Here in the south… attics are common for finishing into livable space vs. basements in the north. Attics unfortunately do not have the return on your investment as adding an addition on the side of your home. The average cost to convert an attic vs. build an addition is about 40-60% less than an addition. Is re-sale your major concern? If so, then I would put on the addition, but if convenience is the concern, additional space for company or the children, and you don’t plan on selling anytime soon then the attic is a great investment long term.
Additions usually cost between $100.00 to $150.00+ per square foot depending on options and styles. I typically see additions costing more around the $130.00 range. I know this is more than what most home square footage cost are, but additions take longer to complete and usually need to include existing home remodeling too.
Attic renovations are common for adding additional square footage here in the south. Most homes in the $350K and above have typical walk up attics. If not, they are sometimes difficult to do and usually take space from an existing room. Typical attic renovations cost $45.00 to $70.00+ per square foot to complete. Any home that carries a 8/12 roof pitch can have a finished attic typically. Naturally a 10/12 or 12/12 roof pitch is even better. On a 12/12 roof pitch style home, and 28′ wide, you can have a finished room of 16-18′ room x length of home using 4-5′ knee walls. Typically most people think that it is a great size room for what it will cost.
This is how I would complete the room for cost and efficiency.
1) Make sure 1st that the floor is sufficient for living space. Your floor should have 3/4″ T&G plywood or 1″ of total flooring (plywood) 2) you need to have a minimum of 12″ of rafter size, fur it down to 12″ if necessary. The knee wall should be built with 2×6 materials, add opening for storage doors as needed. 3) Roof cross ties should be 2×12 for batt type insulation, or 2×8/10 for blown in insulation, check your local code for required spans of lumber. 4) Now that you have your framing complete, done to building code, consider what you want for electrical extras, as the electrical code will require so many outlet per foot and probably more than you will ever need. You may want to consider audio/theater room wiring, recess lighting too. 5) HVAC- This is a major decision, do I use my existing system?? or install a new one?? Well, for what it cost to bring the old system up to current code, damper control, and duct-work installation, it may be cheaper to add a separate system. Attics usually run warmer in the summer months, as all sides are exposed to the weather. One floor will have to be the primary floor for the system, and one the secondary..that means when one needs A/C, the other has to wait typically 3-10 minutes before it switches, but usually when that secondary is done, the other one needs it again, then back to the other one..results in an over worked unit, higher A/C bills, and short life span of the unit. I am finding that Ductless Heatpumps are the answer for most open areas. They can be purchased from 13 seer to 21 seer for under $2500.00 less installation. The last one installed by Lifestyle building & Remodeling Co. Inc. was a 16 seer, 2-ton unit. We are getting feed back that it raised the electrical cost $30.00 per month in the August heat, not bad for 800 square feet. A typically duct type system will cost $2400.00 to $3400.00 per ton, usually 2 ton is minimum. 6) Insulation is next, and the most important for long term savings. The typical code here in N.C. is R-19 in the floors, R-13 in the walls, and R-38 in the ceilings. Here in the attic, I would stay with the building code, except I would use R-19 in the walls, as the air behind the walls/storage area are typically hotter and colder then the typical exterior walls. You will need to install either plywood, netting or Tyvex behind the knee walls to contain the insulation within the wall cavities. 7) Now you are ready for your finishes and see your room completed. It is always best to hire a Licensed General Contractor to do this work, most homeowners do not know the building codes and can spend more money down the road. Attic renovations should ALWAYS have a building permit! Banks/Building code enforcement will find out when you go to sell, or you have a claim. Consequences are not worth it. Do not let someone talk you out of one.
Lifestyle Building & Remodeling Co. Inc has been finishing attics for the last 20 years here in N.C. we are very professional, know how to do the job in a timely manner without headaches to our homeowners. As you can see, we have the homeowners long term investment in mind. Call us today 919-836-0412 or email.
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