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y neighbor saworried tonetub drain in mroom is backin
All the time? I asked.No, just when we flush the I knew
instantly this job wo
more than just snaking out An hour and several bucket
lounspeakable stench later, mycions were confirmed. A rougthat had
been left at one of thin the PVC drainpipe had snabit of paper,
which over time hcalated into a full-blown, nasThe only way to fix
the prproperly was to replace the
fittings. Prepping the pipe one place a PVC installation wrong.
The first step is chooscorrect fittings (sidebar facingHere are
some tips to keep flowing smoothly after that.
Cut PVC pipe as squareas possible
One of the joys of PVC pipe is easy to cut. Just about any
sawfine. If I have the room and Iting a lot of pipe, I set up a
ch
which gives me a square cut wa lot of burrs. While a reciprosaw
makes a quick cut, extra cto be taken to keep it squarrule of
thumb, I try to keewithin 18 in. of square, whicpecially critical
for smaller pi
A PVC saw also makes a goand its wide blade is easier t
BY ED CUNHA
Its easy to work with, but youve stillgot to choose the right
fittings andfollow some basic rules
Nail plate
Hangerstrap
BUSHING
T-Y FITTING
CLEANOUT
BEND
TRAP
Y FITTING
Buyingplasticpipe
PVC pipe comes in different thicknesses, or schedules. The
thinnest,
schedule 20, is primarily for foundation drainage and
ground-waterremoval. Schedule 40 is best for domestic piping
systems and comes
as foam-core (also called cellular-core) or solid-wall pipe.
Foam core is
lighter and more flexible, but both types can be used for drain,
waste,
and vent piping. In some pressurized systems, though, only
solid-wall
schedule 40 can be used. The thickest, strongest PVC is schedule
80.
Schedule 40 ABS is used the same way as schedule 40 PVC.
Lighter
and more flexible than foam core, ABS is black and can warp in
the sun.
66 FINE HOMEBUILDING
PVC PipeA Primer on
M
Cellularfoam-corePVC pipe
Solid-corePVC pipe
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square (photo top left). These saws cos$15 and have replaceable
blades. In ayou also can use a hacksaw. Its smalminimize the amount
of burr left pipe, but a hacksaw is the toughest keep cutting
square.
These options are great when therefor a saw, but what about in
tight quarwhen the pipe that needs cutting is c
other pipes or wires? In these cases, I pa cable saw (photo top
right), whiclength of thin wire cable with plastic hat both ends.
Just slip one of the haround the PVC pipe and pull the caband forth
perpendicular to the pipsmooth, easy strokes. The friction of ble
on the pipe literally melts throuPVC. Believe it or not, you can do
th
Two ways to cutPVC pipe. A PVC-pipe saw has fineteeth that
leaveminimal rough-ness along theedges and a wideblade thats easyto
keep square.A cable saw isjust a length ofcable with twohandles,
but itcan cut throughany size PVC pipewith almost
zeroclearance.
No rough edges, please. CuttingPVC pipe with any type of
sawleaves burrs along the edges. Re-moving the burr from the
outsideedge (photo left) allows the pipeto fit properly in the
fitting. Re-moving the inside burr (photoright) allows waste to
runsmoothly through the pipe.
Clean and glue.Dry-fit, make indexmarks, and disassem-ble the
fittings before ap-plying cleaner/primer to bothpieces. Then apply
a thincoat of PVC glue in the fit-tings hub and a generouslayer on
the pipe.
PVC cleaner andglue cans tapedtogether
Fit and twist. Next, push thetings together and twist untilindex
marks line up.
Fill gaps. When the connectisolid, wipe the top of the huba
light layer of glue to fill anymaining gaps.
68 FINE HOMEBUILDING
CUTTING AND DEBURRING PVC PIPE
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DECEMBER 2003/JANUARY 200
thing with a length of masons twine, but ittakes a lot
longer.
Smooth the edges of the pipe
Cutting PVC pipe always creates burrs onboth the inside and
outside edges of the pipe.As my neighbor can attest, removing
burrsfrom the inside of the pipe is absolutely nec-essary to keep
waste flowing smoothly to its
final destination. Burrs on the outside of thepipe can prevent a
proper fit and glue joint.
