Renovation 4th Edition
Page 73
even lighting rather than “pools” of light.
In retrofit installations, the supply cable to the
Junction
Housing
box
recessed lighting unit typically comes from an
or can
existing ceiling box or nearby switch box. The
Mounting clips
supply cable feeds to an integral junction box on
extend, rest on
the fixture. Finding the nearest power source and
ceiling
Armored cable
fishing the wires to the fixture are always an
adventure if there’s not accessible space above. If
the recessed fixture is a low-voltage unit, such as
the one shown here, it will come with a trans-
Finish ceiling
former, which reduces the 120v current of the
Can lip
supply cable.
Cutting a ceiling hole for a recessed fixture.
Baffle or
There’s no absolute on where to place a recessed
trim piece
light, but in a small space, such as a shower alcove,
a fixture centered in one direction or another will
look best. In addition, you may want to use a
stud finder to avoid hitting ceiling joists above.
310 Chapter 11
1. There are no absolutes in placing
lights, but a single recessed fixture
centered in one direction or another
usually looks good.
2. Before you commit to a location, 3. As you drill, keep the axis of the
4. If the can fits too snugly in the
drill a small exploratory hole to make
bit vertical and the sawblade square
hole, use a jab saw to enlarge the hole
sure there’s room for the recessed
to the ceiling. Wear safety glasses.
slightly.
can—i.e., that there’s not a ceiling
joist, pipe, duct, or wire in the way.
5. Testfit the fixture. The gray box
is an integral junction box that will
house all wire connections.
Drill a pilot hole to see what’s above and to
make sure there’s room for the can. Make the
hole small because if there’s an obstruction above
it, you’ll need to patch it. After drilling the hole,
you can insert a 4-in. piece of bent wire and
rotate it to see if it hits a ceiling joist.
The small pilot hole will keep the point of a
6. After running the cable through the hole you cut in
hole-saw blade from drifting. Keep the drill verti-
the ceiling, remove a knockout in the fixture’s junction
cal and the circle of the sawblade parallel to the
box. The cable is not energized at this stage.
7. Strip sheathing from the cable,
feed it into the box knockout, clamp
the cable, and splice fixture wires to
the supply wires.
8. Whatever the device, always
9. When you have spliced all wires, 10. Close the junction box cover.
connect ground wires first.
tuck them carefully into the fixture
Make sure no wires are pinched
junction box.
between the cover and box.
electrical Wiring
311
ceiling. There are special carbide hole saws for
connect the secondary wires that run from the
P r O t I P
drilling through plaster. A bimetal hole saw will
transformer to the socket. (At the transformer,
also cut through drywall, but plaster will very
the current is reduced from 120v to 12v, so polar-
recessed ceiling lights that
quickly dull the saw in the process. Wear goggles.
ity is no longer an issue.) There also are three
are iC-rated can be covered with
If the hole saw is the right size for the can, you unconnected fixture leads in the box to which
insulation. non-iC-rated cannot.
won’t need to enlarge it. But for the light shown
you’ll splice the supply wires.
see pp. 393–394 for more infor-
here, the saw was a shade too small, so the install-
Using wire connectors, connect the incoming
mation.
er used a jab saw to enlarge the hole slightly. In a
ground wire to the green fixture lead, the incom-
pinch, you can also use just a jab saw.
ing neutral to the white lead, and the hot wire to
Test-fit the unit. Although you want the can to the black fixture lead.
fit snugly, the unit’s junction box and transformer
Tuck the spliced wire groups into the fixture
also need to fit through. Below, the black box
junction box. At the right of photos 8, 9, and 10
about to enter the hole is the transformer.
on p. 311 is a piece of threaded rod that can be
adjusted to support the transformer at the cor-
Wiring a recessed fixture. To wire a recessed
rect height. Snap the junction box cover closed.
fixture, remove a Romex knockout from the
As with other outlet boxes, code determines the
unit’s integral junction box. Inside the knockout,
number of wires you can splice in a fixture junc-
there is a spring-loaded, strain-relief clamp that
tion box, based on the cubic inches in the box.
will grip the incoming cable, so you don’t need to
insert a Romex connector. Run a length of
securing the can. Once the recessed lighting
(unconnected) Romex cable from the nearest
fixture has been wired, push the fixture into the
P r O t I P
power source, and feed it into the knockout just
hole, being careful not to bind the Romex cable
removed. Of course, the cable must not be ener-
as you do so. If the fit is snug, use the side of
When installing halogen
gized when you are working on it. (To wire the
your fist to seat the lip of the fixture flush to
lamps, the pros apply a tiny dab
box with AC or MC cable, remove one of the cir-
the ceiling.
of antioxidant paste to the lamp
cular 1⁄2-in. knockouts and insert an appropriate
Use a screwdriver to push up the spring-loaded
pins before seating them in a fix-
connector.)
clips that pivot and press against the back of the
ture socket to prevent oxidation.
