Category Habitat for Humanity International

2. Then nail on a 1×2 fence.

If you need to make a series of plumb cuts to match and align rafter tails along an eave, make a jig like the one shown here. Use a rafter square to mark the plumb-cut angle of tie roof (4-ІП-12 or 5-in-12) on a short length of 1×4 or 1×6, depending on the rafter size. Cut a parallelogram-shaped template with
identical plumb-cut angles, then nail a short 1×2 fence to the upper edge of the template. Once a chalkline has been snapped across all the rafter tails, use this template to mark the plumb cut on them so that they can be cut to length.

MITERING FASCIA BOARDS

CUTTING AND NAILING GUIDELINES FOR GUT­TER AND FASCIA BOARDS. Use long, straight stock for gutter or fascia boards. Both types must butt together over the solid backing of a rafter tail. Gutter boards can meet in a simple butt joint; fascia boards should meet with a mitered joint, as shown in the bottom illustra­tion at left.

Nail gutter and 2x fascia boards to truss or rafter ends with 16d, hot-dipped galvanized nails. Nail fascia boards with a finish hammer, being careful not to miss the nail or you’ll leave hammer tracks in the wood. I lave a partner hold the other end of the board. Hold the board down a bit on the rafter tail so that the roof sheathing just skims over it (see the illustration on the facing page). To line up

everything correctly, tack a piece of scrap wood on the top edge of a rafter and let it project downward, the way the roof sheathing will. Drive the topmost nail high enough so it will be covered by the drip edge that will be installed later.

At the bottom corner of the roof, the cave trim meets the barge rafter. If the exterior trim will be covered with cladding, as on this house, plumb-cut the barge rafter and nail it to the plumb-cut end of the gutter board.

Install the gutter board so that it runs long, just like the lookout boards, then mark the correct overhang distance on the gutter board and on the topmost lookout. Be sure to take the barge rafter’s thickness into account. Snap aline between these two marks, then cut the gutter board and lookouts in place. Now you’re ready to cut and install the barge rafter.

The procedure is similar if you’re installing fascia instead of gutter boards; however, miter the end of the fascia board to lit a mitered plumb cut on the barge rafter (see the photo onp. 131). It’s easier to make both miter cuts before nailing the boards. Miter and install the fascia first, then snap the cutoff lines on the lookouts as described previously.

Plumb-cut barge rafters

Select straight, clear stock lor the barge rafters, and start with a board that’s a little longer than you need. Make the bottom plumb cut on the ground. This is a mitered plumb cut if vou’re working with finished trim. With one or two helpers holding the hoard above, nail the barge rafter to the lookouts and to the gutter or fascia board. I like to make the top plumb cut with the board in place, judging by eye where the top of the cut should be. When you install the opposite barge rafter, mark the top plumb cut against the rafter you’ve already cut to ensure a light-lit ting joint.

STEP 7 Sheathe the Roof

Sheathing a roof is much like sheathing a floor, except that the deck is sloped, not flat, and you work at least 10 ft. off the ground. Anyone who has worked in the construction trades for more than a few years has heard stories about someone who has fallen from a roof—or has seen it happen. 1 was sheathing a roof many years ago on a cool morning with a bit of frost on the ground. The sunny side of the roof had no frost. Without thinking, I stepped onto the shady side of the roof and was immediately careening down a fairly steep pitch, heading for doom. Fortunately, I had my straight-clawed hammer in my hand. Instinctively using it like an ice ax, I stink the claw into the sheathing, stopping myself just short of the roof’s edge—a thrilling wav to

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CODE REQUIRES AN ACCESS HOLE

for the attic. This allows workers to get into the attic to install insulation and wiring. You may also want to get up there some day to check on a roof leak or just to see how the spi­ders are doing.

The standard attic access hole has a rough 2x frame that is 22/ in. wide by 31 in. long. This rectangular opening fits nicely between ceiling joists installed on 2-ft. centers. Usually, the hole is located in a closet or along a hallway. Once you select a spot for access to the attic, cut a pair of 2x$ to lit between the ceiling joists and nail them 31 in. apart. The bottom edges of the blocking should be flush with the bottom edges of the joists. Take the time to measure the hole diagonally to

make sure its square. After V*-in. dry – wall is nailed in place, you will have a 21^-in. by 30-in. access hole.

