Five Foundation Wall Choices

Video survey of the different foundation wall types. (4:13)

Video survey of the different foundation wall types with Mark LaLiberte (4:13)

There are design considerations that apply to any type of foundation system you choose.  Let’s look at each of the most common foundation wall systems; masonry, conventional poured concrete, internally insulated poured-in-place concrete, pre-cast concrete, insulated concrete form systems.

Masonry is most often referred to as a block wall.  The challenges to this system are using proper techniques like core fills, bond beams, pilasters and of course, proper water management.  A masonry wall can only be as strong as it’s weakest joint.  So proper stacking, motor mix, joint striking and back filling are critical, as with all systems.  Contrary to the thinking of many builders, this system needs to carefully control hydrostatic pressures by using drainable backfills, drainage boards or drainage mats.

Poured concrete has become fairly common in most major markets of the U.S. when basements or crawlspaces are used.  The fundamentals of a properly poured concrete wall include using 3000 PSI minimum mixes, checking the slump on site for proper consistency, vibrating or pouring in shorter lifts.  As with any foundation, it is essential to use waterproofing techniques  — like spray mastics with drainage boards or mats, granular backfill with a clay cap and effective water collection and removal systems.  In most climates, poured wall foundations need to be insulated.  Rigid insulation or insulating drainage boards are recommended to be installed in the exterior of all foundation walls.

Another method of insulating your foundation is using an internally insulated pour-in-place system.  This system has been designed for use with traditional forms.  In this system, rigid sheet foam insulation is centered in the form and held in place by a connector system.  This system allows for edge to edge insulation that takes full advantage of the thermal mass effects of the concrete, creating a well insulated, below grade foundation wall system.  This system can be engineered for a wide variety of insulation requirements.  Such as partial wall and a full wall.

Pre-cast systems are factory made and transported to your site.  The use of pre-cast panels is very common in commercial construction but fairly new to residential construction.  The technique combines high-strength concrete with rigid insulation in a single panel.  These systems may also include a cavity for wiring and additional insulation.  Some have a thin, wood interior surface to attach drywall.  One type of pre-cast system consists of rigid foam insulation sandwiched between two wits of 5000 psi concrete.  This system may be readily finished by taping joints and painting the walls., no framing or drywall is necessary.

The second pre-cast system combines high-strength concrete with rigid insulation in single panels.  This system includes a cavity on the interior for wiring, plumbing and additional insulation if needed.  They may also come with metal or wood framing to attach drywall.  Each of these pre-cast systems requires engineering for proper reinforcing, the need for a crane to set the panels and the installation of an appropriate water management system.  Some pre-cast systems can reduce installation time and labor cost.

Insulated Concrete Forms (ICFs) are a modification of traditional poured-in-place concrete.  ICFs use a rigid foam insulation as the forming system for the concrete wall.  This insulation is left in place after the pour.  This system provides the strength of a concrete wall and the warmth of insulation in one process.  The ICF system is easy to use and may be easily adapted by traditional, masonry contractors.  All of these foundation systems still require the same principles in managing water, insects and hydrostatic soil pressure.[/vc_column_text][/vc_column][/vc_row][/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]