Inside the fixture’s junction box will be two
drywall and hold the fixture snugly in place. To
sets of wires that were spliced at the factory. They remove the fixture later, pop the clips out.
12. The lip of the can should sit
13. Use a screwdriver to push up the 14. Insert the bulb with a
flush to the ceiling; use your fist as
springloaded clips that pivot and press gentle pressure until all pins
needed to seat it.
against the back face of the drywall to
seat. This is a lowvoltage
hold the fixture snugly in place.
halogen bulb. Wear gloves or
hold the bulb by the rim to
avoid getting contaminants on
the bulb.
11. feed the cable and the nowwired fixture into the hole.
15. Install the trim assembly. The
black ring in this assembly
is a
moistureproof gasket.
312 Chapter 11
Insert the bulb (the fixture shown uses an
MR-16 bi-pin halogen bulb) into the socket. Note
that the installer is gripping the lamp’s reflector,
not the bulb itself. The lamp pins should seat
securely. Install the trim piece—this one has a
watertight gasket. Snap in the lamp and socket,
and push the assembly up into the can. The three
arms on the side of the assembly will grip the
inside of the can.
ConverTing an inCandesCenT
After turning off the power to the
fixTure To an led
fixture and testing to be sure, remove
the trim plate and screw out the
It probably takes more time to write about retro-
incandescent bulb. The recessed can
fitting an LED fixture than to do it. Turn off the
stays put.
power to the fixture, and use a voltage tester to
be sure it’s off. Remove the fixture’s cover plate,
and unscrew the incandescent bulb. Screw the
threaded adapter into the fixture socket. The
other end of the adapter is an orange plastic,
This simple kit can convert an incandescent ceiling fixture
quick-disconnect connector that snaps to a
into an energysaving lED fixture. Clockwise from lower
right: a screwin adaptor, castaluminum trim plate and
matching connector on the LED housing. Snap
lens, lamp housing, and heat sink.
the two cast-aluminum pieces of the housing and
cover together, then screw the cover to the
recessed can with three screws.
Snap the housing and trim plate together, screw in the
Similar retrofit kits fit either 3-in. or 4-in.
adapter, connect the (orange) quickdisconnect
connector, and slide the assembly into the recessed can.
cans. Although all come with some means of dis-
final mounting details will vary, but clips or universal
sipating excess heat, the model shown at right,
mounting screws will hold the assembly to the can.
from DMF Lighting®, has a heat sink. The 650-
lumen lamp is dimmable to 5% and is as bright
as a 50-watt incandescent; it consumes less
than 12 watts.
light fixture at end of Cable run
Portfolio of Wiring
zzzzzz
Grounding screw
Schematics
Metal box
The diagrams in this section show a few of the
more common circuit wiring that you’re likely
to need when wiring receptacles, fixtures,
and switches. (See also the schematics on
pp. 300–305.) Unless otherwise noted, assume
that incoming cable (from the power source) and
all others are two-wire cable with ground, such
as 14/2 w/grd or 12/2 w/grd (#14 wire shall be
protected by no larger than a 15-amp breaker or
Nonmetallic box
fuses; #12 wire shall be protected by no larger
Ground
than a 20-amp breakers).
All metal boxes must be grounded. The boxes
in the wiring diagrams are nonmetallic (plastic)
unless otherwise specified and so aren’t grounded
with a screw in the box. In sheathed cables,
Neutral
ground wires are bare copper. Black and red
wires indicate hot conductors. (Some devices
Incoming power
with multiple wire leads also use blue hot wires.)
White wires indicate neutral conductors, unless
taped black to indicate that the wire is being used
as a hot conductor in a switch leg.
