Home addition questions, answered.

In many cases, yes. A room addition depends on lot size, setbacks, zoning, foundation, structure, utilities, roof design and local building codes.

Cost depends on square footage, foundation, framing, roofing, insulation, windows, siding, electrical, plumbing, HVAC and interior finishes. Bathrooms, kitchens and second-story additions usually cost more than simple living areas.

Yes. Most home additions require plans, permits, inspections and compliance with zoning and building codes.

An addition can take several months because it may include design, engineering, permits, foundation, framing, roofing, mechanical systems, inspections and finish work.

Possibly. The existing foundation and structure must be evaluated to determine whether they can support another story. Engineering, permits and major construction planning are usually required.

Building out may be simpler when enough lot area is available. Building up can preserve yard space but may require more structural work. The best option depends on the property, budget, zoning and design goals.