius so the asphalt surface is getting destroyed …

Concrete contraction joints for pumped concrete? Not rated yet
Q. I heard hose pumped concrete shrinks more than that with large aggregate due to the use of pea gravel. I am pouring a 20x25 5 inch slab with 4/8 20 …

Click here to write your own.

Will the concrete be to heavy for a kitchen floor? Not rated yet
Q. Will the concrete floor be to heavy in the kitchen? I have a town home 3 level and the kitchen is on the main level, if i do concrete for the flooring, …

finish an existing stamped concrete patio Not rated yet
Q. We bought a 2 year old house with an awesome stamped concrete patio. It is a simple design with the veins running through it. I would like to darken …

Newly poured colored concrete Not rated yet
Q. We had colored concrete poured 1 week ago, when is it safe to put water on the concrete. We have bird droppings on it. When do we put sealer on it. …

concrete floor in crawl space. Not rated yet
Q. The tips of a couple of joists under the main floor have rotted off, due to moisture, causing the floor to sag a bit in a small area. I'd like to …

moisture on garage floor Not rated yet
Q. This time of year spring to summer I have moisture beads all over my garage floor on top of epoxy paint. I was told by a mason there is a vapor barrier …

Concrete instead of gypcrete for radiant heat floors Not rated yet
Q. I am building a house and want to use concrete instead of gypcrete for my radiant floor heating system. Can I pour concrete right on my sub floor or …

Concrete slab for a storage building Not rated yet
Q. How many bag of cement will I need for a 8x10 floor? A. If the concrete floor is 4" thick you will need about 517 pounds of cement. Cement usually …

How can i remove the dirt from the concrete stamped floor? Not rated yet
Q. We have a heated, concrete floor in our new four season room. After the floor was installed we had the room dry-walled. There is white drywall dust …

Installing concrete anchors Not rated yet
How soon can anchors be installed on fresh garage slab? A. If the concrete is a minimum of 3000 psi, you should be able to drill and install concrete …

Basement Slab Strength Not rated yet
Q. I am thinking of building a storm shelter / safe room in my basement. The shelter will consist of cinder blocks reinforced with rebar and filled with …

cleaning the color off stamped concrete Not rated yet
Q. I just got stamped concrete on my driveway. I picked a brown color and another lighter colored powder was added to release the stamps. I was assured …

Bolting safe to basement concrete slab Not rated yet
Q. I'm concerned about bolting a safe to the basement concrete slab. What if the slab is thinner than I thought it was or if I drill too deep and end …

4 ,1inch holes in basement floor Not rated yet
I HAVE 4 1 INCH HOLES THAT LEAK WATER. HOW DO I GO ABOUT FILLING AND WATER PROOFING HOLES AND SURROUNDING AREA? WILL A BONDING AGENT AND FLOOR LEVEL BE …

why is lemon juice used in concrete? Not rated yet
Q. Why is lemon juice used in concrete? A. Lemon juice is used to clean concrete not used in concrete. The natural acidity of the lemon juice helps …

Temperature Resistance of concrete floor Not rated yet
Q. I am planning on installing a walk in oven to dry aircraft parts. The temperature required to do this is 450 F. I have been told that the concrete …

How to pour radiant heat concrete floor over existing concrete floor Not rated yet
Q. Is there an answer to installing a heated hot water floor system over the existing concrete floor? How much room would you need to pour over and cover …

Cleaning water marks off of a concrete floor Not rated yet
Q. How do I clean water marks off a concrete floor? I recently put concrete floors in my home with a stain and a polished finish. Any time water drips …

how to clean stamped concrete basement floor Not rated yet
Q. We have a stamped concrete basement floor in the house we just built. It is the slate pattern. Our constructions workers were very careless with …

acid stained floors Not rated yet
Q. I am building a new home with ICF's and concrete slabs. How long do the slabs have to cure before they can be stained. Also, should I cut the slabs …

Will basement floor support small swimming pool? Not rated yet
Q. Thinking of putting in an Endless Pool in my basement. The pool holds 2600 gallons of water; the footprint is 8x13 (104 ft2) or 208.75/pounds per …