If you are using blown-in insula­tion to insulate the ceiling, build a plywood or OSB curb around the access hole in the attic (see the illus­tration at location). Make sure the curb is tall enough (at least 12 in.) to keep the insulation from falling on your head every time you open the lid to the attic. The lid can be cut from

drvwall and should be insulated with

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rigid foam board.

Instead of a simple lid for the access hole, you may want to install a pull-down stair kit. If you’re using the attic for storage and need to go up there on a regular basis, a pull-down staircase is the way to go. The stairs
are factory-made and designed to tit in the 22’A-in. space between the joists. The rough opening must be longer, however—54 in. is common. Check the manufacturer’s specifica­tions before you frame the opening.

Create attic storage. There is some usable space in most truss-roof attics. To make use of it, don’t lay sheathing directly on the joist chords of roof trusses, since trusses are not engineered for this. Instead, frame a storage platform above the joist chords, making sure that there’s room for insulation beneath the platform. You can support the platform’s joists on short (8-in. to 12-in.-long) cripple studs nailed to the double top plates of nearby walls. Sheathe the platform with l/’-in. plywood or OSB.

than with trusses, the ridge board can also run long at this stage. This process ensures a straight barge rafter. It also lets you straighten a bowed gable rafter. Hoist a supply of 2×4 lookout stock up to the roof, set each lookout in its notch, and secure the end of each one against the face of the first inboard truss (or rafter) with two 16d nails. Keep the top sur­face of the lookout flush with the top edge of the truss. Now, before driving a pair of 16d nails into each notch, move the gable-end rafter in or out to make the framing member as straight as possible. Nail all the lookouts in their notches, and leave them like this for now.

I Make truss ends straight

If the truss tails have been set straight, begin to cut and install the gutter or fascia boards. If they’re not straight, snap a line across the top or bottom edges, then mark plumb cuts to

I lineup the truss ends in the same plane. This is another exception to the “never cut a truss" rule. As long as you’re onlv making a small cutoff at the end of the truss (well away from joints and gussets), there’s no chance of struc­tural damage. Check the cave overhang called

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for in the plans. Measure this distance on the gable-end trusses at opposite ends of the house. Then snap a line across all the trusses, going from one end of the house to the other. Mark the cut lines on the truss ends and make the cuts. This technique also works when building plans call for exposed rafter tails that must be cut in the same plane. Use a iig or pattern, such as the one shown in the top illustration on p. 132, to mark identical plumb cuts on the rafter tails. You can make the cuts from above, while standing on the top plate of the wall, or from below, while standing on a ladder or seal Inkling.

Install the gutter or fascia boards

Although both gutter and fascia boards are nailed to the rafter tails, the distinction between the two is that gutter boards are later

covered with trim (aluminum or vinvl clad-

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ding or lx finish material), fascia, on the other hand, is a finished surface. Some builders install lx fascia boards over 2x gutter boards or subfascia, while others use the 2x stock as the finished fascia.

Obviously, smooth, accurate cuts are required to install fascia boards, while gutter boards are less demanding. On this house, we installed gutter boards that were latei clad with coil aluminum (see chapter 7).

On small houses, trusses are generally engi­neered to obtain their support from exterior walls without needing further support from interior walls. Still, its not uncommon for trusses to cross over and bear on interior walls. Inmost regions, these trusses can usually be nailed directly to the interior wall with two 16d toenails on one side and one on the opposite side. T his is not the case, however, if you live in a part of the country where the weather may be freezing one day and boiling the next. In areas with extreme temperature fluctuations, trusses must be able to expand and contract freely. Otherwise, drvwall ceilings

nailed to these trusses tend to crack. Check with your building department for the code requirements in your town or city. In addition, ask area builders what the local practice is.

To secure a truss to a wall while still allow­ing it to adapt to fluctuations in temperature and humidity, use a truss clip, as shown in the illustration above. These clips, which are nailed both to the wall plates and to the truss, feature a slot that allows the truss to move up and down as it expands and contracts— just make suie (lie nail is slightly loose in the joist chord.

Ceiling joists or joist chords

Dry wall nails

2×6 wall

Doing carpentry on the ground is easier than doing carpentry on top of the house. . .

You really have to watch your step. . .

We handle the trusses carefully. . .

Plenty of bracing is required to tie the trusses together and to the rest of the house. . .

