Contents
- 1 When should you float concrete?
- 2 What is a floating concrete slab?
- 3 What is the purpose of a floating slab?
- 4 What is the difference between a trowel and a float?
- 5 How long after pouring concrete can you power float it?
- 6 How do you prepare a floating slab?
- 7 Does a concrete slab need footings?
- 8 Do you need rebar for 6 inch slab?
- 9 Do you need gravel under concrete?
- 10 Why do you use a magnesium float on concrete?
- 11 What defects can be caused by bull floating too soon?
- 12 How do floating foundations work?
- 13 Does a floating slab have footings?
- 14 What is a floating garage?
When should you float concrete?
Float the concrete when you‘re done grooving and edging (Photo 6). Floating removes the marks left by edging and brings the surface one step closer to a final finish. You may have to bear down on the float if the concrete is starting to harden.
What is a floating concrete slab?
The term floating slab refers to a two-stage slab construction, where footings are individually. poured, and the centre floor of the slab is poured after footings have cured. The forms of a monolithic slab are designed so that both footing and slab floor are poured at the same time.
What is the purpose of a floating slab?
Floating slabs behave as a barrier for the entrance of the moisture coming from the ground. It acts a barrier between the superstructure and the ground. This avoids seepage of water and frosting. For this purpose, the slab can be insulated for frost or moisture.
What is the difference between a trowel and a float?
A float has a thicker base than a trowel and is usually made of plastic, sponge, rubber, wood or magnesium – a lightweight pale grey metal. It’s used to even up the surface on plaster or concrete, make it firmer and give whatever texture is required.
How long after pouring concrete can you power float it?
Allow all of the water to disappear before you do anything else. This can take 20 minutes or 4 hours depending on the temperature, humidity and how hard the wind is blowing.
How do you prepare a floating slab?
- Determine the area for your floating slab and mark the four corners with 3-foot metal stakes.
- Determine the height of the top surface of your concrete slab.
- Measure out two feet from the perimeter (laterally) and mark off this area for drainage.
- Measure down 2 feet and 11 inches from the perimeter strings.
Does a concrete slab need footings?
While not a requirement, a concrete slab foundation provides a solid, clean surface for your steel building and can help it last longer. Since the building will require anchoring to minimize shifting, pouring a concrete slab gives you a chance to pour footings as well.
Do you need rebar for 6 inch slab?
Rebar is recommended for concrete that measures 5-6 inches in depth. The type of and intended use of concrete impacts the need for rebar reinforcement. Rebar must be placed at the center of or slightly above the center of the concrete slab—hence why it should be a certain thickness for best results.
Do you need gravel under 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.
Why do you use a magnesium float on concrete?
Magnesium smooths the surface of fresh concrete and opens the pores for proper evaporation, all without pulling the surface like a wood or resin tool. Most magnesium floats are extruded or cast. Molten magnesium can be cast into any shape desired.
What defects can be caused by bull floating too soon?
More often, premature finishing or improper first (bull floating) or second floating results in trapping rising bleed water and air below the top surface of the concrete (Image 2). When this occurs, the resulting weak or soft zone below the surface causes the top surface of the concrete to flake or scale off.
How do floating foundations work?
A floating foundation consists of boxlike rigid structures set at such a depth below ground that the weight of the soil removed to place it equals the weight of the building; thus, once the building is completed, the soil under it will bear the same weight…
Does a floating slab have footings?
Answer: A floating slab foundation is a foundation which doesn’t have concrete footings. This allows for the garage floor to just be poured over gravel and the existing ground.
What is a floating garage?
What is a floating slab? A floating slab is a concrete slab foundation on which a structure is built. A floating slab does not have frost protected footing and is designed to “float” with the ground during the winter months. Floating slabs are most commonly used when building a detached garage or shed.