Building a home extension - How difficult?

Question

I am considering buying a house in Jersey City. It has a big lot size but the built space is really small. What is the process for getting an extension built? Obviously, the construction cost will depend on the space I want to build and how modern I want it to be. What would be the permit approval related cost be approximately?

Jim Adrian · Answer

You will need plans for permit for sure.  Call the local building dept and ask them. This may be online as well.  Because its a house you won't need an architects deal in the drawing but its money well spent to get an architect. They are abke to space plan better than a contractor. I would budget $75/100 per sq ft. Arch fees around 8% of construction cost.

Kevin K. · Answer

Hard to give you a sense of cost, but I can tell you what's involved.  You'll need an architect to prepare plans that would be submitted, reviewed and eventually approved by the building department as part of issuing the permit.  The extension would have to be up to current building code (i.e. electrical, smoke det, etc.)...architect can tell you more.  Depending on the scope/size of the project, the plans could cost a few thousand dollars (really depends on scope though).  Check the zoning to make sure the addition would even be allowed under zoning rules.  An architect can tell you but usually you can read the zoning laws yourself or ask the building department.

From a construction perspective, you're talking about the same steps that would be involved in new construction...footings/foundation, masonry, framing, roofing, siding/exterior, electrical, plumbing (if needed), etc.  It involves coordinating multiple construction trades which is no easy task.  If your GC has done ground up construction, then he should be able to handle it.