New House Construction Today
A finished newly built house can be pleasing to look at, perhaps impressive, perhaps not, But what it has taken in turning a piece of land into a modern home, is a series of substantial levels of building.
First move, are the plans and surveys. These will determine what each specialist sector of house building will do in what order.
First the site will have to be cleared. This may be as simple as a bulldozer scraping vegetation away, or if the ground slopes, earth may have to dug and removed, using machines and trucks.
Before the foundations are begun, it maybe that the ground may not appear to be easy to work on and a structural engineer may be employed to survey the area.
Trial holes may dug around the site and subsequent advice on the best way of placing the foundations.
By employing a structural engineer, the responsibility of the foundation of the whole building then lies with them and can lead to over cautious recommendations, often using pilings.
If the soil has a poor or loose composition foundation options can be assessed and budgeted for. It may also bring to light any hidden problems like old well shafts, or uncharted pipe work.
This may be a more expensive start than anticipated, but the costs of modern piling have come down as new technology has entered the field.
The underground workings are the most variable expense of the construction, as what lies below the surface comes to light.
Provided the soil is reasonably solid and supportive the most usual type of foundation mean that trenches will be dug to the plan of all the load bearing walls.
These are usually dug out with a backhoe or mini-digger, depending on access and manoeuvring space.
These will be a minimum of one metre deep. At this point the local building inspector has to assess the state of the trench bottom to ensure the base soil is stable.
Ready mix concrete is then poured in as a shallow layer, and allowed to harden, or cure. On this base brick or blockwork is built up to the surface level, or damp course. These are strip foundations.
Alternatively the trench may be filled entirely with concrete almost to ground level, where the damp proof course is used and the floor fixed on. This is trenchfill foundation.
If the trenches have to be dug deeper to achieve stability, of the costs will go up. The maximum trench depth is at around 2.5 metres, after which it becomes both unsafe and uneconomical to proceed and piling is the next option.