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Renovation 4th Edition

Page 50

by Michael Litchfield


  The 4x14 Parallam beam sitting atop a 2x4 top plate (bottom photo below) is

  3. Get help to raise the beam one end at a

  much like the hidden beam discussed in “installing a Hidden beam” in the text. in

  time. If your cuts are accurate, you should be

  the old days, beams of this size would have been merely toenailed to top plates. So

  able to raise the beam between the severed joists

  the Simpson bC4 post cap now specified by engineers is quite an improvement. it’s

  and onto the top plate of one end wall and then

  the other. But, invariably, the beam will get hung

  simple to install and strong enough to resist uplift and lateral movement. note, too,

  up on something. Here, a chain fall is invaluable

  the 4x4 post directly under the beam—it’s part of the load path that goes all the

  because it allows you to raise and lower one end

  way down to the foundation.

  of the beam numerous times without killing your

  back or exhausting your crew.

  When the first end of the beam is up, nail

  cleats to both sides of the beam so it can’t slip

  back through the opening as you raise the other

  end. Raise and position the other end of the beam

  atop the other end wall and directly over the 4x4

  support post. Then use a metal connector such as

  a Simpson BC4 (see the top photo on p. 74) or an

  A-34 anchor (see the bottom photo on p. 72) to

  secure the beam to the top plates.

  4. Fine-tune the height of individual joists

  until their lower edges are flush to the bottom of

  the beam. This operation is easiest with one

  worker downstairs using a 2x4 to raise or lower

  the joist ends as a worker in the attic directs. As

  each joist is correctly positioned, attach it to the

  beam using joist hangers and the case-hardened

  nails supplied with the hangers. Before attaching

  joist hangers, however, use a power planer to cut

  a shallow slot into the underside of each joist to

  let in the hangers so they’re flush to the under-

  side of the joists. If there’s not much room to

  swing a hammer between joists, use a pneumatic

  palm nailer to drive the nails most of the way.

  Finally, along the edges of the beam slot, center

  and end-nail 2x4 backing between the joists for

  the finish-surface patches to come.

  For more details on this complex operation,

  see John Michael Davis’s article “Removing a

  Bearing Wall” in Fine Homebuilding issue #152.

  Structural Carpentry

  213

  9 Masonry

  Masonry needn’t always be straight

  lines. Here, clinker bricks, fieldstones,

  and tile playfully conceal a drab

  concrete retaining wall. (For more on

  this technique, see “Dressing Up a

  Concrete Wall” on p. 231.)

  masons began with a plastic medium (mud and

  Modern masonry employs a range of

  straw) that they shaped into hard and durable

  materials, including stone, brick, tile, concrete,

  building units of uniform size. Second, brick-

  and other minerals that become strong and dura-

  making is one of the earliest examples of mass

  ble when used in combination. The craft of

  production. Third, basic bricklaying tools, such

  masonry is ancient. The oldest surviving build-

  as trowels, were so skillfully designed that they’ve

  ings are stone, but stone is heavy and difficult to

  changed little in 5,000 years.

  work with. Brick, on the other hand, is less dura-

  ble than stone but lighter and easier to use. And

  clay, the basic component of brick, is found

  Terms, Tools, and Tips

  almost everywhere.

  Unless otherwise specified, mixes and methods in

  Technologically, the switch from stone to

  this chapter are appropriate for brickwork as well

  brick was a great leap in several respects. First,

  as concrete-block work. But most of this chapter

  214

  is about brick and poured concrete because

  concrete-block work is uncommon in renovation.

  TerMs

  Here’s a handful of mason’s lingo that’s frequently

  confused:

  Portland cement. The basic component of all

  modern masonry mixtures. When water is added

  to cement, it reacts chemically with it, giving off

  heat and causing the mix to harden, thus bond-

  ing together materials in contact with the mix.

  By varying the proportions of the basic ingredi-

  ents of a concrete mix, the renovator can alter

  the concrete’s setting time, strength, resistance to

  certain chemicals, and so on. Portland cement is

  A bricklayer’s tool kit (clockwise, from upper left): 4-ft. brass-bound level, tool bag, 6-ft. folding

  rule, statistical booklet (which covers estimating bricks and blocks, portland cement types, metric

  available in 94-lb. bags.

  conversion, and a glossary of masonry terms), 11-in. steel trowel, 51⁄2-in. pointing trowel, brick

  Masonry cement. Also called mortar cement, a

  hammer, two convex jointers, 4-in. brick set, box of line clips, and yellow stringline.

  mix of portland cement and lime. Exact propor-

  tions vary. The lime plasticizes the mix and

  Basic Masonry Tools

  makes it workable for a longer period. Once dry,

  the mix also is durable.