When all the trusses are up, the house looks like an upside-down ship with the hull removed.

STEP5 Add Drywall Backing

At this point, you need to add backing (some­times called deadwood) to walls that run parallel to the joist chords. The backing pro­vides a nailing base lor ceiling drywall (see the illustration on the facing page). It’s easier to put the backing in now rather than after the roof is complete and hampered by sheath­ing. This is a good place to use knotty, crooked 2x stock. Nail the stock, one 16d nail every 16 in., to the double top plate of parallel walls so that the 2x backing overhangs the double top plate by at least 1 in. on both sides. Some builders use drywall clips instead of solid backing, but I like to fasten nails into some­thing solid. (Details on drywall installation are covered in chapter 9.)

This process is different for trusses that are allowed to expand and contract. In this case, nail flat 2×4 “ladder” hacking between the joist chords on a parallel wall. Use truss clips to attach the backing to the double top plate of the wall, as explained on p. 127. This allows the trusses to expand and contract without stressing the drywall.

STEP6 Install the Barge Rafters and the Fascia Boards

As explained earlier in this chapter, barge rafters extend beyond the end of a building, creating an overhang at the gable ends. The rafters are supported by 2×4 lookouts that fit into notches cut in the gable-end rafters. The lookouts run back to the first inboard rafter (or roof truss). At the bottom corner of the roof, a barge rafter meets a gutter or fascia board, which extends along the eave and is fastened to the ends of the rafter tails.

There are a few tricks to making sure that these exterior trim details are done correctly. If you plan to cover the trim with aluminum cladding, as we did on this house (see chapter 7), the culling and installation work is a little easier. On the other hand, if the barge rafter and fascia will be exposed as finished trim, youTl need to cut tight-fitting miter joints where the boards meet. Both types of installa­tion will go more smoothly if you follow the order of the steps described below.

Let the lookouts run long

I like lo install lookouts long, then snap a line from eave to ridge and cut the lookouts in place. If you’re framing with rafters rather

A hurricane can tear a roof completely off a house. Hurricane clips, which are designed to prevent this, are required by code in some parts of the country. After the trusses are nailed in position, hurricane clips are easy to install from inside or outside the house. Drive nails into the trusses and the top p. atesofthe wall (see the photo at left). Be sure to use the special short, strong “hanger” nails that arc sold with the clips.

In many parts of the country, frieze blocks are required between trusses. I’m in favor of these blocks, which you can cut from the plentiful supply of 2x scrap that your crew has been collecting. Installed at the top of the wall, these 2x blocks connect the bottom chords or, depending on the truss design, the rafters of adjacent trusses. They provide extra rigidity near the truss ends (see the illustration at left).

1 have seen firsthand how frieze blocks help hold truss systems together in high winds and earthquakes. They offer other benefits as well. The blocks can serve as exterior trim (with or without ventilation holes) if you plan to have an open soffit. If you are installing raised-heel trusses, as we did on this house, you’ll also need to install plywood or OSB baffles between the trusses to prevent attic insulation from spilling into the soffit area (see p. 51).

Install a pair of frieze blocks after each truss is installed. Drive a pair of 16d nails through the truss and into the end of the frieze block, then nail the frieze block to the top plate. You can cut a supply of blocks quickly on a chopsaw. Make sure you cut them to the correct length. If they’re toe long or too short, vou mav force the trusses off of their layout. The normal block length for trusses spaced 2 ft. o. c. is 22; in. However, if the

blocks will butt against gusset plates, you’ll need to take the gusset thickness into account. After vou’ve nailed the first frieze blocks

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to the gable-end truss, swing the next truss upright. Shift it right or left, as necessary, to obtain the correct cave overhang, then toenail it to the top plate with two 16d nails through the joist chord on one side and one 16d nail on the other side (see the top photo at right). Install the next several trusses in this fashion. As you raise each truss, tack a series of 16-ft. Ix4s (laid out 24 in. o. c.) near the ridge of the rafter chord to keep the truss stable and properly spaced (see the bottom photo at right).

An efficient way to work when installing roof trusses is to have a worker at each cave toenailing the truss to the wall and installing frieze blocks while one or two crew members work on the ridge, moving trusses into posi­tion and nailing 1×4 braces to maintain proper spacing.

