Excavation For Construction

Phase 1: Excavation and Plot Lines:

When preparing for the excavation for construction, be sure to check with utility companies that service the area to see if the digging will interrupt or disrupt any buried services. Accidentally cutting into power lines, gas lines, telephone lines, etc can be very expensive and you can even cause severe injury. Moreover, when deciding where you will place your house on the land you need to check with the municipality for minimum setback and side yard requirements.

Clear the site so you can be certain that the perimeter of the house is visible and mark the perimeter by following the corners of the lot. These corners will be the reference point for your house lines and excavation work. When we wanted to start setting the measurements and lines of the house we did two main things. 1) We used something called the triangulation method to measure for squareness of building corners. 2) We marked the excavation area.


The corners of our house were marked with small wooden spikes and additional marks were made in the event that the spikes were lost during excavation (our team just spray painted the ground with fluorescent paint). Something to keep in mind is that typically, excavations are done 600 to 700 mm wider than the corners of the house (24-48 inches) so that there is extra space for installing the formwork, applying dampproofing, installing the exterior insulation, and placing the drain tile. Here is a great money-saving tip. All the topsoil that is on the area marked for excavation can be stripped, stored and reused at a later date. All other soil that is dug up through the excavation is usually taken away.
 

Healthy Housing Tip: When giving thought as to how you can minimize environmental impacts and also how you can save energy, give consideration to environmental elements such as solar access, wind effects, and water runoff when deciding where you will place the house on the lot. Here are some great tips: - High performance windows give good natural lighting and can save energy while providing a beautiful view. - Orient the house in such a way that you can use wind as natural ventilation. - Try to follow natural water runoff patterns. - Collect rainwater and use it to water gardens and to wash exterior items. - Passive solar heating can be taken advantage of when you orient the house 14 degrees west of south and 20 degrees east of south.

 

Now comes the fun part – starting the excavation with the heavy duty equipment! Most likely the builders will use either a bulldozer or power shovel. How deep you go for the excavation and the exact elevation of the foundation will depend on the elevation of the street, sewer and water services, and the shape of the lot and the level of the finished grade around the house. Also, in terms of your house itself, the amount of headroom you want in your basement and the elevation of the floor above the grade also impacts how deep the excavation will be.

Headroom for the basement can be anywhere between 6 ft 5 in (1.95 m) to 7 in (2 m), but if it will used as a living space then the minimum headroom should be 7 ft 7 in (2.3 m). Also make sure that the excavation does not impact the foundations of surrounding homes. If the excavation is going to be done in the winter, make sure to protect it because building on frozen soil can create many expensive and difficult problems.