  Most of the tools listed in this section are hand

  Aggregate. Material added to a concrete mix.

  tools. Chapter 3 describes impact drills, rotary

  Fine aggregate is sand. Coarse aggregate is gravel. hammers, and other useful power tools. Important:

  Concrete aggregate is typically 3⁄

  Wear safety goggles and a respirator when strik-

  4-in. gravel, unless

  specifications call for pea gravel (3⁄

  ing, grinding, or cutting masonry. Errant chunks

  P R O T I P

  8-in. stone).

  of masonry can blind you, and masonry dust is

  Mortar. Used to lay brick, concrete block, stone,

  not stuff you want to breathe. Cement is also

  To determine

  and similar materials. As indicated in “Mortar

  how clean

  highly caustic, so heavy gloves are also essen-

  aggregate is, put about 2 in. in a

  Types” on p. 217, mortar is a mixture of masonry tial—preferably rubberized ones.

  quart jar and nearly fill the jar

  cement and sand or of portland cement, lime,

  with clean water. shake the jar.

  and sand. It’s typically available in 60-lb. bags.

  Trowels are indispensable masonry tools. If you

  have no other tool, a trowel can cut brick, scoop

  if there’s a layer of organic mat-

  Grout. A mix of portland cement and sand or of

  and throw mortar, tap masonry units into place,

  ter or dirt 1⁄8 in. or more floating

  masonry cement and sand. Mixed with enough

  and shape mortar joints. A good-quality trowel

  on the water, wash the entire

  water so it flows easily, grout is used to fill cracks

  load of aggregate carefully or get

&n
bsp; has a blade welded to the shank. Cheap trowels

  and similar defects. In tiling, grout is the

  a new load. Because seashore

  are merely spot welded. Bricklayer’s trowels tend

  cementitious mixture used to fill joints.

  sand is coated with salt and its

  to have blades that are 10 in. to 11 in. long.

  particles have been ground

  Concrete. A mixture of water, portland cement,

  Pointing trowels, which look the same, have

  smooth by water action, never

  sand, and gravel. Supported by forms until

  blades roughly 5 in. long; they’re used to shape

  use it as an aggregate.

  it hardens, concrete becomes a durable, mono-

  masonry joints. Margin trowels are square-bladed

  lithic mass.

  utility trowels used for various tasks.

  Reinforcement. The steel mesh or rods embed-

  ded in masonry materials (or masonry joints) to

  increase resistance to tensile, shear, and other

  The Point of IT All

  loads. In concrete, the term usually refers to steel

  rebar (reinforcement bar), which strengthens

  When you see the term pointing in masonry

  foundations against excessive lateral pressures

  texts, someone is doing something to mortar

  exerted by soil or water.

  joints—usually shaping or compressing them

  Admixtures. Mixtures added to vary the charac-

  so they weather better. Repointing or tuck-

  ter of masonry. They can add color, increase plas-

  pointing refers to adding (and shaping) new

  ticity, resist chemical action, extend curing time,

  mortar after old, weak mortar has been partially

  and allow work in adverse situations. Admixtures

  removed from a joint, usually with a tuck-

  are particularly important when ordering con-

  pointing chisel or a tuck-pointer’s grinder.

  crete because mixes may contain water reducers,

  curing retardants, accelerants, air entrainers, and

  a host of other materials that affect strength, cur-

  ing times, and workability.

  Masonry

  215

  Jointers (striking irons) compress and shape

  between existing courses or laying short runs,

  P R O T I P

  mortar joints, some of which are shown in

  such as the sides of a chimney.

  “Mortar Joints” on p. 221. The most common are

  When you’re chiseling or

  Mason’s levels are indispensable for leveling

  bullhorn jointers, shown in the bottom photo on

  grinding masonry materials,

  courses and assessing plumb. Generally 4 ft. to

  p. 223, and convex jointers, shown in photo 5 on

  sharp debris and dust fly every-

  6 ft. long, better-quality levels have an all-metal

  p. 220. The half-round, concave mortar joint they

  where. To protect your eyes, wear

  casing and replaceable vials. As you work, be

  wrap-around safety goggles with

  create sheds water well.

  sure to wipe wet concrete or mortar off a level

  impact-resistant lenses—safety

  Tuck-pointing trowels are narrow-bladed trow-

  before it hardens.

  glasses won’t stop missiles com-

  els (usually the width of a mortar joint, 3⁄8 in.)

  Brick tongs enable you to carry up to 10 bricks

  ing from the side. ideally, the

  used to repoint joints after old mortar has been

  goggles will fit tight to your face

  comfortably, as if they were in a suitcase.

  cut back. Because it packs and shapes mortar,

  and have air vents to keep them

  Concrete tools include floats (used to level con-

  this tool is both trowel and jointer and has more

  from fogging up.

  crete), finishing trowels (for smoothing surfaces),

  aliases than an FBI fugitive: tuck-pointing trowel, and edgers (short tools that contour edges). You’ll

  jointing tool, repointing trowel, striking slick,

  also need a strike-off board (usually a straight

  slicker jointer, slicker, and slick.

