Category Habitat for Humanity International

Mark exterior walls first

Posted by on 14/ 11/ 15

If the deck perimeter isn’t parallel and square, the walls won’t be either. Take the time to check this now, following the procedure explained in chapter 3 (see pp. 54-56). If nec­essary, lino-tune the exterior wall layout to correct for out-of-square corners or nonparal­lel walls. The lines you snap define the inside
edge of the exterior walls. For 2×4 walls, mea­sure ЗV: in. in from the deck edge (slightly more or less if you need to get the walls square and parallel). If the walls will be framed with 2x6s, use a 5’/-in. measurement. Instead of measuring this distance, you can simply lava scrap 2×4 (or 2×6) on the deck and mark against its inside edge. Mark all the exterior corners to establish the layout marks for snapping the exterior wall lines around the perimeter of the floor (or slab).

When you’ve marked all the comers, snap lines around the perimeter. If you’re working on a concrete slab, vou may want to move all these lines in an extra / in. so that the wall sheathing can be nailed onto the framed wall flush with the concrete. At this po nt, pay no attention to the openings for doors and windows—just snap the wall lines right through the openings.

Mark interior walls next

Begin laying out the interior walls by measur­ing from the exterior walls. For example, the illustration on p. 77 calls for a distance of

Mark exterior walls first12 ft. 7 in. from the outside comer of the house to the center of л partition wall. Add or subtract VA in. from that distance to snap the layout line for the partition wall. Remember to note how measurements are given on the plans. Layout long interior walls (such as hallways) first, then do the short walls (such as closets). There is no need to mark the door and wall openings.

For hallways, the minimum width is 37 in. in the rough, which yields a finished width of 36 in. (accounting for ‘A-in. drvwall installed on each side). I sometimes frame hallways 40 in. wide in the rough to create easier pas­sage tor a wheelchair (a standard wheelchair is 26 in. wide).

Pay particular attention to squaring bath­rooms and kitchens, which makes it easier to set cabinets and install vinyl flooring. When framing on a slab, plumbing lines will have been set in the concrete. If a pipe was placed slightly outside where a wall should be, its better to move the wall rather than the pipe. If the pipe misses the wall by a lot, you’ll need to involve a plumber.

Although a standard bathtub is 60 in. long,

I snap wall lines with a 60’Ain. space for the tub, which makes installation easier for the plumber. 1 also lay out the bathrooms plumb­ing wall with a 2×6 wall instead of a 2×4; a wider wall makes it much easier to fit all the bathroom pipes inside.

STEP2 Plate the Walls

This step involves laying out all of the lumber required for the top and bottom plates, cut­ting the plates to length, and temporarily tack­ing them on their layout lines so that match­ing marks can be made on both plates for the studs, doorways, windows, and ntersecting walls. Don’t plate, mark, and build one wall at a time. This old method is time-consuming
and makes it difficult to frame accurately. Instead, put all the plates down for every wall, beginning with the outside walls.

Подпись: Helping HandПодпись: "Tacking" is temporary. When a framing carpenter uses the word "tack," it means that parts are temporarily nailed together.It’s best to plate the long, outside through walls first, then plate the outside butt walls that extend between the through walls. As shown in the illustration above, through walls have plates that run through them from cor­ner to corner. Walls that ft between or inter­sect other walls are called butt walls. After vou finish plating the outside walls, you can move inside, beginning with the longest walls and working your way toward the shortest ones.

. FROM PLANS TO PLATES

Posted by on 14/ 11/ 15

Подпись:—4-

Chalklines are snapped on the floor to show the location of all the walls. The top and botzom plates will be tacked to the deck along those lines.

. FROM PLANS TO PLATES

plates temporarily tacked together on the sub – floor, you can mark up the plates to identify exactly where each stud, king stud, header, and trimmer is located. If you haven’t already done so, take the time to familiarize yourself with the various parts that go into a wood-frame wall (see the illustration on p. 84).