Plumb and brace the trusses

When bracing trusses, take time to read and follow the directions from the engineering company. These, along with local building codes, must be followed to guarantee that the house will have a strong and stable roof. Most simple gable truss roofs are easy to brace.

After four to six trusses have been installed, plumb the gable-end truss and begin bracing the roof. Use a level to plumb the end truss, then install a diagonal 2×4 swav brace from the double top (cap) plate of the exterior wall (where the gable-end truss is installed) to an inboard truss (see the top photo on p. 126). The brace should extend at a 45-degree angle from the top plate and be nailed to the top chord (or At) or the webbing of an inboard truss.

INSTALLING PERMANENT BRACING INSIDE. Shown in the top photo, a diagonal brace from the top of a truss down to a wall plate helps hold the trusses plumb. Install a 1×6 or 2×4 catwalk on top of the trusses’ bottom, or joist, chord. The brace should be nailed into every joist chord and into the end-wall top plates (photo at right, above). Nailing 2x bracing across the webbing provides the roof structure with additional rigidity (photo at left, above). [Top photo by Roe a. Osborn

courtesy Fine Homebuihiinq magazine, The Taunton Press, Inc.]

If the gable-end rafter is plumb, the rafters tied to it at 24 in. o. c. should also be plumb. When all of the trusses have been installed, nail in a svvav brace at the other end of the roof. On longer roofs, use additional diagonal

swav braces near the center of the house to

і

further strengthen the roof.

The next step is to stabilize the joist chords by nailing a long board (a lx or 2x will do) on top of each joist chord near the center of the span. You can move this bracing to one side or the other if voи need to accommodate an opening for attic access (see p. 130). Nail this long brace to each chord with two 8d (for lx stock) or 16d (for 2x stock) nails (see the bot­tom right photo on the facing page). Addi tional 2×4 braces are often nailed at 45-degree angles across the underside of t ie rafter chords or webbing from the plate line to the ridge (seethe bottom left photo on the facing page). Nail these braces into each chord with two 16d nails. This provides lateral stability to the entire roof.

The first truss to be installed is the gable truss (also called an end truss or a rake truss) that rests on the top plate of an end wall. This truss is usually built differently from regular trusses. Instead of having angled web pieces, these end trusses often have vertical webbing spaced 16 in. or 24 in. o. c. to allow for easy installation of sheathing or siding.

Some carpenters like to sheathe end trusses with OSB and even finish siding before raising them upright (see the photo below). Another option is to cut all the sheathing pieces on the ground, raise the truss, and then nail the pre­cut sheathing in place. It is certainly easier to sheathe a truss on the ground, but it makes the truss substantially heavier and more clifti-

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cult to handle. If you do decide to sheathe the trusses before raising them, let the sheathing lap down below the ceiling joist chord by a couple of inches. T he lap will be nailed to the top plates once the gable is raised upright. This helps ensure a strong union between the truss and the wall, which is especially impor­tant in windv areas.

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Notch the gable-end truss

Notches for lookouts arc exceptions to the 11 never cut a truss" rule. Lookouts hold the barge rafters, which extend beyond the build-

INSTALLING THE LAST GABLE-END TRUSS. Unlike the other roof trusses, this one was sheathed on the ground and then hoisted into position.

ingline at each gable end to create a roof overhang (see the photos at right). Gable trusses can be notched because they are nailed directly over a load-bearing wall. As a result, the entire joist chord of each a gable-end truss is fully supported.

Its best to cut notches for 2×4 lookouts while the gable truss is still lying Hat. For the first lookout, measure and mark 48 in. from the end of the truss tail. Cut a 2×4 notch (which is actually I in. deep and 32 in. wide) below the first 48 in. mark and every 48 in. thereafter (see the illustration on p. 122). With the gutter hoard or fascia in place, 4-ft.-wide sheathing will fall on the lookouts.

CHOOSING NOT TO NOTCH. Some houses (especially in northern areas) are designed without gable-end overhangs so that more sunlight can get into the house. If this is how you plan to build a house, lookouts or notches are not necessary. Instead, fur out the rake

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board with lx lumber, so that t ic exterior siding tucks under it (see the illustration on p. 123).

