Are old concrete floors usually porous? Concrete slabs that are of poor quality or have deteriorated over time may show excessive amounts of porosity. While these slabs can be polished, it may be more expensive to achieve an aesthetic polished concrete finish.
Is concrete floor porous? Concrete, by nature, is a porous material. In fact, if you examine concrete under a microscope its appearance closely resembles the appearance of a kitchen sponge. For this reason, untreated concrete surfaces are prone to staining.
Can moisture come up through concrete? Humidity—warm and humid air condenses into surface moisture when it comes into contact with the cool surface of your concrete floor or slab. Faulty/Missing Vapor Barrier—moisture from the ground can seep up and through the concrete.
Can damp come up through a concrete floor? Damp from the ground can make its way into your concrete floor. Due to concrete’s porous nature, it can then travel through it, causing issues in the flooring above. … Dig up the old concrete floor, install a new damp proof membrane and lap up edges before replacing the concrete slab.
Are old concrete floors usually porous? – Related Questions
What does ammonia do to concrete?
Diffusion of ammonia gas from the concrete will also render the concrete more porous and permeable and thus more susceptible to further attack from ammonium sulphate solution [14], [15].
What happens to concrete in an earthquake?
Seismic safety experts long have warned that brittle concrete frame buildings pose a particularly deadly risk during a major earthquake. … Concrete starts falling out of a ground-floor column. Then the columns flex, and the upper floors come crashing down, sinking into a cloud of dust.
Should i put gravel under new concrete?
Whether you pour concrete for a walkway or patio, a strong gravel base is required to prevent the concrete from cracking and shifting. Gravel is especially important in clay soil because it doesn’t drain well, which results in water pooling under the concrete slab and slowly eroding the soil as it finally drains.
Do hooks stick to concrete?
If you want to hang something from a cement wall, try using adhesive hooks so you don’t have to put a hole in the wall. Choose a hook that’s rated to hold more than the weight of the object you are hanging.
Can you use plastic anchors in concrete?
Plastic anchors protect walls and wall hangings. … Also called expansion anchors, they reinforce a screw in the wall surface so it can’t easily be ripped out. Wall anchors can be used in drywall, concrete, brick, metal or wood, and installation takes just a few steps.
How long for quick set concrete to set?
Quick Set Concrete attains initial setting in no more than 15 minutes under normal conditions and should be placed immediately upon mixing. Leave at least two hours after setting before applying any load.
What is the reason concrete pool walls are so thick?
The thickness of the concrete and rebar depends on the environment because the pool has to be able to withstand the forces pushing against it (soil outside and water inside). To be structurally sound, a concrete pool shell should generally be 6 inches thick.
Do you pour cement or concrete?
Although the terms cement and concrete are often used interchangeably, cement is actually an ingredient of concrete. Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. Concrete gets stronger as it gets older.
Can oscillating tool cut concrete?
By adding a carbide grit oscillating tool blade, you can use your oscillating multi-tool to cut and shape concrete. You can also use the device for jobs like grout removal.
What is the largest size of concrete paver?
By adding a carbide grit oscillating tool blade, you can use your oscillating multi-tool to cut and shape concrete. You can also use the device for jobs like grout removal.
How much does a concrete pump cost to hire?
Concrete pumps are rented by the hour. Generally speaking, hourly rates will range somewhere between $150 and $200. Prices will vary based on region and the amount of competition in the area. Most rental companies will require a minimum rental time.
What is chipping mix concrete?
Concrete chipping is a process which requires trained chippers or a robotically-controlled machine with an Ultra High Pressure water source (20,000 psi) to enter the drums of ready-mix concrete trucks and central mixers to break away the dried concrete along the drums’ walls.
What grit do you use to sand concrete floors?
For basic sanding, use sandpaper with the grit between 40-60. To remove minor irregularities, use 80-120 grit sandpaper. For perfect finish and smoothness, use superfine sandpaper with grit ranging between 200-400. If there are severe imperfections, then you need to use a floor grinder or special diamond disc.
How many cement bags in m25 concrete?
How many cement bags required for M25 concrete. Ans. :- 11 bags of cement required for 1 cubic metre of M25 concrete. Ans. :- 11 bags (0.385 m3, 554 kgs) cement are required for 1 cubic metre of M25 concrete.
Can i have foundation concrete work at snow?
Concrete is very resistant to cold. Its freezing point is around -2.78°C (27°F). … As such, the concrete must be protected until it reaches 500 pounds per square inch (psi). Since some freeze-thaw cycles occur during the winter, concrete protection must continue until it reaches 1500 psi.
How to make a concrete base for a garage?
The base itself should be 4″ thick in the main and 8″ thick around the outer edges. Underneath the concrete there should be a minimum 4″ of compacted hardcore. The edges of the base should be troweled off or chamferred to allow any water to drain off. Overall the base should be 3″ bigger than the building on all sides.
How long does a concrete sidewalk take to cure?
Your concrete should be solid enough to walk on, without leaving footprints, after anything from 24 to 48 hours. By seven days, your concrete should be cured to at least 70 percent of its full strength.
What does sulfate do to concrete?
Sulfate attack of concrete is a complex process, which includes physical salt attack due to salt crystallization and chemical sulfate attack by sulfates from soil, groundwater, or seawater. Sulfate attack can lead to expansion, cracking, strength loss, and disintegration of the concrete.
Is polished concrete slippery outside?
While concrete is an extremely durable and versatile material, the downside to a high polish is that it can make the concrete surface slippery when wet, meaning it’s not ideal for use in outdoor areas that might be exposed to wet weather.
What’s better concrete or asphalt driveway?
Concrete is more durable than asphalt. Because it is a less flexible material, it cracks in freezing temperatures, and many people turn to concrete patching products. Concrete offers 50+ years of use. The only maintenance required is occasional degreasing.
Do i need sealer for concrete wall?
Although a concrete wall does get wet, water doesn’t pool on it like it does on flat work so it doesn’t need sealing as much. After concrete has been poured and cured, adding a sealer helps protect it from future damage, corrosion, and stains. Because concrete is porous, it tends to absorb water and other substances.