Construction of foundations is among the most commonly desired services from concrete contractors. You'll find 3 major foundation designs that are usually employed. These include: poured wall foundations, slab foundations and pier or pillar foundations. Briefly put, below is what these major forms of foundations entail:
1. Slab Foundations
They're very easy and economical and they are mostly preferred because they do n't need the necessity for major excavations, foundations walls or footings. 3 variants in the slab foundation exist, namely: cold area, wet warm area and desert. For all three, the region is often staked out with batter boards and the top layer of soil or sod is normally removed. Materials and tools used are very much like those used for typical pour slab foundations.
2. Pier and Pillar Foundations
Pier foundations are merely individual footers that are meant to support a structural beam or post. Simple pier foundations are often utilized for small structures that are built using a crawl-space design. Anchor plates and bolts are usually secured into place in the pier footer before the concrete fully takes hold. Attaching the beam or post is thus simplified and thus, leads to one of the most strongest of applications. Pier foundations are most of the time, set deep to the ground to avoid the upheaval and shifting processes brought about by perennial freeze and thaw cycles. To bring down the quantity of concrete that is utilized, a truncated pyramid shape is employed. Plywood or any other strong lumber may be used to construct the forms.
3. Poured Wall Foundations
Unlike block foundations, poured concrete foundations offer the advantage of possessing no joints or any weak spots. Through the entire foundation, no mortar or hollow openings are in existence. This ends in poured wall foundations presenting a number of advantages such as:
- Increased water proofing.
- Increased fire resistance.
- Design flexibility
- Ease of maintenance.
On the other hand, concrete blocks utilized to build block foundations are naturally hollow and they also tend to be vulnerable to damage particularly if exposed to high compressive or tensile stresses.
Ordinarily, in the construction of poured wall foundations, large and high wooden forms are constructed and secured properly in order to guarantee they are able to sustain the quantity of pressure that they will be put through in the concrete pour. In one continuous pour, concrete will be poured in the foundation forms to make sure that there no weaknesses. Poured concrete foundations usually are strengthened by making use of reinforcing steel.
For vertical reinforcement, steel bars will have been strategically installed into the footing before the concrete pour has been done. The rods used may be typically 1 1 / 2 inches across and they are usually directly coupled to the poured concrete footer the foundation rests on. However, horizontal reinforcement mandates that the steel bars be horizontally put in the upper and lower areas of the poured foundation walls. The reinforcing steel contains a high tensile strength of around 40,000 lbs per square in. This horizontal steel helps prevent the occurance of vertical cracks when the foundation heaves or drops.