Unless the trusses were set on the walls at the time of delivery, they must be hoisted onto the walls by hand (see the photo on p. 122). Oneway to do this is to set good, strong lad­ders at both corners of the building. If you’re dealing with long trusses, place a 2x in the center, from the ground to the top plate, at the same angle as the ladders. This way, two peo­ple can lift a truss, lay it against the ladders and the center 2x, and walk it up to the top. Another person in the middle with a notched pole can push on the truss as needed.

In preparation for installing the first truss the gable-end truss), I nail a long, straight.

Be aware of wind. Take care with trusses while the wind is blowing. Sheathed trusses can catch the wind like a boat’s sail. Even bare trusses can be difficult to control. If it’s windy, have extra helpers on hand and use extra bracing to keep installed trusses in place.

TRUSSES TAKE TEAM­WORK. A crew of four does a good job of getting roof trusses up on the walls. Using a long push stick, the ground worker helps elevate the truss.

temporary 2x brace on edge to the wall frame near the center of the end wall. This holds the gable-end truss stable until other braces are installed. If the truss is not too large, one per­son on top can drag the truss to the opposite end and lift it up against the temporary brace. Make sure that the cave overhangs are correct and that the outside of the bottom chord is flush with the outside of the end wall’s top plate. Toenail the bottom chord to the double top plate, driving 16d nails every 16 in.

STEP3 Install

the Remaining Trusses

Trusses by themselves arc rather fragile. They gain strength when they’re properly blocked and braced. I will now explain various block­ing and bracing strategies, because this work needs to be done as the trusses are installed.

Safely on the Job WORK SAFELY ON A ROOF

KEEP YOUR WITS about you and pay extra attention to what you’re doing when you’re up on a roof— both to keep yourself safe and to ensure that the integrity of the roof is not compromised.

ж To get on and off the roof, use a good, sturdy ladder that extends 3 ft. above the edge of the roof.

ж Keep the roof dean so that there won’t be any­thing to trip over.

ж Be careful when sawdust is on the roof. Sawdust on a sloped roof can be as slick as ice. To be safe, call out measurements to cutters on the ground and have them dear the board of sawdust before handing it up to you.

Never throw anything off a roof, not even a shin­gle, without first checking to see that no one is down below.

In the hot sun, asphalt shingles soften and tear. Walk gently so you don’t damage the shingles. In hot weather, install shingles early in the morning or late in the afternoon.

In bitter cold weather, shingles become brittle and crack. Work carefully, and pray for sunshine.

Shinglers who nail off a roof by hand often sit on the roof as they work. In hot weather, try sitting on a piece of foam while nailing shingles. Otherwise, hot shingles can literally burn your backside.

HURRICANE CLIPS TIE TRUSSES TO WALLS. Required by code in many areas, these metal connectors are designed to fit around the bottom chord of a truss and against the top plate of a wall. Here, a volunteer attaches a clip with an air hammer.

