Americans usually build house walls with dimensional lumber (typically 2x4s and sometimes 2x6s). This process is simple, fast, and inexpensive, although dimensional lumber is less available and more costly in other parts of the world. The framing crew typically assembles 2×4 walls lying on the foundation, with a 2×4 base plate, two 2×4 top plates, and 2×4 studs in between, spaced 16 inches on center. Nails are better than screws, because they are cheaper, quicker, and more flexible under pressure. You can rent a nail gun, compressor, and hose, but a hammer is fun and won’t take that much longer. You’ll also get really good at it. Watch Karate Kid II if you’ve never received formal training on hammering nails, or if you appreciate cinematic masterpieces. Use two nails to attach the top and bottom plates to the studs on the end of each wall section, and one nail for the studs in the middle.
After the wall is assembled, it can be tipped up into place and attached to the foundation with concrete anchors. It will be necessary to rent a hammer drill to install the concrete anchors, and to use a bit slightly larger than the diameter of the anchors. Typically, ½”-diameter anchors are installed with a 5/8”-inch bit. A Home Depot Tool Rental (or other tool rental business) will usually be able to rent the drill out for as little as four hours, and you should be able to drill all the holes in less than 30 minutes, if the walls have already been stood up and held in place. Alternative systems for the anchoring are TapCon, Ramset, and j-bolts that are placed in the wet concrete.
After you attach the roof to the walls (described in the next post), attach OSB sheathing to the framing. A product like the Georgia-Pacific Forceshield OSB can be installed without Tyvek house wrap, simplifying the building process. For this product, it is only necessary to tape the seams between the pieces of OSB with Georgia-Pacific’s panel system tape.
After the roof, windows and doors are installed, the walls can be finished by installing trim and siding. 8.25-inch Hardie lap siding is inexpensive, quick to install, and looks great. The basic steps to install (like most building trades) are measure, cut, and fasten. You can make straight cuts with a utility knife, by scoring the front of the siding with a straight edge, supporting the back of the scored line, and snapping the excess length off. An angle grinder can be used for more complicated cuts, and to cut thicker trim pieces. However, a circular saw equipped with a dust collection system is best, because the dust from cutting fiber cement siding contains silica fiber which is not good to breathe in.
To install the siding, focus on one wall at a time. First install Hardie 1×4 trim around all doors and windows and on the corners of the house. The trim should be installed with 2” finish nails (using a nail gun will speed the process up). After the trim is installed, the first course of lap siding can be installed on top of a 1.25”-wide strip of siding material to form the base. This base allows the first course to sit at the same angle as all the higher courses of siding. Predrill the base strip before nailing to keep it from cracking. Use hot-dip galvanized nails.
After installing the base strip, install the first course of siding. Leave a 1/8” gap between the siding and trim in all areas. This will allow for minor movement and thermal expansion/contraction. You can caulk it before painting to make it waterproof. Place a small, rectangular piece of Tyvek house wrap (approximately 6” wide x 8” tall) beneath each butt joint between two pieces of siding. This Tyvek piece should lay over the piece of siding in the course beneath (or the base strip for the first course). It should be nailed to the wall at the top. It will help the wall to shed any water that penetrates the butt joint. Continue attaching siding pieces to finish the first course, and cut the last piece to fit, with the cut on the side facing the corner trim.
Use Gecko Guage siding clamps to hang the second and all subsequent courses at exactly the right overlap (7 inches). Use the leftover piece from the cut for the last piece of the first course to start the second course, keeping in mind that all butt joints between courses should be staggered horizontally by at least 6 inches. Continue working up the wall, ensuring that butt joints are not placed directly beneath window corners. It may be necessary to make “L” shaped cuts around window or door trim in some areas.
The top of the top piece of siding should be at or above the level of the soffit board that you will eventually install to enclose the rafter tails of the roof (typically 8’ or more above the bottom of the siding). After installing the siding, the soffit boards and fascia trim can be installed using the same methods as for the siding. If working alone, it may be necessary to use screws with a drive guide bit to attach the soffit while holding it with the other hand.
Caulk and paint the siding as soon as possible. It is not necessary to caulk the butt joints between siding pieces. The siding can be spray painted but painting with a brush and roller doesn’t take that long, uses less paint, and does not require special equipment.