Old House Re-Roofing
- Installing Shingles
Bruce W. Maki,
Prior to shingling we spent several days tearing off the old
shingles and adding an additional layer of wood sheathing. This can
be seen in Part 1.
Starting With A Clean Slate:
We completed the OSB on the larger roof face.
Next the drip edge was installed, also running up the side
edge (known as the "rake") as far as we could reach.
The lowest part was covered with Ice and Water
Shield, and the felt was fastened over top.
At this point the roof was "dried in", so it would be
well protected from rain. This stage is the most important goal in
roofing, usually. Often this point can be reached in one day, but
with all the extra work of laying the new OSB, this milestone took
us almost three days.
I didn't take enough photographs during the first phase to fully
describe the process of roofing. So I shot some more photos of the
second phase, which appear later.
I installed this self-adhesive shingle starter
With conventional three-tab shingles most roofers simply
cut the tabs off some shingles. Some people just install a row
of shingles top end down, but that's kinda lame.
I tried to make the starter strip overhang the
drip edge by about 1/8", but it didn't work that way.
This stuff is like trying to apply a 20 foot long sticker, and
once there is a slight mis-alignment it's hard to fix. So I
just cut the material back.
Now, y'all don't have to be as dumb as me
when you use this product.
That shiny black line... that is the tack strip, and
its job is to stick to the shingles above it. The tack strip
is supposed to be at the bottom, not at the top!
Later, to correct my absent-minded mistake, I went back and
dabbed some tar between this piece and the first row of
Where the lower roof met the wall, I installed a
piece of step flashing over the starter strip. Every row of
shingles must have a step flashing at the wall. It is
installed on top of the concealed portion of the
shingle. The idea is that any water that gets around the end
of the shingle will be forced on top of the next shingle
What you cannot do is simply run a one long angled
flashing up the corner before shingling. Water will eventually get
under the shingles and possibly rot the roof sheathing.
When the first row of shingles was installed, I
nailed another step flashing in the corner.
Note that these are nailed to the roof, not the wall.
Also note that before installing the shingles I did the following
treatment to the small section of wall:
- Applied a 12" wide strip of Ice and Water Shield to the
- Applied a layer of 15# asphalt felt (tar paper) to the exposed
- Fastened 1/2" thick polyisocyanurate foam to the wall,
using ring-shank plastic cap nails.
- Taped the joints with special tape for housewrap.
After three or four rows of shingles were
installed I nailed the roof jacks in place and laid 2x10
planks on them.
Note the thin vertical strips of wood on the upper roof. I
nailed some scraps of OSB to the roof to hold the tar paper in
place. This worked very well and was faster than nailing the
The same thing from a different angle. Note how
the step flashings go all the way up. Once I reached this
point I had to shift gears and install shingles on the other
face of the roof, because of the way I decided to approach the
I had to go away for a day, and when I came back
I noticed that the Ice and Water Shield appeared to have
shrunk and was not laying in the valley properly. This
was quite a problem, I figured, because if somebody stepped on
the valley (very likely) their foot would probably tear the
shingles and cause a leak.
Before continuing, I called W.R. Grace's toll-free technical
assistance line (1-800-444-6459 option 3, or www.graceconstruction.com)
and found out the cause. The representative said that if Ice and
Water Shield was installed in high temperatures then it could easily
be stretched. It was about 95 degrees when we installed these
pieces, and the roof faces south. Not exactly a cool environment.
They instructed me to slit the first piece and install another layer
on top, being extra careful not to stretch it. It worked fine after
Their help reminded me of why I only use W.R. Grace brand of Ice
and Water Shield. Grace invented a heavier version of this material
about 35 years ago. The original name was "Bituthene",
which is pronounced just like "bitch-a-thane", and that
has a whole set of marketing consequences, I guess. The heavier
version is still called Bituthene, and is meant for waterproofing
basements. The name of this roofing underlayment was
changed to Vycor a few years back, which confused people, then they
changed the name to simply Grace Ice and Water Shield. Well anyways,
their patent expired a few years ago and many companies now make
similar products. Grace has years of expertise making this
bituminous rubberized asphalt shingle underlayment, and their
product costs a trivial amount more than their competitor's
products. So why take chances? I've used other products and they
didn't stick as well. (And no, I'm not being paid to promote W.R.