Mark truss locations Posted by admin on 17/ 11/ 15 Before trusses arrive on the job site, take some time to lay out their locations on the top of the wall plates. Hook a long tape on the end of the exterior walls and mark the entire length of the building at 2 ft., 4 ft., 6 ft., and so on, putting an "X" on the far side of each mark. Do the same on any long interior walls that run parallel to the outside walls. Mark the same 2-ft. o. c. layout on several straight 16-ft. 1x4boards. These lxs will later be nailed near the ridge to hold each truss upright at the proper spacing. Despite your best efforts to line the walls (asexplained in chapter 4), the exterior eave wall plates may not be totally straight. If you hold the truss overhang to a wall that is not straight, the rafter ends and fascia won’t be straight, either. There is an easv wav to remedy this. Measure 1 in. in from the outside at each end of the exterior wall’s top plate. Snap a chalkline the lull length of the wall to create a straight reference line. Make an alignment mark on the joist chord of each truss. Measure in from the end of the truss the planned eave overhang distance plus 1 in. When installing each truss, put the truss mark right on the plate’s snapped reference line. This guarantees that the truss ends are aligned. Habitat Houses—Built to Take a Licking Posted by admin on 17/ 11/ 15 THE MOST DEVASTATING natural dis­aster in the history of the United / States began to take shape off the west coast of Africa on August 14, 1992. Gathering strength as it made its way across the Atlantic Ocean, the storm that came to be known as Hurricane Andrew finally made land – fall at Homestead, Florida, just alter 5 a. m. on August 24th. With sus­tained winds of 145 mph and gusts exceeding 175 mph, Andrew was no run-of-the-mill hurricane. Although the death toll was relatively low for a storm of this intensity (40 people died as both a direct and an indirect result of Andrew), the economic damage exceeded $25 billion. As it turns out, Habitat had built or rehabbed 27 houses in Homestead and in the nearby communities of Liberty City and West Perrine. A few ^ 4 days after the storm, Kevin McPeak, Habitats regional administrative coordinator, drove out to survey the damage. Hoping for the best but bracing himself for the worst, Kevin was astonished and elated as he discov­ered, house by house, that everyone of the Habitat homes had survived Andrews onslaught. Carpets were ruined and windows were broken; a few houses had even shifted a bit on their foundations. But compared to most of the houses around them, the 1 Iabitat houses stood tall. Clearly, Habitat knows how to build houses. A BALANCING ACT. The ability to walk on the wall plates is helpful when installing roof trusses, but you can also do the work from a ladder or from staging set up inside the house.   ladder or a scaffold instead. To make it casv to move trusses into position, I like to build a catwalk, or walkway, over open sections, such as the living room. (For directions on howto erect a catwalk, see the illustration at right.) Materials METAL ROOFS Posted by admin on 17/ 11/ 15 METAL ROOFS HAVE been around for a long time. One of the outbuildings at our prairie home had a corrugated metal roof. It was rusty and rattled in the wind, but it shed water. Today, you can buy metal roofs in a variety of colors and styles. They are lightweight and fireproof and don’t hold heat the way asphalt shingles do. Metal roofs work well in snow country because they shed snow so well. With extra fasteners, they can be used in high wind areas, too. The initial cost of a metal roof is greater than that of a shingled roof, but a metal roof will last much longer. Roofs with concealed fasteners usually cost more than those with exposed fasteners. The neoprene gasket on an exposed fastener may leak after several years in the sun, so it will need to be replaced. In general, though, the upkeep on a metal roof is minimal. Metal roofing panels, ridge vents, and other components can be precut at the factory and installed with basic tools and simple instruc:ions supplied by the manufacturer. The most basic metal roofs are fastened to the roof structure through a standing seam that is raised above the drainage plane to reduce the chance of leaks. Cuts can be made on the job site with tinsnips or electric shears, which are often referred to as nibblers. IN THE DRY SOUTHWEST, open, exposed rafter tails are preferred. But elsewhere—especially in cold, wet locations—soffits are more popular. Eave soffits are usualLy vented. There are quite a few ways to frame soffits. The easiest way is to have the truss company extend the joist chord beyond the building line to form a level overhang. This is called a raised-heel truss. If the trusses do not have a raised heel, you can still build a soffit easily by sheathing the underside of the sloped rafte’ tails. For a level soffit, nail a long 2x to the building and sheath between it and the gutter board or subfascia. If only a fascia board is used, cut a groove near the bottom edge to sup­port the outer edge of the soffit board. No matter which type of fascia treatment you choose, make sure you install fire-stops between the studs to help prevent a fire in the wall from spreading into the soffit area. Check with your building department to find out which fire-stop details are required. A Roof Overhead Posted by admin on 17/ 11/ 15 THE WALLS FOR OUR HOUSE ARE UP and we now have something to show for our work. At this stage, we can walk