Home Inspection - Exterior Walls

Exterior walls provide the main structure of the home. It is imperative that the exterior walls are structurally sound and are properly sealed to provide the intended protection from the outside elements.

The exterior wall is comprised of several different parts. In this diagram you can see the finished grade where a house will be built. The cement footings are poured and the foundation and slab are laid in order to support the weight of the home. Next, a wooden frame is built and drywall, insulation, and a vapor barrier generally makeup the inside portion of the wall. What is seen from the outside is the exterior wall's veneer, which can be made of stucco, brick, siding, or some other material. Note there is a difference between the foundation of the house and the exterior wall. Exterior Insulation and Finishing Systems or EIFS, are generally face-sealed wall systems. EIFS systems that are faced sealed, meaning they contain no drainage space between the exterior veneer and vapor barrier maybe inherently flawed, making them unfit for use in all but very dry regions of the country.

Modern home science has advocated a new stacking order for exterior wall materials. This was implemented because the old way was not allowing the exterior walls to dry out properly causing mold to grow inside the walls. This new technique utilizes the same wooden frame. Next, un-faced insulation bats are sandwiched between drywall and plywood. Then two layers of 1-inch extruded polystyrene, or XPS foam, are installed with their seams staggered. A vapor barrier is installed and wooden spacing strips are mounted creating a drainage channel and allowing proper ventilation. Lastly the exterior wall's veneer is built. This technique is relatively new and may take a few years to be implemented market wide.

When inspecting a home, it is important to look around the entire exterior of the house. Check the general condition of the outside walls to see that they are structurally sound with no visible damage. The walls should be clean and free of plants and other items, which can promote deterioration. It is highly discouraged to ever allow vines or other plants to grow up along the side of the house. Plants grow into the walls and began to force there way into the cracks, opening up the surfaces of the wall. This can damage mortar joints and loosen shingles, not to mention the dampness associated with vines can promote rot and other problems. Vines themselves can hide wall damage while providing access for insect infestation, which can promote structural damage and health hazards. Deteriorating items placed up along the side of the house such as stacked firewood can encourage insects to come into contact with the exterior walls, so never place decomposable material in contact with the exterior walls of the home. This is a proper way to store firewood against the exterior wall of a house.

Around the outside of the house there should not be any exterior wood damage from dry rot or insect infestation. Look for areas where the wood seems to be withered or dried out. Damaged wood will often look like a dried piece of fruit, shriveled up or not quite firm, and square. Lightly stick a sharp object into any questionable wood and if it penetrates then the wood is damaged. The wooden surfaces outside the house should be well painted or covered with a weather sealer to prevent deterioration from exposure to the elements. As you can see here, this paint has blistered on this wooden siding and needs to be repaired. Fascia and soffit boards should also not be warped or cracked.