How to Lay a House Foundation
All houses need a proper base for a strong structure, and the most popular type of house foundation is a concrete slab. They are the easiest kind for any DIYer to make. Follow these steps and you can lay your own basic concrete foundation with ease.
Step 1 - Prepare the Ground
After you have determined the desired thickness of your foundation, you need to get the ground ready to install it. Clear the area of any large stones, branches, or other disruptive objects, and then excavate a space that is twice the depth of what your final foundation will be. Using a shovel in this case can be back-breaking labor, but in the event that you can't rent bigger digging equipment, it will suffice.
Next, level and compact the soil; this can be done with a rented compactor. Keep checking your surface as you go over it with the level and add soil back if needed. Follow up with a loose, even layer of sand or gravel over the area. This will prevent moisture from seeping up through the ground while you lay your concrete slab. Then, lay some polyethylene as a waterproof membrane over the layer of sand or gravel.
Step 2 - Build a Frame
Construct a wood form out of 2x4 lumber that encircles the excavated site, according to your specific structure's necessary dimensions. Make sure you have screed rails on the opposite and exterior sides of this perimeter. Then, lay a straightedge (a 2x4 or other long and flat material) across the expanse of your frame, ultimately resting on the screed rails. Support these rails with metal stakes so they stay firmly in place after the concrete is poured. Place them so that the bottom of the straightedge sits at the level where the top of your slab will be.
Step 3 - Mix and Pour the Concrete
Now you are now ready to start working with the actual concrete. Take a wheelbarrow or bucket and fill it with the proper mixture of concrete and water. Keep a close eye on your consistency and adjust it as needed. Begin pouring it into your foundation frame. As the concrete fills the space, slide your 2x4 straight edge across the screed rails to level the surface while it's still wet. Once all the excess concrete has been removed and your concrete house foundation is leveled, remove the screed rails and straightedge.
Step 4 - Finishing Up
Use hand trowels or power trowels to remove flaws in the smooth texture of the concrete. This must be done while the concrete is still wet and malleable, so get to it as soon as you can. Once you have completed this step, leave the foundation to dry and cure. Different types of concrete require different amounts of time to cure, so follow any instructions given on your mix for the best results. Also, concrete will cure better if the surface is kept moist while it sets.