through the structure; admire the view through rough window openings; and imagine how the finished siding, painted drywall, and floor­ing will look. But first, we need to raise the roof. Before we reach for a hammer, we need to make some decisions about. he roof trusses. We also have to prepare the site for their delivery and do some layout work so that the installation process can go smoothly. Once the trusses are installed, well move on to the fascia hoards, sheathing, and shingling. Roof Trusses Marly in my building career, 1 was taught how to lay out rafters with a site-made tem­plate containing the plumb and birds-mouth cuts. You can still cut and frame a roof one rafter at a time (see the 11ustrat ion on p. 114), but today most roofs are con­structed with factory-made trusses. Trusses are designed on a computer, built on an assembly line, and delivered to the job site ready to install. If you’re building a simple 5 Add Drywall Backing 6 Install the Barge Rafters and the Fascia Boards 7 Sheathe the Roof 8 Seal the Roof with Felt Paper 9 Ishingle the Roof V> ,y; .   Щ   шш ‘ ‘ ‘ &,/•:,. ••••••• >•;•,   Щї V^Sy*   г*І   sable-roof house like the one shown here, roof O’ trusses can save time and keep the construc­tion process simple—something that everyone will appreciate. kach truss includes a pair of rafters and a bottom chord that functions as a ceiling joist inside the house and as level soffit framing outside the house. Short lengths of wood, called webbing, connect the rafters with the bottom chord; barbed steel gusset plates [gus­sets, for short) are pressed into place over the joints to hold all the parts together. For a basic look at the different truss configurations, see the illustration on the facing page. The basic – roof installation process that we’ll use on this house will be very much the same for other 4 houses, regardless of size. Porch considerations On the house w»4v building, the main root extends over a small porch. In this situation, you need to have at least some of the porch framed before installing the roof trusses. Some builders choose to erect temporary posts to support the top beams on which the roof trusses (or rafters) will bear. When the porch is completed later, these temporary posts arc replaced with permanent ones. This strategy allows roof framing to follow wall framing directly, without the interruption of porch construction work. For details on how to build a porch or a deck that’s attached to the house, see chapter 7. Ordering roof trusses After vou make a few basic decisions about the trusses for vour house, it’s fairlv easv to order them. 1 like the raised-heel design of the trusses we used on this house (see the illustra­tion on the facing page). This type of truss provides an overhang along the cave walls as well as framing for a level soffit. Because the rafter is elevated above the wall’s top plate, there’s ample room for ceiling insulation and ventilation space above. 11 о woven, as shown in the illustration on the facing page, other truss designs are also possible. Depending on your budget and design preferences, you can use a scissor-type truss and have a cathedral ceiling inside the house. Or perhaps you like the rustic appear­ance of an open soffit and exposed rafter tails along the eaves. A good lumber dealer has different truss designs to show you, and it’s worth taking a look. Once you decide, here are the basic specifications the manu­facturer needs to design and construct vour trusses: 4 TYPE OF TRUSS. The major types of trusses for gable roofs are shown in the illustration above. SPAN BETWEEN EXTERIOR WALLS. The span is measured from one outside edge of the build­ing to the other. EAVE DETAILS. The amount of overhang at a building’s eaves is usually shown on the plans. The plans should also tell you whether the soffit will be open or closed. For details on different wavs to finish off an eavc, see the sidebar on p. I 1 7. NUMBER OF TRUSSES. Roof trusses are typi­cally spaced 24 in. o. c. Therefore, if your building is 40 It. long, you’ll need to order 21 trusses. SPECIAL REQUIREMENTS. If your house has a more complex roof, special trusses may be required where one roof section joins another. ROOF PITCH. Trusses for most small affordable buildings have either a 4-in-12 or a 5-in-12 pitch (see the illustration on the facing page). STEP 1 Prepare for Truss Arrival and Installation When roof trusses are delivered lo a job site, they can be offloaded onto the ground or onto the framed walls of the building (see the photo on the facing page). The choice depends on the builder’s preference and on the delivery truck’s capabilities. Experienced builders prefer delivery on the walls because it saves time. Whether vour trusses are offloaded onto / the walls or onto the ground, thev must lie flat. I have seen trusses that were stored on uneven ground come apart at the seams, mak­ing them useless within a couple of weeks. Until they are nailed upright in place, braced, and sheathed, trusses are actually quite fragile. Prepare а Паї area close to the house where the trusses can be offloaded. The bottom­most truss should not rest directlv on the 4 ground but on wood slickers that provide a flat, level base. Set up work platforms One of the most difficult parts of roof-truss installation is working high off the ground. It takes skill and practice to be able to stand on a narrow top plate and nail trusses to the wall. If this seems dangerous, or if you’re uncomfortable with it, try working on a Techniques SHEATHING A WALL Posted by admin on 17/ 11/ 15 WHEN ALL THE walls have been raised, braced, and lined, it’s time to attach the sheathing. On this house, two types of sheathing are used. 1. To provide shear bracing, OSB panels are installed on all corners and every 25 ft. along exterior walls. 