Hot
electrical Wiring
313
a simple switch with a “switch loop”: the Modern Method
zzzzzz
Ground
Incoming
Metal box
power
Grounding
screw
Three-wire
cable
Hot
Neutral
Ground
Nonmetallic
box
Neutral
available for
Hot wires
electronic
switch
Close-up: Three-Way switch
zzzzzz
Traveler wires attach
to brass screws
Three-way switches control a
fixture from two locations. Each
switch has two brass screws and a
Common (COM)
black screw (common terminal).
terminal
The hot wire from the source
attaches to the common terminal
of the first switch. Traveler wires
between the switches attach to
the brass screws. Finally, a wire
runs from the common terminal of
the second switch to the hot lead
of the fixture.
314 Chapter 11
Three-Way switches, light fixture between
Travelers
zzzzzz
Metal box
3-wire cable
3-wire cable
Neutral
Grounding screw
Incoming power
Hot
(2-wire cable)
White wire
Ground
taped black
Common
Common
(COM)
(COM)
terminal
terminal
Neutral
Travelers
Travelers
Ground screw
Ground screw
In this setup, two three-way switches control a light fixture placed between
them. Run 3-wire cables between each switch and fixture. Whenever you use a
white wire as a switch leg, tape it black to indicate that it’s hot.
Three-Way switches: light fixture at start of Cable run
zzzzzz
Incoming power
(2-wire cable)
Grounding screw in metal box
Here, incoming power enters
through the fixture box.
2-wire cable
Hot
Hot white wire
3-wire cable
taped black
Neutral
Hot white wire
taped black
Common
Switch leg
(COM)
terminal
Common
(COM)
Hot white wire
terminal
taped black
Travelers
Travelers
electrical Wiring
315
12 Plumbing
Consult local plumbing codes before
Builders have benefited greatly from beginning a project. Codes protect your health
the standardization of building materials, and
and that of your neighbors. They spell out
nowhere is this truer than in plumbing. While
when you need permits, what materials you
plumbers once fashioned waste systems from cast may use, and at what stages the work must be
iron, oakum, and melted lead, today one needs lit- inspected. There is no national code, so most
tle more than plastic pipe and solvent-based
local building departments often follow the
cement. Better technology enables more people to Uniform Plumbing Code (UPC) or the
understand, repair, and install plumbing.
/> International Residential Code (IRC). Get a
Would-be plumbers should do two things:
copy of local plumbing codes from your
Learn the vocabulary. Some people feel
building department.
intimidated by the plethora of plumbing terms,
Recommended further reading is Rex
especially fitting names. But there’s actually a
Caudwell’s Plumbing Complete (The Taunton
logic to all those names, once you learn what a
Press, 2009).
part does and why it is shaped as it is. Besides,
you’ll get better service from plumbing-supply
clerks if you can speak their language.
An Overview of
Plumbing Systems
Mother Nature knows a thing or two
A plumbing system is a loop of sorts, created by
about plumbing. The larger midrib of
this leaf is a naturally occurring
supply (or delivery) pipes that carry potable
trunk line, with smaller veins
water to the house and its fixtures and by drain-
branching off to supply the leaf.
age, waste, and venting (DWV) pipes that carry
wastewater, effluvia, and sewer gases away from
the fixtures—sinks, toilets, lavatories, and wash-
ing machines.
These two systems within a system are quite
different from each other. DWV pipes are larger
and must slope downward so waste can fall freely
(by gravity) and sewage gases can rise through
vents. Consequently, large DWV pipes can be diffi-
cult to route through framing. By contrast, smaller
water-supply pipes are easy to run through studs
and joists, and they deliver water under pressure,
so there’s no need to slope them.
The waTer supply
The pipe that delivers water to a house (from a
city water main or an individual well) is called
316
Need a permit?
zzzzzz The water-supply system
Local plumbing codes vary greatly. In general,
you don’t need a permit if you replace a fixture,
such as a sink, toilet, or washing machine, with-
out changing existing pipes. However, if you
want to add new fixtures or move existing ones,
you’ll need a permit because you’ll need to
change pipes.
Replacing a water heater also requires a
permit—even if you connect to existing pipes.
P R O T I P
Here, the issue is safety: Inspectors want to
make sure that gas- and oil-fired water heaters
are properly vented and that electric heaters
If you’re new to plumbing and
need help, learn the lingo and
are correctly wired. They’ll also check that