Dark Areas Around Concrete Cracks, Seapage? Not rated yet
Q. Our brand new home of only 2 years has a full basement with a concrete floor. It has cracks in it, but the other day we went downstairs and it looked …

cement floor with radiant heat with no drain or pitch in floor. Not rated yet
Q. Is there a way to install a floor drain without damage to radiant heat? thanks steve A. Without any underground drainage already in place …

Decorative Concrete Floor repair before staining Not rated yet
Q. We installed radiant floor heating in our house with concrete over the subfloor (tongue and groove decking subfloor with crawl space underneath). …

slippery garage floor in winter  Not rated yet
Q. My garage floor was installed 4 years ago and I was told the mason did a burn surface. Very bright and flat. When wet, especially in winter, we can't …

Newly poured floor chalky on some spots Not rated yet
Q. I just repoured a 11'X14' X 3" room in my basement on Sunday. It seems to be hard but there are a lot of places where it seems like wet chalk. If I …

Click here to write your own.

1950's pre-spancrete Not rated yet
Q. I've got a 1950's pre spancrete garage floor with a room underneath...How was this constructed? I'd really like to see a cross-section view. Does anyone …

How thick should a concrete balcony be? Not rated yet
Q. How thick should concrete be when used for a home balcony? I'm worried that the weight will be too much for the supporting 6" posts and 2x12 beams. …

1950's polished concrete floor slabs and brass inlay Not rated yet
Q. I have attached photos of our concrete floors in an old mansion we recently purchased. We do not think we can afford to have the floor removed, but …

Stamped concrete slab is sloped wrong way Not rated yet
Q. We recently got some concrete poured and stamped for our backyard entertainment area. It runs along side the house and attached garage and is slopped …

How do I install a drain in an existing concrete floor Not rated yet
Q. I am looking to install a drain in an existing concrete slab. How would I do this? A. Installing a floor drain into an existing concrete slab will …

waxing black concrete floor  Not rated yet
Q. I am just finishing up a house. I added a water based sealer (moxie 1800 admix) and color (Davis color called Graphite- essentially black) The floors …

Removing an oil stain on a concrete floor. Not rated yet
Q. I have a garage floor that has a 3x3 foot oil stain and I want to clean it up properly so I can acid stain the floor. What's the best way to do so? …

Patching concrete in basement floor Not rated yet
Q. We recently had our basement floor slab cut to install pipes for a new bathroom and laundry area. The builder filled the cut with hand mixed cement. …

Can concrete be used as indoor flooring? Not rated yet
Q. Can a stained polished concrete floor be used in a house that does not have a cement floor? A. If you are asking if a concrete floor can be installed …

Cleaning Deeply Embedded Gylcerol Spill from Concrete Floor Not rated yet
Q. There was a discharge of glycerol / glycol from a wet sprinkler system onto my unsealed cement basement floor. Unfortunately, due to insurance red-tape, …

ICF footings Not rated yet
First, I would like to thank you for an excellent website, very user friendly and detailed. Q. I'm what is known as a rookie who is adventurous. I …

Methods for coloring concrete Not rated yet
Q. What is the most common method for coloring concrete, is it mixing the color in the ready mix truck or casting color on top of the wet mix? thanks …

Removing old carpet glue on concrete floor Not rated yet
Q.Is there a product available that will cover old carpet glue. I've removed indoor/outdoor carpet from my concrete balcony. Glue is around the edges …

Hot to touch stamped concrete pool deck Not rated yet
Q. We have stamped concrete for our pool deck. Unfortunately, it gets scorching hot! We live in CT where it does not get that hot, even on a 75 degree …

Unsealed concrete Not rated yet
Q. Our floors in a flower shop processing area are concrete. Someone decided to use muriatic acid to clean them. Now the floor absorbs water very fast …

stamped concrete pool deck too hot Not rated yet
Q. We recently did stamped concrete for our pool deck and are finding it to be unbearably hot. Is there anything to treat this with so when you get out …

garage floor drain Not rated yet
Q. It appears your topic about installing trench drain or square drains is for new construction. Can they be installed in an existing garage floor? I …

should I use stone under my cellar floor Not rated yet
Q. I am planning to concrete my cellar and I get water sometimes. My cellar is dirt. Should I lay stone before I lay the concrete. A. Yes. First …

Concrete floor thickness and strength Not rated yet
Q. How thick should my basement floor be and what kind of concrete should we use? A. The average thickness for a basement floor should be 4". If you …