Mark wall layouts

Three marking tools are essential: a chalkline, keel, and a carpenter’s pencil. A chalkline and an ample supply of chalk allow you to snap exterior and interior wall layout lines on the

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sublloor or slab (see the photo on p. 78). It’s not necessary to mark two lines for a wall; instead, use a carpenter’s crayon, or keel, to mark an “X" on the side of the line that will be

LAYOUT STARTS WITH SNAPPED LINES.

. FROM PLANS TO PLATESThe floor deck is clear, but not for long. Snapped chalklines identify where the walls will be located.

Подпись: Helping HandПодпись: An awl helps during solo layout. When working alone to mark measurements on wood floors, use an awl to hold the chalkline or measuring tape in place. If you don't have an awl, a nail will do.. FROM PLANS TO PLATES

covered by the wall plates. Keel is also useful for labeling parts, writing cripple sizes on headers, and indicating door and window – openings.

To make a snapped line easier to find, use a pencil or keel to make a crow s foot, or a large “V” mark, with the point centered on the line. If you snap a line in error, wipe it away with your foot or at least draw a wavy line through it before snapping a line in the correct place. Use a carpenter’s pencil to make stud layout lines on the plates. Try to keep all markings clear and simple, and avoid complicating things unnecessarily. The object is to get all the information you need off the plan and onto the floor in an understandable format.

Ace

Posted by on 14/ 11/ 15

WHETHER YOU’RE AN EXPERIENCED BUILDER, A HABITAT VOLUNTEER, ora novice carpenter, the wall-framing phase of a homebuilding project is especially exciting. Piles of lumber scattered around a flat platform are soon assembled into a complex skeleton that defines the shape and si/.e of a homes interior spaces. For the first time, it’s possible to experience the look and feel of a new house, identifying where bed­rooms and bathrooms will be and enjoying the view through rough window open­ings. We’re still a long way from move-in condition, but the completed frame is a dramatic step forward.

Although quite gratifying, framing walls is also hard, intense work. It requires an abundance of energy, good teamwork, and real presence of mind. As you’ll see on the following pages, it takes quite a few steps to got the walls up and ready for roof trusses. Wall locations must be chalked out on the slab or subfloor; plates must be scattered; headers, rough sills, cripples, and trimmers must be cut; plates must be marked; and the pieces must be nailed together. After the walls are nailed together, they must be raised, braced, connected, plumbed, lined, and

Подпись: STEP BY STEP

1 Lay Out the Walls

2 Plate the Walls

3 Count and Cut the Headers, Rough Sills, Cripples, and Trimmers

4 Mark the Plates

5 Build the Walls

6 Raise the Walls

7 Plumb and Line the Walls

8 Install and Plumb Door and Window Trimmers

9 Sheathe the Walls

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Ace

Подпись: Helping HandПодпись: Select the right chalk. The powdered chalk used for chalklines comes in different colors. Have a second color on hand, in case you need to snap a new chalkline close to an incorrectly snapped line. If you need to lay out walls in wet weather, use waterproof chalk to make sure your lines stay sharp and precise. Подпись: 1 WALL DIMENSIONS ON PLANS Подпись: S Outside to outside 4 Outside to center V 4 4 ^ V Wall to wall Подпись: Center to center — Ac-cepter to center is the same as wall to wall. Подпись: Dimensions on plans can be shown in different ways. Make sure you know the beginning aid end points of your measurements before laying out any walls.

sheathed. It all happens fast, though, and before you know it, there’s a house standing where there wasn’t one before.

As a novice carpenter, I was often afraid that 1 would make a huge mistake while doing wall layouts. Transferring measurements from the building plans to the floor sheathing or slab seemed like a precise and unforgiv­ing science, the principles of which I didn’t fully understand. I knew that once the house was framed, the wall-layout lines would be real spaces—bedrooms, bathrooms, and kitchens—so accuracy seemed critical. After

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laying out a few houses, however, I learned that, as with most other aspects of carpentry, wall layout just needs to be close—normally within :4 in. tolerance—not accurate to a

machinist’s or scientist’s tolerances. After I realized that, I was able to relax and get on with the work.

STEP 1 Lay Out the Walls

I’ve done plenty of house layouts on my own, but its better to tackle this job with a helper or two. The work goes faster when you have someone else to hold the other end of the tape or chalkline. More important, your chances of catching mistakes improve significantly.