I made decent progress along the small face of
the roof. I did this amount in about an hour. The air
Note how the shingles run past the valley a
ways. This is for the closed valley method.
There are some rules to adhere to:
- No nails within 6 inches of the center of the valley.
- Keep the ends of the shingles 10 to 12" away from
the center of the valley.
This last rule means that the first shingle in each new row
must be chosen carefully to ensure that no ends of any shingles
will land in that "forbidden zone".
Within a few hours I had the entire face
shingled. Besides the first set, I only needed to install one
additional set of roof jacks, thanks to our custom-made ladder
As I approached the chimney I decided to procrastinate,
and deal with the details later. This worked alright, although
there were a few small leaks around the chimney during some
But I did apply some pieces of 6" wide Ice and Water
Shield to the junction of the brick and the roof.. It stuck to
the brick quite well.
I later installed some snazzy flashing around the chimney,
including the elusive and rarely-seen counter-flashing, which makes
a truly impenetrable barrier to water.
I shingled up to the ridge and folded the shingles over. The
folded-over part overlapped the old shingles on the other side,
thus preventing leaks.
Working under the lightning rod was no problem, I just
lifted it up. Later I fastened the rod brackets with roofing
Once the small face was done I turned to the
larger face. Again I only needed two rows of roof jacks and
planks, because of the ladders.
At this stage some planning needs to take place. At several
points across the face I measured the distance from the peak down to
the most recent row of shingles. Inevitably the shingles are not
perfectly parallel to the peak. This won't be visible when there is
5 feet of roof remaining, but if corrective actions are not taken,
the final row of shingles will appear to be tapered, which is just
poor practice and looks unprofessional.
My approach was to measure down from the peak and make marks on
the felt with a carpenter's crayon (a yellow Crayola will work) at
10 inch intervals (i.e. 10, 20, 30, 40 inches down from the peak). I
did this at both ends of the roof. Then I snapped chalk lines
between corresponding marks. This set of parallel lines made it easy
to lay out the shingles in straight rows. I would simply judge by
eye how close the top of the shingles were to the next line above.
There were one or two rows of shingles whose exposure was tapered,
but in the middle of the roof this cannot be seen. And architectural
shingles help to hide flaws in layout.
Before I laid shingles into the valley I snapped a chalk line
along the center line.
As the row reached the valley, I would set the last shingle
in place and use a pair of tin snips to mark the cut. There
are plenty of details about cutting valley shingles later
in this article.
The last row has to be high enough that the
ridge shingles (which are single tabs cut from 3-tab shingles)
will cover the nails. This means that the nails have to be
less than about 5 inches from the peak. If not, another row of
shingles would have to be installed.
Notes From Phase 2:
A Little Practice Makes For Rapid Progress:
In the second phase, I began installing shingles
while completing the new OSB sheathing.
When I got to the last row of OSB sheathing, I
had to remove the scaffolding and move the ladders below the
roof edge. I simply put two ladder jacks on the
heavy-duty ladders and lowered the 12' long 2x10 plank onto the
jacks. Doing this rigging by myself was awkward.
At this point the roof was "dried in" and ready
In phase 1 there was a porch roof to stand on, so this
ladder juggling was not necessary.
I installed the shingle starter strip and the
first few rows of shingles. After 3 rows of shingles I
installed the red steel roof jacks, which hold planks up to
I set the first short section of plank on the
jacks. I also tied my hoisting rope to the plank.