  2x4) for leveling freshly poured pads. Photos of

  Tuck-pointing chisels partially remove old mor-

  these tools in use appear in chapter 10.

  tar so joints can be repointed (compacted and

  Miscellaneous tools include safety goggles,

  shaped) to improve weatherability. Angle grind-

  knee pads, rubber gloves, rubber boots (concrete

  ers and pneumatic chisels also remove mortar.

  work), a flat bar, and a homemade mortarboard

  Mason’s hammers score and cut brick with the

  (a platform that holds mortar near the work)

  sharp end and are used to strike hand chisels

  made from scrap plywood. You’ll also need sheet

  with the other. The blunt end is also used to tap

  plastic to cover sand or cement, a concrete mixer

  brick down into mortar.

  or a mortar pan, a wheelbarrow, square-nose

  Brick sets have a cutting edge beveled on one

  shovels, buckets, a garden hose, and stiff-bristle

  side, so you can cut bricks precisely or dislodge

  brushes, among other things.

  deteriorated brick without damaging surround-

  ing ones.

  PreP TiPs

  Brick cutters are rentable levered tools that pre-

  The following tips will help your job go smoothly.

  cisely cut or “shave” brick, as you often must do

  Code. Check local building codes and get neces-

  when fitting firebricks to fill gaps in a firebox.

  sary permits.

  line blocks (or pins) secure a long, taut line to

  Water. Protect materials from rain. Because

  align masonry courses. They’re less important in

  water causes cement to set, sacks of portland or

  renovation masonry, where you’re often filling in

  mortar cement left on the ground—or on a seem-

  ingly dry concrete floor—will harden and become

  useless. If you store materials outdoors, elevate

  sacks on a pallet or scrap lumber and cover the

  pile with sheet plastic, weighting down the edges

  with rocks.

  Although bricks should be wetted before

  being laid, don’t leave them uncovered in a down-

  pour. They will absorb too much water, which

  can dilute the concrete and weaken the bond.

  (Concrete blocks, on the other hand, should be

  laid dry. Don’t wet them beforehand.)

  Sand and gravel are little affected by water,

  but if they absorb a lot of water, you’ll need to

  reduce the amount of water you add to a mortar

  or concrete mix. Damp sand won’t ball up when

  you squeeze a fistful; it contains about 1 qt. of

  water per cubic foot. Wet sand will ball up and

  will contain about 2 qt. of water per cubic foot.

  Dripping-wet sand oozes water when you squeeze

  it and will contain about 3 qt. of water per cubic

  foot. Of greater concern is the purity of these

  aggregates: Unload them onto an old sheet of

  Brick tongs let you carry bricks as if they were in a suitcase.

  216 chapter 9

  plywood or a heavy (6-mil) plastic tarp to keep
>
  them from being contaminated with soil or other

  organic matter.

  Two wythes

  zzzzzz Bricklaying Terms

  Weight. Masonry materials are heavy. To save

  labor, have materials delivered close to the work

  P R O T I P

  site. Likewise, have a mortarboard within 3 ft. of

  One wythe

  your work area and about waist high so you don’t

  Bags of cement

  need to bend over to scoop mortar. For this rea-

  sometimes

  get a “factory pack,” which

  son, scaffolding is a sensible investment if you

  makes the material seem mois-

  will be working higher than shoulder height.

  ture hardened even though it

  Divide materials into loads you can handle with-

  isn’t. raise the sack 2 ft. to 3 ft.

  out straining, and use ramps and wheelbarrows

  above a clean, dry floor and drop

  when possible. As you lift, get close to the object

  it squarely on its face. if that

  and lift with your knees, not your back.

  shock doesn’t loosen the sack, it

  Game plan. Before mixing mortar, complete pre-

  has absorbed moisture and

  paratory work, such as chiseling out old joints,

  should be discarded.

  Head joint

  removing old brick, and brushing dust off receiv-

  (mortar)

  ing surfaces.

  Bed joint (mortar)

  Curing. Give masonry time to cure. Because

  Course

  freezing compromises strength, plan your work

  (brick and mortar)

  so the mortar joints or new concrete will set

  before temperatures drop that low. Admixtures

  can extend the temperature range in which you

  can work, but exterior masonry work is easiest

  Mortar Types

  when the 24-hour temperature range is 40°F to

  80°F. On hot summer days, start early—prefera-

  Mortar is usually classified according to its strength and weatherability. The table

  bly on a shady side of the house—and follow the

  on p. 220 describes the correct proportions of ingredients for each.

  shade around as the day progresses. Cover fresh

   Type M has the highest compressive strength, at least 2,500 pounds per

  work with burlap sacks, dampened periodically,

  square inch (psi). This durable mix is recommended for load-bearing walls, masonry

  or with sheet plastic. The longer masonry stays

  below grade, and masonry not reinforced with steel.

  moist, the stronger it cures.

   Type S has a relatively high compressive strength (1,800 psi) and the best

 

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