Read the building plan

A building plan is a guide, just like a road map. There are symbols and measurements to tell vou what to do (see the illustration on the

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facing page). You don’t have to visualize every detail on a road map to get from Texas to Maine. Neither do you have to visualize every detail on a plan to be able to build a house. You just have to know how to read the plan, then take it one step at a time.

The most common plan scale uses / in. to equal 1 ft., so l in. on a plan equals 4 ft. on a subfloor. Plan dimensions, however, can be labeled as outside to outside, outside to center, or center to center (wall to wall), so you need to pay close attention to this information (see the illustration at left). For layout purposes, if you encounter an outside to center (o/s toe) dimension, simply add I M in.—half the width of a 2×4—to the overall measurement to obtain the outside to outside measurement, which you can then transfer to the floor. (For a 2×6 wall, add 2і/ in.)

The first layout work involves transferring key information from the building plans to the subfloor or slab. These lavout lines enable

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you to lay down the top and bottom plates for every wall in the house—a process called plat­ing the walls. With each wall’s top and bottom

Techniques FITTING SHEATHING

Posted by on 14/ 11/ 15

SOMETIMES A LITTLE extra persuasion is needed to unite tongue-and-groove sheathing panels. Have one person stand on the edge of the sheet and hold it flat and snug against the previous row of sheathing. Another person can lay a scrap of 2x (to protect the groove from damage) against the sheet and hit it with a sledgehammer. A couple of licks should bring the two sheets together. If not, check the edge for damage or for an obstruction that may be holding the two sheets apart.

Techniques FITTING SHEATHINGCOAX PANELS INTO PLACE. A couple of good wallops with a sledge will usually seat even an ornery Sheet Of tongue-and-grOOVe Sheathing. [Photo by Roe л. Osborn, courtesy Fine Homebuilding magazine, The Taunton Press, Inc.]

line. On one side of the building, measure in 48УІ in. at each end and snap a chalkline across the joists. The first row of sheathing is laid and nailed directly on that line. Getting this first row straight makes it easier to lav all sub-

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sequent rows.

Подпись: ,w?Lay down a full К-in. bead of construction adhesive on the joists beneath each sheet just before setting it in place (see the photo at left). This makes the floor structurally stronger and cuts down on squeaks in the future. Lay the first sheet with its grooved edge right along the control line, with one end on the center

SHEATHING MUST BE GLUED AND NAILED. Use a caulking gun to apply a bead of construction adhesive to the joists’ top edges before installing the floor sheathing. The adhesive strengthens the floor and helps reduce squeaking in the future.

 

Techniques FITTING SHEATHINGTechniques FITTING SHEATHING

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ofa rim joist and the other end landing mid-joist—8 ft. to the left or the right. If a sheet doesn’t fall on the center ofa joist, try pushing the joist over a bit. If this can’t be done, mark the sheet to length so the edge will land mid-joist, then snap a chalkline and cut the sheet. Finish sheathing the first row before moving on to the second one.

The second row of sheathing is installed much like the first, except that you begin with half a sheet (a 4-ft. by 4-ft. piece). This stag­gers the joints, which makes for a stronger floor. If you re building in a humid climate, leave about % in. between the ends and the edges of the sheets to allow for expansion.

This gap can be gauged by eye or by using an 8d nail as a spacer. The 14-in. gap between sheets means that vou will have to trim an end now and then so that each sheet lands squarely on a joist. Some manufacturers make sheets % in. short to allow for gaps and elimi­nate the need to cut sheets.

When plumbing pipes are installed before the sheathing, vou must lav out and cut holes in the sheathing. The easiest wav 😮 lav out these cuts is to measure from the edges of sheathing already in place to the center of the pipe, then transfer those measurements to the sheet that the pipe will go through (see the illustration on the facing page). Cut the holes somewhat larger than the pipes, using a circu­lar saw to make a plunge cut, as shown in chapter 2. This makes it easier to lift the sheet and set it in place over the pipes. Later, seal the holes well to keep cold or moist air from entering the living space from below.

