Additions: The national average cost for an addition is $190 per square foot. Homeowners who opt to add square footage to their existing home typically do so because they love their neighborhood, neighbors, school district, proximity to work, etc.

• Bathroom Addition (Mid-range): National average cost $22,977 / $478 per sq ft.
  Add a full 6-by-8-foot bath located near bedrooms over a crawl space with poured concrete walls. Include cultured-marble vanity top with molded sink; standard chrome faucets; 30-by-60-inch fiberglass tub/ shower with ceramic tile surround; single-lever temperature and pressure-balanced faucet; white low-profile toilet; general and spot lighting; mirrored medicine cabinet; linen storage closet or cabinet; vinyl wallpaper; and ceramic tile floor.

• Deck (Mid-range): National average cost $11,294 / $35.29 per sq ft.
  Add a 16-by-20-foot deck using pressure-treated SYP joists supported by 4x4 posts set into concrete footings. Install composite deck material in a simple linear pattern. Include a built-in bench and planter of the same decking material. Include stairs, assuming three steps to grade. Provide a complete railing system using either a matching system made of the same composite as the decking material or a compatible vinyl system.

• Family Room (Mid-range): National average cost $54,733 / $136.93 per sq ft.
  In a style and location appropriate to the existing house, add a 16-by-25-foot room on a crawl space foundation with vinyl siding and fiberglass shingle roof. Include drywall interior with batt insulation, pre-finished hardwood floor, and 180 square feet of glazing including windows, atrium-style exterior doors, and two operable skylights. Tie into existing HVAC. Add electrical system to code, including 12 recessed ceiling lights.

• Garage: The national average cost for building a new garage is $50 to $65 per square foot depending on features. A typical double car garage (20-by-22, 440 sq. ft) would cost between $22,000 and $28,600.

• Master Suite Addition (Mid-range): National average cost $73,370 / $191.07 per square foot.
  On a house with two or three bedrooms, add a 24-by-16-foot master bedroom suite over a crawl space. Include walk-in closet/dressing area, whirlpool tub in ceramic tile platform, separate 3-by-4-foot ceramic tile shower, and double-bowl vanity with solid surface countertop. Bedroom floor is carpet; bath floor is ceramic tile. Painted walls, ceiling, and trim. General and spot lighting, exhaust fan.

• Two-Story Addition (Mid-range): National average cost $80,133 / $104.34 per square foot.
  Add a first-floor family room and a second-floor bedroom with full bath in a 24-by-16-foot two-story wing over a crawl space. Add new HVAC system to handle addition.
  Family room: Include a prefabricated gas fireplace; 11 3-by-5-foot double-hung insulated clad-wood windows; an atrium-style exterior door; carpeted floors; painted drywall on walls and ceiling; and painted trim.
  Bathroom: 5 by 8 feet. Include a one-piece fiberglass tub/shower unit; standard white toilet; wood vanity with solid-surface countertop; resilient vinyl flooring; and mirrored medicine cabinet with built-in light strip; papered walls; and painted trim; exhaust fan.
  Bedroom: Include walk-in closet/dressing area; carpet; painted walls, ceiling, and trim; general and spot lighting. 

Remodels:

• Basement Remodel (Mid-range): National average cost $51,051 / $65.11 per sq ft.
  Finish the lower level of a house to create a 20-by-30-foot entertaining area with wet bar, a 5-by-8-foot full bath, and a 12-by-12-foot auxiliary room. Walls and ceilings are painted drywall throughout; exterior walls are insulated; painted trim throughout. Include five six-panel primed hardboard doors.
  Main room: Include 15 recessed ceiling light fixtures and 3 surface-mounted light fixtures, and a snap-together laminate flooring system.
  Bathroom: Include standard white toilet, vanity with cultured marble top, resilient vinyl flooring, two-piece fiberglass shower unit, a light/fan combination, vanity light fixture, and recessed medicine cabinet.
  Bar area: Include 10 linear feet of raised-panel oak cabinets with laminate countertops, stainless steel bar sink, single-lever bar faucet, under-counter refrigerator, and vinyl floor tile.

• Bathroom Remodel (Mid-range): National average cost $10,499 / $299.98 per sq ft.
  Update an existing 5-by-7-foot bathroom that is at least 25 years old. Replace all fixtures to include 30-by-60-inch porcelain-on-steel tub with 4-by-4 ceramic tile surround; new single-lever temperature and pressure-balanced shower control; standard white toilet; solid-surface vanity counter with integral double sink; recessed medicine cabinet with light; ceramic tile floor; vinyl wallpaper.

• Minor Kitchen Remodel (Mid-range): National average cost $14,913 / $74.57 per sq ft.
  In a functional but dated 200-square-foot kitchen with 30 linear feet of cabinetry and countertops, leave cabinet boxes in place but replace fronts with new raised-panel wood doors and drawers. Replace wall oven/stove with new energy-efficient models. Replace laminate countertops; install mid-priced sink and faucet. Repaint trim, add wall covering, and remove and replace resilient flooring.

• Major Kitchen Remodel (Mid-range): National average cost $43,862 / $219.31 per sq ft.
  Update an outmoded 200-square-foot kitchen with design and installation of a functional layout of 30 linear feet of semi-custom grade wood cabinets, including a 3-by-5-foot island; laminate countertops; and standard double-tub stainless-steel sink with standard single-lever faucet. Include energy-efficient wall oven, cooktop, ventilation system, built-in microwave, dishwasher, garbage disposal, and custom lighting. Add new resilient flooring. Finish with painted walls, trim, and ceiling
  *Designers and Architects will often advise to plan on spending approximately 15% of your home’s current value towards a kitchen remodel. For example, you might expect to budget approximately $45,000 for a kitchen renovation in a home with a current market value of $300,000.