Each roof jack has a hole so a nail can be driven into the
plank, which keeps the boards from shifting.
Once the roof jacks and scaffold planks were
installed, I moved the ladders so they leaned on the scaffold.
I wanted to avoid leaning the ladders against the aluminum
drip edge, because I know from past experience that drip edge
gets bent out of shape and the shingles get damaged from the
weight of a ladder.
Once I reached this point I plugged in the pneumatic
roofing nailer and went to town.
After a couple of hours of working by myself, I
had about half of the larger face shingled.
Once I had reached the valley I shifted my
attention to the higher, smaller face. Those shingles will be
run long, past the valley.
I put a small piece of starter strip at the lowest edge of
the valley (that little black piece). I could have used a
shingle for this.
I commenced shingling on the small face, letting
the shingles run past the valley.
During this process I installed a second tier of roof jacks
and scaffold planks. I located these so I could reach them
easily from my 6' home-made ladder stairs.
It took me less than two days to reach this point.
To mark the centerline of the valley, I snapped
a blue chalk line. I had to drive a nail at the top end
(beyond the shingles, of course) because I had no helpers.
This line will be used as a cutting guide for the shingles
on the other face.
Blue chalk will wash off in the rain. I've heard that red
chalk will not wash off.
To crop the valley shingles, I set the full
shingle in place and used tin snips to nip the
top and bottom edges where they intersected the blue valley
Then I flopped the shingle onto the scaffold, face down. I
curled up the shingle at the nips, placed a steel ruler
against the curls, and cut the shingle with a utility knife.
This method was quick and the cuts were nearly perfect.
Fitting Shingles Into The Valley:
As each row approached the valley, I would lay a shingle in
place (1) and examine how big the final shingle would be. The
cut edge of the valley is at arrow 2. In this case, the final
shingle would be too short, because if I kept the nails 6
inches from the valley centerline this fractional shingle
would only be anchored at one end.
My solution for the above case was to use a shorter (i.e.
partial) shingle for number 1, thus leaving me room for a larger
final shingle. But... as mentioned earlier, care must be taken so
the partial shingle's ends are not too close to the gaps below it.
In cases like this I typically used a half-shingle in place of a
full shingle. (You cannot do this with 3-tab shingles.)
The proper practice is to be careful when choosing the length
of the first shingle in the row, to ensure that there would be
no gaps too close to the valley. The usual method of starting rows
(which works fine on a simple rectangular roof) is to begin a row
with a full shingle, then a 3/4 shingle, 1/2, 1/4, and back to a
full. But when shingling into a valley it's sometime necessary to
use a completely different pattern for the initial shingles, as long
as the gaps are staggered by at least 6 inches.
|After everything was done, I lifted up each cut
shingle at the valley and applied a bead of roofing cement
(tar) to seal the edges. This should discourage water from
Tying The Two Phases Together: Shingling The
Details: Ridge Meets Face
The first phase can be seen in the rear.
This was tricky, because the shingles on the second phase
did not line up perfectly with the shingles on the first
phase. No matter how careful you are, this is a problem with
roof faces that start out divided (i.e. at the bottom) and
join higher up.
It might help to measure up from the drip edge or down from the
peak, but there's no guarantee that the house structure is square
Also, that red roof jack was left there for a reason... it will
provide access when I do the flashing around the chimney.
I adjusted the exposure on some rows of shingles
to get the two faces to line up as close as possible. The
shingle I'm holding is important because it will cover the
intersection of the ridge.
The ridge "runs into" the other face of the roof,
whose ridge is about 2 feet higher.
Looking at these pictures is like staring
The red arrow points to the ridge. I'm holding up the
shingle above (on the higher face). This shingle was not
nailed normally, at first. I nailed it at the top so I
could lift it up and work underneath. Later I nailed it
To make the ridge blend in, I made a slit in the shingle
that intersected with the ridge. Without this cut, the shingle
would not lay flat.
