David Chen
Licensed Professional Engineer
Third-generation builder. My grandfather built homes in San Francisco after the 1906 earthquake, my father ran a construction company for 40 years, and I grew up calculating concrete volumes at the dinner table. After 15 years as a Professional Engineer (PE) and building my own 2,400 sq ft home from foundation to roof, I know exactly where contractors cut corners and how homeowners can save thousands. Based in Portland, OR, where my garage workshop is bigger than most living rooms.
Articles by David Chen (5)
How to Build a Deck: Complete Materials & Cost Calculator Guide
How to Build a Deck: Complete Materials & Cost Calculator Guide Building a deck costs between $15 and $75 per square foot for materials, depending on whether you choose pressure-treated lumber, composite, or cedar. A typical 16x20 deck requires 50-60 deck boards, 20-25 joists, 8-12 posts, and roughly 15 pounds of structural screws and hardware. Getting the material quantities right before you order saves hundreds of dollars in waste and emergency trips to the lumber yard. Last year I built a 16x24 composite deck for a client in suburban Maryland. The material bill came to $8,200 -- and that was after negotiating a bulk discount on the composite boards. I ordered 15% extra decking and used every single piece, because cuts around the stair landing and the angled corner ate through boards faster than the calculator predicted. That project reinforced what I tell every homeowner: always round up, never down....
Drywall Calculator Guide: Sheets, Mud, Tape & Cost for Any Room
Drywall Calculator Guide: Sheets, Mud, Tape & Cost for Any Room A standard 12x12 room needs approximately 18 sheets of 4x8 drywall for walls and ceiling. Each 4x8 sheet covers 32 square feet, and a typical room with 8-foot ceilings requires about 576 square feet of wall area plus 144 square feet of ceiling. Factor in 10-15% waste for cuts around doors, windows, and outlets, and you get a reliable material estimate before heading to the lumberyard. When I drywalled my first basement two years ago -- 850 square feet of open space with a drop ceiling grid -- I ordered 22 sheets of 4x8 and thought I had plenty. I was wrong about the joint compound. I ran through 3 gallons in two days and had to make an emergency run for 2 more, which set me back half a day and $45. That project taught me that accurate...
Fence Cost Calculator: Posts, Panels & Materials for Any Yard
Fence Cost Calculator: Posts, Panels & Materials for Any Yard The average fence costs $15-$45 per linear foot installed, depending on material. A 150-foot wood privacy fence typically costs $3,000-$5,500 for materials alone, while vinyl runs $3,750-$7,500. Chain link is the most affordable at $1,050-$3,000, and aluminum ornamental fencing ranges from $3,750-$6,750. Total installed cost adds $5-$20 per linear foot for labor. When I installed a 175-foot cedar privacy fence around my backyard in Portland two years ago, the project came to $3,200 in materials -- 23 posts, 22 panels, and two gates. The lesson I wish I had learned before digging the first post hole: I was 14 inches over my property line on the south side. A $400 survey would have saved me from pulling up three posts and resetting them, plus an awkward conversation with my neighbor. Always get a survey before you set a single post....
Insulation R-Value Guide: How Much Insulation Do I Need?
Insulation R-Value Guide: How Much Insulation Do I Need? R-value measures insulation's resistance to heat flow -- the higher the number, the better the insulation. Most homes need R-38 to R-60 in the attic and R-13 to R-21 in walls, depending on your climate zone. The U.S. Department of Energy divides the country into seven climate zones, each with specific R-value recommendations that determine how much insulation your walls, attic, and floors require. When I upgraded the attic insulation in my Portland home from R-19 to R-49 two winters ago, the project cost $1,800 in materials and a long weekend of work. My gas bill dropped by $340 the following year -- a payback period under six years, and the house stayed noticeably warmer during our typical 35-degree January nights. That project convinced me that upgrading insulation delivers the best return per dollar of any energy improvement a homeowner can...
How Much Roofing Material Do I Need? Shingles, Bundles & Cost Guide
How Much Roofing Material Do I Need? Shingles, Bundles & Cost Guide A roofing "square" covers 100 square feet of roof area. Most asphalt shingle roofs require 3 bundles per square, so a 2,000-square-foot roof needs roughly 60 bundles (20 squares). You must also factor in roof pitch, waste from hip and valley cuts, and starter and ridge cap shingles to arrive at an accurate material order. When I re-roofed my 1,800-square-foot workshop two years ago, I measured 18 squares of flat area but ordered materials for 20 squares because the steep 8/12 pitch added nearly 12% to the actual surface area. Even with that cushion, the hip-and-valley waste from the L-shaped footprint consumed an extra 2 squares worth of shingles -- I burned through 66 bundles total and spent $4,150 on architectural shingles, underlayment, and ridge vent. That project hammered home how much roof geometry matters beyond a simple...