2• Foam board sheathing is nailed to the framing between wood panels. It’s easier to sheathe right over window and door openings, then cut out the openings from inside. Foam cuts easily with a handsaw. Safety on the Job LADDERS FEW THINGS SCARE me more than working on a ladder. While they are frequently indispensable, ladders must be treated with the same respect as power saws. Here are a few tips to make working on a ladder safer: ж Don’t buy a cheap ladder. I like the heavy-duty, fiberglass models. Look for one with a 1A rating (the best) on the label. When buying an exten­sion ladder, be sure to select one that is long enough to extend 3 ft. above the height of your roof. ж Aluminum and wet wood can conduct electricity. It’s best to use a fiberglass model when working near electrical wiring. Don’t stand on the uppermost rungs. Get a longer ladder instead. When working on a ladder, you can lose ycur balance by reaching too far to the side. If your reach starts to feel precarious, it probably is. Get down and move the ladder. Don’t leave tools sitting on top of an unattended ladder. Make sure the ladder’s feet are firmly and securely planted on a solid surface before climbing up it. When using an extension ladder, tie it to the building at both the top and the bottom (this is particularly important if it’s a windy day). Since sheathing panels will he covered with finished siding, they don’t need to be installed perfectly. Earthquake- and hurricane-country sheathing codes are often quite strict, so check with your local building department before you start covering walls. Again, remember to insulate corners, channels, headers, and behind tubs before you attach wall sheathing. Install sheathing on the corners first Whether I’m sheathing all the exterior walls with wood panels or just the corners (as we did on this house), I always install sheathing on the corners first (see the bottom left photo on p. 109). To hold a sheet in position while you get ready to nail it, try driving a couple of 16d nails near the bottom of the wall. Keep plywood and OSB ‘A in. away from a masonry At first, we’re not worried about making sure the are plumb or straight—we just keep them up with dio braces. . . foundation. If the stud layout is correct, the edge of the first panel should fall on a stud 4ft. from the corner. In humid areas, leave a! йі. expansion gap between sheets. If a sheet doesn’t break on the center of a stud, rip the sheet to fit, move the wall stud, or put in an extra stud. You can sheathe right over windows and doors and cut them out later with a recipro­cating saw. Use scrap pieces to fill in gable ends and underneath windows or to cover rim joists. 1 also sheathe various walls inside the house, though this goes beyond most codes. Ido this because 1 know that a lew extra sheets of OSB might save someone’s life dur­ing an earthquake or a tornado. Sheathing the back wall of a closet, bathroom, or utility room gives the frame extra lateral stability. In areas prone to serious tornadoes, you may be required to create an entirely sheathed and well-anchored safety room in which house­hold members can gather during a storm (see Resources on p. 278). The nailing schedule for sheathed walls often requires 8d or 1 Od nails at 4-6-12. This means that nails are spaced 1 in. around the perimeters of walls, 6 in. at the joints between sheathing panels, and 12 in. in the field. Check with your building department for the required nailing schedule in your area. Install foam sheathing There are many areas in the country where plywood or OSB sheathing is required only at exterior corners and everv 25 ft. along exterior walls. This allows you to install nonstructural sheathing material everywhere else. On this house, we used [2] -in. foam sheathing. The foam board is light and easy to handle, though it can be damaged by a stray hammer blow or O j I by someone stepping on it. Attach foam sheathing with roofing nails. Sheathe right over window openings, then go inside the house with a handsaw and cut out the loam from the openings (see the bottom right photo on p. 109). If you’ve come this far, vou and vour con – struction crew deserve some heartv congra – filiations and a little time to rest before tack­ling the roof. Getting wa Is framed and sheathed is a huge step forward in the con­struction process, and it demands brainpower for accurate layout and lots of energy to pound nails and raise walls. Make sure you spend some time cleaning up the job site at this point in your project. There are bound to be plenty of offeuts, such as 2x stock, plywood or OSB scraps, and stray fragments of foam sheathing. Remove the debris and get set to raise the roof. lien we start finding the exact positions with a level к soon as the exterior walls ore up, we start on the It’s amazing to think that just о short while ago, we had only piles of lumber and a bare floor. . . This is going to be a great house!   … "ШИ II-*• – *’ ■ИГГ1 .чи !!ЇііііЩ#і!   CHAPTER   « Previous 1 … 7 8 9 10 11 … 15 Next » Tweet Copyright © 2025 Library builder - Articles about the repair, construction, interior design and landscaping, plumbing, electrical, waterproof wire, wire gas, building materials, construction machinery and equipment ...