When did asbestos stop being used in concrete? For a post which is 48 inches (1,220mm) high from the ground level, the depth of the foundation base will be 30 inches (762mm) from level ground. For a brick boundary wall or screen wall, the depth depends on soil conditions (the load bearing capacity of the soil) as well as the load of the superstructure.
How deep does a concrete foundation need to be? Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. Footings also must extend at least 12 inches below the frost line (the depth to which the ground freezes in winter) or must be frost-protected.
How deep do excavation for foundations need to be? Generally a depth of 700mm is acceptable, as long as the ground has adequate bearing capacity. If the water table is high (for instance if the gravel is submerged), the bearing capacity will be halved, so it’s important to keep the foundations as high as possible.
How deep should foundations go? Foundations should be placed at least 450mm below the finished ground level to avoid the risk of the bearing strata freezing and causing damaging movement.
When did asbestos stop being used in concrete? – Related Questions
What is a cold joint in concrete?
For a post which is 48 inches (1,220mm) high from the ground level, the depth of the foundation base will be 30 inches (762mm) from level ground. For a brick boundary wall or screen wall, the depth depends on soil conditions (the load bearing capacity of the soil) as well as the load of the superstructure.
Do you have to acid wash concrete before staining?
Schmidt also warns against acid etching of floors before staining. A lot of people think they need to acid etch the concrete like they do before applying a paint or coating, to get the paint to adhere. But acid washing depletes the lime content, which is what the minerals in the acid stain react with.
How long to keep fresh concrete covered when cold weather?
Schmidt also warns against acid etching of floors before staining. A lot of people think they need to acid etch the concrete like they do before applying a paint or coating, to get the paint to adhere. But acid washing depletes the lime content, which is what the minerals in the acid stain react with.
Why use a wood float on concrete?
Wood floats rough up the surface of concrete more than does magnesium, almost forcing moisture to the surface while opening the surface up (or increasing porosity) for surface applications of color, hardener, etc.
Is exposed aggregate more expensive than stamped concrete?
Both stamped and aggregate concrete are cost-efficient. Compared to other methods, they are more affordable. … Stamping is not expensive, but using aggregate concrete is more economical, especially if you have a larger project. Typically, stamped concrete starts at $120 while an exposed aggregate finish is around $100.
What is needed under laying laminate over concrete?
Laminate flooring manufacturers recommend waiting at least 60 days for concrete to cure before you lay laminate over it, but even then, you need a minimum 4-mil plastic vapor barrier.
Can you raise a concrete floor using plywood?
Yes you can. Ive done it many times, usually in days gone by when one wanted to nail a tongue and groove wood floor down. These days, you can glue woid floors directly to concrete. If you just want to raise the floor level, you can also glue the plywood down to the concrete.
How many wheelbarrows in a meter of concrete?
There are approximately 20 barrow loads of concrete per m3. this is based on a standard one wheel barrow, loaded to 80% capacity.
Do you need to seal exterior concrete before painting?
Yes, you should always seal concrete before painting it. This is pretty easy to do, as long as you have a good quality primer. It’s an essential step of the painting process that shouldn’t be overlooked. The primer is used to fill any small gaps, cracks, or voids in order to create a smooth and uniform finish.
Why has new concrete cracked?
Shrinkage is a main cause of cracking. As concrete hardens and dries it shrinks. This is due to the evaporation of excess mixing water. … This shrinkage causes forces in the concrete which literally pull the slab apart.
Is it bad to put salt on concrete?
The answer is yes, salt does indirectly damage your concrete driveways, patios and sidewalks. Bumps and potholes don’t just appear due to regular wear and tear – salt damages concrete over time by causing corrosion to occur under the surface, leading to discolored, cracked and crumbling concrete.
Are concrete floors expensive?
Costs can range from $2 per square foot for a basic to $30 or more for high-end artistically rendered floors. Basic design: $2 to $6 per square foot. … MId-range design: $7 to $14 per square foot. This price range includes pouring the slab or overlay, then polishing and staining with multiple colors.
What type concrete for footings?
C25 is often used when pouring foundations (footings). It is also the ideal concrete for domestic slab foundations for house and bungalow floors.
How long before removing form around concrete?
For Concrete Forms, Concrete walls and concrete columns can be removed after about 24 to 48 hours. 2. Slabs, with their support left under them, can be normally removed after 3 to 4 days.
Can you pour concrete over asphalt millings?
For Concrete Forms, Concrete walls and concrete columns can be removed after about 24 to 48 hours. 2. Slabs, with their support left under them, can be normally removed after 3 to 4 days.
How long before pulling concrete forms?
The forms or “molding” that holds the concrete in place until it dries should be left alone for at least two days to ensure that the concrete is completely dry. If the forms are removed too soon, the concrete can begin to sag, crack and collapse, especially if conditions like temperature affected its strength.
Where in the slumped concrete should the measurement be made?
The mould is carefully lifted vertically upwards, so as not to disturb the concrete cone. The concrete then slumps (subsides). The slump of the concrete is measured by measuring the distance from the top of the slumped concrete to the level of the top of the slump cone.
How much is architectural concrete?
Prices can range from $2 per square foot to $7 for a basic application. Average price for a new concrete slab with remedial cleaning required and basic pattern with a standard residential grade sealer is about $3 – $5.
What is shotcrete concrete?
shotcrete, also called (trademark) Gunite, concrete applied by spraying. Shotcrete is a mixture of aggregate and portland cement, conveyed by compressed air to the nozzle of a spray gun, where water is added. The wet mixture is then sprayed in place and may be carved or troweled almost immediately.
What happens if concrete is not cured properly?
When concrete is not cured properly, its durability, strength and abrasive resistance are affected. Due to inadequate curing, concrete develops plastic shrinkage cracks, thermal cracks, along with a considerable loss in the strength of the surface layer.
What do i need to grind a concrete sidewalk?
If you need to refine the surface of an outdoor sidewalk, work your way through the grit levels of your discs: from 18 grit right up to 120 grit. Any of these large grinders can be paired with an edge grinder to get into those tight spaces.