If you fancy taking on the project yourself, there are steps that you can follow in order to complete the job like a pro. Here is an overview of those key steps for Building Foundation for a Room Extension.
Step 1: Survey the Selected Site
Start by surveying the area which you have earmarked for the home extension. Find out if there are any buried utility lines underneath your chosen site. A call to the utility companies can also yield the desired information. Have any utilities found diverted before work on the foundation begins.
Step 2: Prepare the Ground
The next step you need to perform is to get the site ready for the work ahead. In this step, remove any large stones or other debris that may make it hard for you to excavate the site. You can now use a shovel or any earthmoving equipment accessible to you to excavate a hole which is two times as deep as you want the foundation to be. The right depth of the foundation can be known by visiting the building authorities in your area for advice. Build a mesh fence around the site so that you avert any accidents which would have occurred in case someone fell into the excavated hole when visibility is poor.
Step 3: Create the Base Layer
Level and compact the soil in the hole. Pour some gravel or sand over the compacted soil so that water is prevented from seeping upwards as you pour the concrete in the foundation. Remember to install some form of waterproofing (a waterproofing membrane, for example) on the gravel or sand layer.
Step 4: Build the Frame
In this step, you will build the formwork for the concrete pour. Drive evenly spaced stakes into the ground around the area you have marked for the foundation for that home extension. Nail 2×4 lumber against the stakes so that a gap for the desired wall thickness is left between the forms. This applies when you will include a basement in that extension. Otherwise, the forms can just demarcate the boundaries of the foundation. Cross check and confirm that the top of the lumber doesn’t exceed the desired height of the foundation.
Step 5: Pour the Concrete
Get the appropriate concrete mix from a concrete contractor near you. Alternatively, you can buy the different products from a hardware store and mix your own concrete in case the foundation isn’t covering a large area. Make sure that all the concrete you use is of the required consistency. Keep adding water in case you notice that the consistency is changing. Pass a straight edge over the top of the concrete in order to prevent it from exceeding the desired height.
Step 6: Finish Up
Use a power or hand trowel to smooth out any imperfections on the surface of the foundation. Do this when the poured concrete is still malleable. When satisfied, leave the foundation to dry. The drying time will depend on the concrete mix used and the weather at the time. Keep the surface of the concrete moist so that the curing process isn’t too fast.
You can proceed with the construction of the home extension once the foundation has cured to the required level.