We build garages both detached as accessory structures on our properties as well as build attached garages as additions to our homes. Garages have a variety of uses. Obviously, we build garages to house vehicles, lawn equipment, yard and house material. We build garages to have “hang out time” with the friends and don’t want company. We use garages and workshops for a myriad of hobbies. We use garages as additional office space, or for dark rooms.

What we are going to put in the new garage, barn or addition largely dictates how to design an appropriate concrete or block foundation. State and Federal Building Codes have prescribed requirements for live load distribution. For obvious reasons, the live load of a home is much more severe than a standard 3 Car garage.

In homes, each room has a specific purpose which dictates different amounts of live load. A kitchen, for example, has a very high live load per square inch requirement due to the weight of the cabinets and appliances. A storage closet has almost no weight on the floor at all. That being said, live load is a per square foot requirement for any type of floor system, whether concrete or wooden floor joists without discrimination.

When using an accessory building as a garage, the weight of an automobile demands the use of concrete as a foundation. A residential wooden floor system cannot support the weight of an automobile. The tensile strength in concrete is higher than other materials and more suitable for automobiles. Elevated garage floors must be capable of supporting a 2,000.00 pound load applied over a 20 square-inch area, which equates to 50lbs/square foot.

A foundation that is built, perhaps for an area of the new garage and addition that is only going to be used for office space or a non-equipment storage area wouldn’t need the same tensile strength that an automobile garage would. The foundation requirement for this type of use is only 40lbs/square foot. In residential construction there three different pounds-per-square-inch mixtures used.

Therefore, if you want to build an accessory building, garage or addition, an expert building contractor will speak to you at length to determine the appropriate pound/sf requirement. One thing to remember when planning your next construction project is to plan for more weight required rather than less. If your workshop would need to house your son’s car unexpectedly one day, the foundation may not be able to properly withstand the weight of that vehicle.

Call H.W. Enterprises, Inc. who will help you plan appropriately and build accordingly. H.W. Enterprises has been building garages, barns, additions and shell homes for over 59 years. Visit our website at: http://www.hwenterprisesinc.com or call 757-595-4562 office or 757-696-1927.

The footing for a garage or addition is a fundamental and very important part of new construction. Footings have specific prescribed requirements by the State and Federal governments. In Virginia, the minimum footing size is 16” x 20”. This allows for a 4” reveal on either side of the wooden wall or block. Any veneer, such as brick, can only bear its own weight. You cannot build any new construction wall of a garage on a veneer. Therefore, an 8” block, centered, allows for 4” projection both inside the foundation and outside the foundation. If double block or concrete stem walls are used, the footing depth and width is adjusted to carry the weight of the additional foundation material being used.

So, what does all of this mean? Look at the pictures below.

Insulation is a critical component to building. There are so many considerations as to HOW a garage, accessory structure or attached garage is properly built. Despite the best of trade work, no line is perfectly straight. No hole perfectly bored. There is an industry standard that the State and Federal government prescribe for all Contractors.

Having several interacting components such as HVAC, Electrical, Mechanical and Plumbing work all running together in the walls and ceilings of garages and additions require fire-hazard and insulation evaluation. Wires have to have a grounding point and need special insulation to properly conduct electricity. Electrical services require holes and notches in and around lumber – studs and trusses. A grounding rod is used in monopour foundations, or rebar in the footing can be tied together with copper wire mesh to prevent imploding. HVAC work requires areas to run ductwork and plumbing requires ample space through the slab and floor joist systems. All of these holes and areas have to be insulated to protect them from decay as well as the escape and infiltration of air.

When attaching a new garage to your home, the foundation area and adjoining walls have to be insulated. The footing and slab must be insulated both vertically and horizontally in many cases. The International Residential Building Code requires the following:

Vertical wall insulation of frost protected shallow foundations that adjoin (point of attachment) a slab-on-ground foundation that does not have a monthly mean temperatures maintained at a minimum 64 degrees are required to have insulation. Vertical wall insulation shall extend between the frost protected shallow foundation and the adjoining slab foundation. If you are adding a new garage to an existing heated structure, horizontal and vertical insulation is not required between the frost-protected shallow foundation. An exception to this is if the new attached garage forms an inside corner, only horizontal insulation is required in that instance.

All horizontal insulation placed less than 12 inches below the ground surface or that portion of horizontal insulation that extends more than 24 inches from the foundation edge can be insulated by the concrete foundation. Standard garage foundations have footings that are 16”x20” and a standard concrete slab is 4” thick in Virginia. Therefore, insulation is not required in these instances.

Each property and garage project is unique in some way. H.W. Enterprises, Inc. has been building garages, barns and additions for over 59 years and no two building plans were the same. Call a professional who knows State and Federal building codes. Call H.W. Enterprises, Inc. in Newport News, VA at 757-595-4562 or 757-696-1927.