18 Feb Cost-Effective Piling Solutions for Small-Scale Projects
Piling is a construction technique that’s been used for centuries, providing support in soil conditions where shallow foundations are unsuitable. Piles work by transferring the load of the structure down to either a firmer level of subsoil or to the bedrock.
Traditionally, piling has tended to be used for major projects, and it’s still crucial for structures like bridges or oil rigs. Advances in piling techniques, however, have in recent decades begun to be used for domestic buildings or small industrial sites. So what are the most cost-effective piling solutions for small-scale projects?
Mini-Piling
The key development in creating piling solutions for small-scale projects was the introduction of mini-piling. This is especially versatile and economical for sites with limited access, or else locations where large machinery would be disruptive.
Mini-piles are small-diameter piles, typically of between 105mm and 450mm in diameter, that can be either driven or bored into the ground. They can be used to underpin a building, either to correct subsidence or to cope with an increased load, or else to add on small structures, such as extensions or outbuildings.
Mini-piles involve less noise and vibrations, and they can adapt to many different soil types, from clay to sand, as well as involve less cost for equipment. They come in two main varieties, depending on how they’re inserted into the ground — driven and bored.
Driven Piles
Driven piles are precast concrete or steel piles that are hammered into the ground. This reduces the costs for both excavation and disposal of the spoil, and they can begin bearing loads immediately. They’re especially efficient for use on soft ground.
Two techniques are used for driving piles:
- A compressed-air hammer action at the top of the pile. These machines are extremely convenient for restricted areas where the load-bearing is light. They can also be used for extensions in built-up areas since the vibrations are minimal.
- Bottom-driven piles, where all the energy is delivered to the pile toe. As an extremely energy-efficient system, this type of pile can be driven with relatively small machines, cutting down on the cost of the project.
Bored Piles
Boring, which is excellent for weak soil conditions, involves drilling a hole, inserting a casing, pouring in concrete or grout and removing the casing to leave the pile in place. Although slightly less efficient than driving, the minimal noise and vibration make up for this, as well as the low cost, especially for a project involving multiple piles.
There are two main approaches to boring piles:
- A sectional augur, where sections of casing are added into the hole as it’s bored. The rigs used for this are extremely versatile, allowing them to be manoeuvred into very limited spaces. However, the sectional augur technique can only be used in certain soil conditions.
- A continuous flight augur, on the other hand, involves inserting a single casing all the way to the bottom, which can then be filled with grout while the augur is removed. This can be installed with very little noise or vibration.
Use a Piling Specialist
Mini-piling can provide an excellent, cost-effective solution for a wide variety of domestic or small industrial projects. However, it’s vital that the work meets stringent British Standards and complies with Building Regulations. This means it’s not a job for a general building firm — you need a piling specialist, to ensure the work is done to high standards.
If you’re looking for piling contractors in London, the surrounding areas or South East England, you can contact U&M to discuss your needs.