Secure the sheathing to the joists with 8d nails

When the last panel in a course of sheathing extends beyond the rim joist, cut it flush with

the rim joist before nailing it down (see the photo above). The typical railing schedule for sheathing is 8d nails 6 in. o. c. around the perimeter of the building and at joints between the sheets and 12 in. o. c. in the field (the middle of the sheets). It’s best to nail the sheets soon after laying them, especially in hot weather, so that the adhesive doesn’t have a chance to set before the sheet is pulled fast to the joists. If necessary, snap chalklines across the panels to show the joist locations for nailing.

An efficient method is to have one team lav

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sheets and tack them at their four corners, then have another team follow behind, nailing off the sheets completely. In many areas of the country carpenters use rough-coated, hot- dipped galvanized nails or nails with grooves cut in them (ring-shank nails) to ensure that the sheathing stays firmly secured to the joists.

Walls Create Sp

Tool Talk MAKING A BLOCK-CUTTING TOOL

Posted by on 14/ 11/ 15

MANY CARPENTERS CUT BLOCKS with a

 

chopsaw, which is fine if you have one. But there is another easy way to cut blocks. Try making a simple block-cutting tool to use with a circular saw. Once you have the guide, simply hook it on a 2x and make the cut along the edge.

 

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MAKE A JIG TO CUT BLOCKS QUICKLY. This simple jig can be made from scrap in just a few minutes. It eliminates all measuring and marking, which saves a great deal of time when cutting blocking.

 

Tool Talk MAKING A BLOCK-CUTTING TOOLTool Talk MAKING A BLOCK-CUTTING TOOL

Tool Talk MAKING A BLOCK-CUTTING TOOL

job site, as I-joist width varies from manufac­turer to manufacturer. T he most common width for residential 1-joists is 9’/ in., so you can cut blocking from scrap pieces of I – joists or from 2×10 lumber. Cut the blocking to lit snugly between the chords of adjacent I – joists, and nail the blocking to the chords.

When nailing blocking between joists, it’s best to begin at one end of the house and sim – plv work your way toward the opposite end. Sight down the length of the first joist (the one closest to the rim joist) and make sure it is running straight. Measure the first joist space and cut the block to length. Set the block on edge over a girder or a crib wall. Drive two 16d nails through the rim ioist into the block and two 16d nails through the floor joist into the block. Next, angle a I6d toenail through both sides of the joist into the girder. Nail lapping joists together with two I6d nails. Sink one 16d toenail through each joist into the girder and angle a 16d toenail down
through the block at each end into the joists they span.

Once you have a few blocks nailed in place, use a tape measure to make sure the joists are maintaining an accurate o. c. layout so that the sheathing will land mid-joist. 11 necessary, cut the blocks a bit short or long to maintain accurate spacing.

In many parts of the country, rough plumbing and heating ductwork are installed before the floor is sheathed, so be sure to check with those contractors before sheathing. Also, find out whether you need a floor joist inspection before you install the floor sheathing.

STEP8 Install the Floor Sheathing

Before plywood and OSB were readily avail­able, we sheathed floors with softwood 1x6s that were cut and nailed diagonally across the joists. To make the joints between the 1×6
boards, the ends of each board were cut at a 45-degree angle. Frequently, the 1×6 lumber was of poor quality and had large knots. I still have scars on my lower legs from breaking through subfloors while working on job sites decades ago. The sheathing panels we use todav are much better than 1×6 boards—vet

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another improvement over how houses were built in "the good old days.”

Sheathing with 4xtS sheets of tongue-and – groove plywood or OSB is not difficult, though the sheets can be awkward to handle. Carry them with a partner, if necessary, and take care not to damage the tongues or the grooves, which can make X more difficult to fit the sheets together. Be sure to use exterior – grade, л-in.- or %-in.-thick sheathing.