After making any cut into PVC pipe, I firstdrag a utility-knife
blade around the outsideedges to scrape off the burrs (photos
centerleft, facing page). Next, I cut the burr fromthe inside edge
of the pipe with the knife, al-most like peeling an apple. I always
run myfingers around both edges to feel for anywayward burrs I
might have missed. Theslightest burr can snag hair or other
debris,plugging up the pipe in no time.
Cleaning the pipe is as importantas gluing it
When connecting the fittings and pipe in aPVC line, first align
the fittings with thepipe to ensure the proper pitch and angle.Then
mark a straight line from the hub onthe fitting onto the next
fitting or the pipe.I usually use a felt-tipped marker becauseits
easy to see and doesnt rub off easily.
Clean or prime the glue-joint area beforegluing (center photo,
facing page). Lazyplumbers might try to get away with usingglue
alone, but manufacturers make a two-
part system for a reason. The primer notonly cleans the PVC, but
it also starts tomelt the PVC slightly. The glue then bondsthe
softened pipe and fitting together.
To clean the pipe and fittings, I run thedauber attached to the
lid of the primer (or a34-in. paintbrush if no dauber is
provided)around the pipe and fitting two or three timesin each
direction. Dont try to test-fit afteryouve cleaned and primed the
pieces, ortheyll stick together.
Next, I apply a light layer of glue insidethe fitting and a
generous amount on the
pipe. Again, I run the dauber around twoor three times to ensure
an even spread ofglue. I wear disposable gloves and never usea rag
to apply cleaner or glue.
Twist and hold for a tight joint
After applying the glue, I push the fittingonto the pipe,
holding both pieces tightlywith the alignment marks about 1 in.
apart.
I then twist the fitting and the pipe until themarks line up
(photo center right, facingpage). After holding the joint together
forabout 30 seconds or until it is completelysolid, I give the
joint a quick wipe all aroundwith the glue dauber to fill any air
pocketsI might have missed (photo bottom right,facing page).
PVC might not be the only typeof pipe in your system
I routinely come across situations wherePVC has to be tied into
other types ofplumbing, in both new construction andrenovation. In
new construction, cast ironis used to keep noise down where
plumbingmight run through the walls of living spaces.
Here on Cape Cod, many folks want cop-per for the end of the
vent that sticksthrough the roof. In these cases, PVC isused for
all the complicated fittings becauseit is easy to work with and
inexpensive. The
PVC then is tied into the metal (top photo).Whether PVC is
connecting to copper,
cast iron, or galvanized steel, its extremelyimportant to start
with a good, clean cut.Use a pipe cutter if you have the room
tospin it, or use a reciprocating saw with afresh metal-cutting
blade. A file used onthe inside edge of the metal pipe smooths
itbefore you make the connection. For the ac-tual connection, I
like to use a no-hub clamp(center photo). Stronger than a
one-piecerubber clamp, a no-hub clamp has stainless-steel bands
with pipe clamps and a rubber
sleeve that varies in thickness to fit the ma-terials being
joined.
Ive had only one occasion where I had tojoin PVC to a dissimilar
plastic. I was con-necting the pipe to the septic system in
amodular home that had been plumbed withABS. In this case, I simply
applied some all-purpose glue designed to be used with bothtypes of
plastic. One word of caution: Makesure you use the appropriate
primer foreach type of pipe. Just as all glues are notcompatible,
your PVC primer might notwork on ABS.
If there is any doubt about the glue orprimer, you can make a
tight fit betweenPVC and ABS with a male and femalethreaded
adapter. Use the appropriate glueto fasten the adapter onto each
pipe, andthen thread them together.
Ed Cunha lives in and works out of Brew-
ster, Mass. Photos by Roe A. Osborn.
A hole drilldrainpipe cweaken theso special rforcement pmay be
reqThese platethe added of protectinpipe from wdrywall
nailscrews.
Dont likelooks of avent pipethat expeshake rooPVC up tofinal
vertirun, and ttie in a shpiece of c
COPPER ROOF VENTS
CAST IRON FOR SILENCE
STUD REINFORCEMENT
Use it in the walls of livingspaces, and use less-expensive PVC
to make allthe complicated connectionsat the fixtures. Special
no-hubclamps tightened with aratchet wrench (right)
make a tight, leak-proofconnection.
