| | Establishing ‘relative grade’ is extremely important in the site work phase of new construction. - When ‘placing’ a structure on any lot the grade from the top of grade to the bottom of the ‘cut’ is critical. The cut must be figured from bottom of foundation wall, in caisson construction or bottom of footing. Wall height and the amount of foundation to be exposed above grade must be considered. The worst scenario is when the cut is made too deep. This usually will not allow for enough ‘fall’ away from the foundation to allow the surface water to run off. Great care should be taken to make sure the excavator knows and follows the established ‘sub-grade’.
- On sloped lots the grading is equally important for the same reasons, but there are new factors to consider. First, is where the ‘walk-out’ or ‘garden-level’ grade is going to intersect the existing slope of the lot. The frost wall, which is below the grade at the lower slope must be adjusted to a depth where it can have the minimum of 3’ below grade without having to add too much fill. Too much fill creates and even steeper grade ‘below’ the structure.
 | | Notice in this example that in order to keep the frost wall at 3’ below grade the wall above grade has to be quite tall. The foundation steps are often set on site, so the adjacent grade can be examined to determine the best location for them. |
- Proper relative grade is the first step towards a properly constructed foundation. Good bench marks set by a surveyor and/or an experienced construction field supervisor are recommended for this important phase of construction.
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2x10 Door and Window Headers: Remember to provide some R-19 batt insulation at the framing stage so the framers can ‘stuff’ the header voids prior to installation. Use 24” o.c. material so they can be cut in half and each piece used for two headers. |  Excavation on Steep Terrain:
- Plan for debris falling from property: Install wire mesh fencing over short fence posts with the wire braced to metal stakes with tie wire. Add silt fence and or straw bales in front to keep rocks and silt from ‘leaving the property’
- Remember! Equipment will have to drive all the way around the perimeter of the foundation: plan a road way during the design phase to make sure there is room between the foundation and property lines or obstacles (such as trees, boulders, etc.) Protect valuable land assets from equipment with planning and protective boundaries.
- Leave the flat area for scaffolding and ladder setup during the construction process. Grade up to the foundation to achieve the desired slope away from the structure during the final grade phase.
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