Snap a line to lay out the first sheathing course

Подпись: Helping HandПодпись: That empty feeling. When installing sheathing, you can feel when a nail doesn't hit a joist—it goes in too easily. Driving a fresh nail to the left or right of the dud usually results in solid contact. When laying out long rows of 4×8 sheathing, its best to start from a control, or reference,

Techniques CUTTING SQUARE WITHOUT A SQUARE

Posted by on 14/ 11/ 15

ONE OF THE MOST important skills a carpenter learns over the years is training and trusting his or her eye.

And one of the best ways to develop this capability is to cut square by eye. Instead of using a square to mark a 90-degree cutoff line on a board, simply make a quick pencil mark for length on the board, line up a circular saw, and make the cut. Over the course of framing a floor or a wall, this method can save you plenty of time.

If you’re comfortable using a circular saw, it’s not difficult to master this technique. Position the saw with the blade aligned on the cutoff mark and the front of the saw’s base parallel with the edge of the board. As you make the cut, keep the base parallel with the board’s edge. Practice a few times on scrap, check each cut, and adjust the angle of the cut until you’ve got it right. Ir time, you’ll develop a "feel" for square.

Techniques CUTTING SQUARE WITHOUT A SQUARETechniques CUTTING SQUARE WITHOUT A SQUAREMAKE SQUARE CUTS BY EYE. To make a square cut, put the blade on the cut line and keep the front edge of the saw base parallel with the board.

Подпись: NAILING BLOCKING AT LAPPED JOISTS Подпись: Lapped joists spaced at 16 in. o.c. require a block about 13 in. long between the joists.

between the rim joists and the interior girders or crib walls in the basement or crawl space of an old house. Stress tests have long shown that bridging provides little extra stability to a floor sheathed with plywood or OSB. My experience is that most midspan bridging docs little except increase floor squeaks.

Blocking between joists, on the other hand, helps stabilize a building and keeps the joists from falling like dominoes under severe lateral stress, such as that generated by an earthquake or high winds. Blocking is installed at the bearing points where joists cross girders or crib walls. On many houses, this is also the spot where joists from opposite sides of the building lap against each other (see the illus­tration at right). To quickly cut dentical blocks with a circular saw, use a jig like the one shown in the sidebar on p. 70.

If you1 re building with I-joists, you’ll need to determine the length of the blocking on the

Подпись:Techniques CUTTING SQUARE WITHOUT A SQUAREі

Helping Hand

Call for inspection. Don’t forget to call for an inspec­tion of the joist system, the rough plumbing, and the ductwork once they are in place. Before the inspec­tor arrives, remove all scraps of wood and other organic matter from the crawl space.

Habitat Builds Barrier-Free Homes

Posted by on 14/ 11/ 15

Habitat Builds Barrier-Free Homes

SIMPLE, SINGLE-STORY HOUSES are

not only inexpensive to build but also lend themselves well to barrier-free (handicap-аccessible) eonstruction.

In addition to the obvious differences that relate to wheelchair accessibility—

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wider hallways and doorways, a ramp instead of a stairway at the entrvwav—

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many other smaller details help make these homes easier for their owners to use and enjoy.

The key to building or retrofitting a house for wheelchair accessibility is recognizing the modified reach of a seated person. You can start by raising the position of electrical outlets and
lowering the height of light switches, closet poles, shelves, and countertops. These easily made alterations help make day-to-day life more convenient for someone in a wheelchair.

Bathrooms and kitchens require special attention. Plenty of strategically placed grab bars are important; place them around the toilet and in and around the tub/shower. Extra space in the bathroom—so a wheelchair can get in and maneuver around—is essential, too. In the kitchen, lowered stovetop, sink, and cabinets help make it possi­ble for someone in a wheelchair to prepare and serve meals and clean up.

Recognizing the increasing need for barrier-free housing, the Knox­ville, Tennessee, Habitat affiliate spon­sored a contest to design an adapt­able, inexpensive, barrier-free house. Two designs were selected as winners; both are available to any affiliate through Habitat for Humanity Inter-

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national. With the leading edge of the baby-boom population already past 55, and modern medicine keeping us alive ever longer, more and more of us may come to appreciate housing that’s flexible enough to adapt to our needs as the years go by.

-Vincent Laurence

MODIFY CABINETS FOR WHEELCHAIR ACCESS.

