The sequence of events for the foundation work follows.
Footing subs dig the footings,
Exterminator treats the soil in and around foundation of custom home.
Inspection of footings before pouring,
Footings are poured.
Foundation walls are laid or poured (basement construction).
Plumber and HVAC subs lay water, sewer and gas pipes before
slab floor is poured (slab only construction).
Slab is inspected.
Slab is poured by concrete finishers.
Basement wall is waterproofed.
Basement wall drainage system is installed.
Trees to be save should be tagged and septic tank or driveways should also be cleared. If a driveway curb is to be cut mark it and do so now. It will make access to the site much easier.
The custom home building site can now be cleared of large trees by use of a grader.
Have the grader clear the topsoil to a safe spot for use after construction.
Mark the foundation area with stakes or lime after checking for proper building dimensions.
Before digging begins the first thing to do at this point is locate all underground utilities by using a service or utility company.
Have gas, water, electrical and phone lines marked on the site with flags just prior to beginning. Determine and clearly mark exactly where the custom house is going to be situated, keeping in mind all allowances, setbacks, and utility or highway easements. Mark all corners with stakes.
There are different types of foundation walls in Custom Home Building.
Concrete block is less expensive than poured walls. The block walls must be leveled by hand and the block coated with two layers of portland cement below grade level.
Poured walls are more expensive but are stronger and more impervious to water. If you are having brick exterior you must tell the from sub so he can provide for a brick ledge in the forms. This is what the brick wall rests on.
Foundation floors are poured after the footings and walls have been cured. They are usually four inches thick and should be finished as close to level as possible with a slope toward drains.
Concrete work must be done when the weather is not extreme. If it is too cold, too hot or too wet there are measures that should be taken to ensure a good job.
Schedule work when dry weather is expected but have heavy plastic available in case the forecast changes.
Prior to the day cover the area with plastic or tarps to keep excess moisture off the area.
In hot weather you must keep the concrete form drying too quickly as this increases the chance of cracking and reduces strength. cool the aggregate with water before mixing. Use cold water for mixing, Keep materials shaded.
Work at night or very early in the day. Once poured cover the are with wet straw or tarps.
In cold weather heat the aggregate and water and mix before adding the cement. Heat the sub grade, if frozen so it will not freeze during curing.
High-early-strength concrete can be used to reduce the time needed for protection from freezing. If necessary use tarps and heated enclosures during the curing process.
For a poured or concrete block foundation the digging can now be done. It should be 3 feet larger all around than necessary to allow access for forming.
It is extremely important at this stage that measurements be done to keep the foundation level to avoid problems later on with sewer lines being too low. This would create water problems in your basement. Cut too high and the house will require more steps at the front porch and a steeper driveway. However it is better to be too high than too low to avoid water problems in the future.
Once the foundation is in the water proofing is done on the custom home. If the foundation is a poured wall a coating of hot tar, asphalt or bituminous material is applied to the exterior wall followed by a layer of 6 mil poly applied to the tar while still tacky. Masonry blocks are coated with two layers of portland cement (a special cement that dries under water) and the joint between the footing and the wall is filled with portland cement.
If it is a slab foundation the water sewer and gas pipes would be laid after the site is cleared and footings are poured. Once that is done the slab can be poured for your custom home.