Lower countertops and desk-type openings can make the kitchen much more accessible.

[Photo by Steve Culpepper, courtesy of Fine Homebuilding magazine The Taunton Press, Inc.|

Techniques FRAMING HEADOUTS

Habitat Builds Barrier-Free HomesHabitat Builds Barrier-Free Homes

SOMETIMES JOISTS MUST be cut to allow room for a stairway, a heater vent in the floor, or a tub trap in the bathroom. Such an opening is called a headout. As shown in the illustration at right, regular 2x joists (not I-joists) can be cut and supported by a header joist that is fas­tened to parallel joists. If the opening is larger than 4 ft., double both the side and the header joists. Attach the doubles with 16d nails spaced 16 in. o. c.

A common mistake made by carpenters framing a headout is not taking into account the thickness of the header joists. Remember to factor in these joists when determining the size of your floor opening. If, for example, you need a 2-ft.-Long floor opening, cut the joists at 2 ft. 3 in. to leave room for the single-header joist at each end. For double-header joists, cut the joists at 2 ft. 6 in.

Подпись: NAIL OFF 2x JOISTS. To install 2x joists, drive a pair of 16d nails through the rim joist into the end of the joist. Then drive a toenail through each side of the joist into the sill.

Roll and nail the joists

Once the joists arc cut to length and in posi­tion, carpenters say that it’s time to “roll” them. This just means setting the joists on edge, aligning them with their layout, and nailing them in place. If you are working with 2x joists, it’s important to sight down each joist to see whether there’s a how or a crown, and then set the joist with the crown facing up.

Drive two 16d nails through the rim joist directly into the end of the joist—one nail near the top and one near the bottom (see the photo at right). Most codes also require that joists be toenailed (one 16d on each side) to the sill plates and supporting girders. To nail off an 1-joist, drive a 16d nail through the rim joist and into each chord, then nail the chord to the sill on both sides of the web.

Подпись: Г IПодпись: Helping HandПодпись: Make blocking from bad joists. When using 2x lumber for joists, avoid boards that are bowed or twisted or have large knots. Set them aside, then cut them up for blocking.Make sure that all the joists are nailec. securely. This is important for safety reasons, for quality workmanship, and for meeting the building inspection. Once all the joists are nailed upright, stop and check for symmetry— make sure the line of one joist is parallel with another. This is an easy way to spot layout mistakes. Take the time to check the framing against the details shown on the plans. Cor­rections are much easier to make now than after the floor sheathing is installed. Enjoy the moment. Joists on edge are beautiful in their own right, clearly and unmistakably showing the promise of a new building.

STEP7 Install Extra Joists and Blocking

Until recently, extra joists were often required under walls that ran parallel to the joists, because they helped support the roof struc­ture. Most houses built these davs use roof

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trusses, however, which are engineered to span from outside wall to outside wall without the need for interior support. There usually isn’t a need to install extra joists under walls, though some local codes still require them. Check with your town or city building department to make sure.

Similarly, wood or metal bridging is no longer required. Installed in crossed pairs between joists, bridging is often visible

Nail rim joists first

Posted by on 13/ 11/ 15

Rim joists form the exterior of the building and are the first joists to he installed. The lay­out of other joist locations are marked on the top edges of the rim joists. Cut the rim joists to length and toenail each one flush with the outside of the sill. I drive one I6d nail every 16 in. around the perimeter (see the photo below). In earthquake and high-wind areas, code may require that the rim also be secured to the sill with framing anchors, so check with
your local building inspector. If there are no vents in the foundation, they can be cut into the rim joists. A standard screened vent fits in a 41^-in. by 14^-in. opening.

If you’re framing a floor with 1-joists, you’ll probably use the specially made OS В rim joists supplied with your I-joist order. Install rim joists along only one side of the house. Then lay the I-joists flat across the sills, butting the end of each joist fast against the installed rim joist. The opposite ends of the joists will extend over the sill at the other side of the house. You can now snap a line across the ends to establish where the I-joists need to be cut. A simple jig, explained in the sidebar on the facing page, makes it easy to cut the joists smoothly and accurately. After cutting the I-joists to length, complete the rim joist installation.

Joist layout goes quickly

When a single joist spans a house from edge to edge, the layout is identical on parallel rims, lust hook a long tape on the end of the rim joist and make a mark on top every 16 in.

(32 in., 4cS in., etc.) down the entire length. Put an “X” next to each mark to indicate which side of the line the ioist goes on.

When the joists la}-» over a central girder or wall, the layout on the opposing rim joists must be staggered. On one rim joist, mark the 16-in. o. c. locations with an “X" to the right; on the opposite side, lay out the joists with an “X" to the left. T his allows the joists to lap and nail over a girder or crib wall, where they will be stabilized with blocks (see the illustration on the facing page).

Your joist layout may include openings (called headouts) for a stairway or to provide clearance for plumbing or vents. Your plans

Nail rim joists firstNail rim joists first

Tool Talk I-JOIST CUTTING GUIDE

I-JOISTS ARE AWKWARD to cut because the top and bottom chords are wider than the web. To overcome this difficulty, make a simple jig with УИп.-thick plywood. Cut a rectangular piece of plywood to fit between the chords and serve as the base of the jig. Screw a longer piece to the first p’ece, positioning it to guide a 90-degree cut. The edge of the top piece guides the base of the circular saw, as shown in the photo. Lay the guide on the I-joist, set the saw on it, and make a square cut. It’s that simple.

CUT I-JOISTS WITH A GUIDE. Scrap sheathing that is nailed or screwed together creates an effective guide for cutting I-joists. [Photo by Roe A. Osborn, courtesy Fine Homebuilding magazine, The Taunton Press. Inc.]

Подпись: JOIST LAYOUT Подпись: If a single joist spans from rim to rim, the layout is identical on each rim. When joists lap midspan, the layout on opposing rim joists must be staggered.

should show these openings, but it s always a good idea (and it could save a lot of time and effort) to check with the plumber. A common mistake is leaving insufficient room between the joists for the tubs trap and the toilet’s

drain. You mav need to frame a headout to

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make room for plumbing. For headout tram ing details, see the sidebar on p. 67. When framing with 1 joists, remember that, like any other type of engineered joist, they cannot be notched or cut midspan without destroying their structural integrity.

Cut the joists in place

If you trust your eye, try cutting 2x joists in place rather than measuring each one individ­ually. As you become comfortable using a cir­cular saw, you’ll be able make a square cut without using a square (see the sidebar on p.68). This technique is definitely worth learning. Over the course of framing a house, it will save a significant amount of time.

Safety on the Job PNEUMATIC NAILERS

Posted by on 13/ 11/ 15

Safety on the Job PNEUMATIC NAILERS

FOR THE MOST PART, volunteers who help build Habitat houses use only hammers to drive nails. But these days, buildings are often nailed together with all kinds of pneumatic nailers. These tools have been around for 40 years or so and are generally good, reliable tools. Models are available for framing, fin­ish work, siding, and shingling. However, as with all power tools, there are basic safety considerations to keep in mind.

♦ Treat a pneumatic nailer with respect. Be mind­ful of what you are doing. Never point a nailer at yourself or at others.

♦ Read and follow the instruction manual regarding

its maintenance and use.

♦ Don’t walk around with your finger on the trigger. You could bump the nailer against your leg, releasing the safety and accidentally firing a nail.

♦ Adjust the air pressure as needed. Larger nails require more pressure.

♦ Wear safety glasses or goggles.

♦ Disconnect the nailer from the air compressor before clearing a jammed nail.

♦ When nailing on a sidewall, don’t hold the nailer in front of your face. Hitting a metal strap or other hardware beneath the surface could cause the nailer to recoil into your face with consider­able force.

Safety on the Job PNEUMATIC NAILERSПодпись: I-JOISTS ARE LIGHT, STRONG, AND UNIFORM. Rather than using 2x lumber for joists, many builders prefer to install factory- made I-joists.

STEP6 Install the Joists

Joists span a house from edge to edge, provid­ing support (and a nailing surface) for the subfloor and a platform for the walls. Many older houses were built with undersized joists that were unable to keep floors and ceilings from sagging. Building codes today help ensure that joist sizing and spacing are more than adequate to keep floors rock solid yet resilient. Joists are normally spaced to allow for the most efficient use of full-size (4-ft. by 8-ft.) sheets of OSB or plywood. Joists cut from 2x lumber are generally spaced 16 in. or 24 in. o. c. Engineered wood I-joists can be spaced on centers of 12 in., 16 in., 19.2 in., or 24 in.

Solid lumber vs. engineered I-joists

Up until 20 years ago, most of the floors in this country were built with standard 2x joists. These days, more floors are being built with engineered I-joists. So named because of their Tprofile, I-joists have plywood top and bot tom chords connected by an OSB web (see the
photo above). They offer several advantages over solid lumber. Being an engineered prod­uct, they are knot-free and can span long dis­tances without interior support. I-joists don’t swell, shrink, crack, or warp the way solid lumber does. They are much lighter and easier to carry than 2x joists. And they’re uniform in size. In a load of 2x joists, you might find up to % in. of variation in joist width. I-joists don’t vary; once installed, they create a dead-

Подпись: Helping HandПодпись: Patterns save time. When cutting multiple identical pieces of framing members, such as joists, it is common to use a pattern piece. Cut one piece to the correct length, then lay it on top of the next piece to be cut and mark that one. Write the word "pattern" on the original piece.Подпись: INSTALL THE RIM JOISTS. The outside face of the rim joist (also called a band joist) must be flush with the outside edge of the sill. Toenail each joist to the sill, spacing 16d nails 16 in. o.c.

level floor. Nails driven through the sheathing into the top chord arc less likely to come loose and create a squeaky floor, especially when the sheathing is applied with adhesive. In terms of price, they are competitive with standard – dimension lumber. Installation details foi­l-joists are slightly different than those for 2x joists. I ‘ll cover those differences just ahead.

Techniques TOENAILING BASICS

Posted by on 13/ 11/ 15

Подпись: plate start the nail at a 60' angle, about 1 in. from the end of the board.Techniques TOENAILING BASICSПодпись: When it’s not possible to drive a nail directly through one piece of wood and into another, join them with a toenail.DRIVING A COUPLE of nails through the side of one 2x into the edge or face of another creates a strong connection. This is a good way to join two 2xs at a right angle. But sometimes this isn’t pos­sible, either because the board is too thick or because its face is not exposed. That’s when you resort to driving a nail at an angle, or toenailing.

To toenail two boards together, hold the nail at a 60-degree angle and start it about 1 in. from the end of the board. If the nail angle is not cor­rect, the connection between the two pieces of wood will not be as strong. Back up the wood with your foot to hold the board in place as you toenail. With practice, you’ll soon gain skill, speed, and confidence.

MEASURING POST OR PONY-WALL STUD LENGTHS

Techniques TOENAILING BASICS

Stretch a string tightly from one sill to another. For the post length, measure from a oiece of girder stock to the taut string. To find the stud lengths for a pony wall, measure from the top of a stack of three wall plates to the string.

 

walls stticis, stretching a line above a piece of girder stock placed on the pier. Cut youi posts to length, then secure them directly to the piers or toenail them to the blocks attached to the piers. Make sure the posts arc plumb and parallel to one another.

Girders must butt together over a post. When the end of a girder fits into a pocket in the foundation, you’ll have to shim up the girder to get the top surface level with the top of the sill. The shims used beneath girders will hear the full weight of the floor, so they must he cut carefully from pressure-treated stock. Cut uniformly thick shims instead of tapered ones and make them large enough to fit in
the bottom of the foundation pocket. Because of concretes ability to absorb moisture, code requires that the end of the girder he held about V: in. away from the hack of the pocket when cutting the girder to 111. If you’re not using pressure-treated stock for the girder, you can wrap the end of the girder with builder’s felt or sheet metal to give it some protection against moisture damage. Toenail the girders to the posts with either four 8d or three 16d nails. Now brace the posts and splice the girders by nailing the plywood gussets on both sides of the joint (see the illustration on p. 44).