I suppose I could have made a V-shaped cut instead.
The last row of shingles just barely extended
past the peak. I later trimmed back this slight overhang,
because it got in the way.
This is a crucial test. I placed a ridge
cap shingle in place to see if it would cover the nails of the
row below. It wouldn't. (The other side of the roof was fine.)
This meant that I had to install one more row of shingles.
I laid another row of shingles (1), which was
folded over the peak.
As I moved along, I nailed down the ridge cap shingles (2).
The ridge cap shingles are not the same
as the rest. These are cut from plain ordinary 3-tab asphalt
Some people use a utility knife to cut these, I used a pair
of tin snips. If the weather was warmer (i.e. above 60 degrees
F) a knife might have been easier.
Note how the buried part of the shingle is cut with a
taper. Simply cutting the shingles into 3 separate tabs
doesn't work as well, because the cut edges would be visible.
Ridge cap shingles are bent over the peak of the
roof and nailed in two places along the usual nailing strip. I
kept the nails about 1 inch above the edges.
Shingling the ridge takes very little time. I did this 25 foot
long stretch in about 45 minutes, and I took my sweet time too.
The final ridge shingle had to be split so it
would lay flat against the roof.
That final cap shingle is covered by a shingle
on the roof face above it. That's the shingle that I slit
I applied a liberal dab of roofing tar under all
of the shingles around this critical junction.
If I had any doubts about this area leaking, I would apply
a dab of black silicone to the outside parts. Roofing
cement (tar) will only last about one year if exposed to
sunlight, and then it becomes brittle. Silicone will last
about 50 years, a lot longer than these shingles.
The other ridges will have to wait until the
last two quadrants are completed.
When I re-installed the brackets for the
lightning rod, I applied a dab of black silicone under the
bracket and the nail heads (red arrow).
This is a photo of the first phase, after we:
This picture was taken before the second phase was begun.
This is what it used to look like. I'd say it's
There were 3 different colors/styles of shingles on this
house before we replaced the roof.
Some thoughts on architectural multi-layer shingles.
This newer type of shingle has really caught on lately,
especially here in Northern Michigan where there are a lot of
high-end vacation and retirement homes being built. But I've also
been noticing these shingles on a lot of ordinary houses, too.
There are some benefits to architectural shingles:
- There are no tabs to break off in a strong wind.
- The random appearance makes mistakes easier to hide.
- You don't have to be concerned with the proper staggered tab
alignment that is necessary with 3-tab shingles. Standard 3-tab
shingles are 36" long, so each tab is 12" long. Each
successive row of shingles has to be placed either 6" or
18" to the left or the right, but never 12" or
- With architectural shingles some common-sense rules apply:
keep the ends of the shingles (on adjacent rows) at least 6"
apart. But you can separate the joints by any amount greater
than 6". The instructions for these shingles (by IKO) say to cut
10", 20" and 30" off shingles to get the fractional shingles for
the beginning of each row. Since these shingles are around 41"
long, the cut shingles are essentially 1/4, 1/2, and 3/4
shingles. There is no reason why you couldn't use alternating
full and half shingles at the beginning of the rows.
- A partial shingle can be used almost anywhere (if you're
careful), so there can be less waste. It occurred to me that a
person could shingle an entire roof with scraps of
architectural shingles. It would be similar to wood shingles,
which are often only a few inches wide. This odd idea should
work as long as the gaps were kept apart by the required 6
inches. Now that would be a waste of time for most people, but
leftover shingles could be employed for a small shed, for
example, even using different color shingles scattered randomly.
- Based on the two roofs I have done using architectural
shingles, I would say that they are easier to work with.
- The one major drawback (besides the higher cost) is the lack
of flexibility of architectural shingles. Curving the shingles
in the valley takes a bit more patience, especially when the
shingles are cold.
I was tempted to get a couple of quotes from local roofing
contractors, just to see how much money we'd be saving. But I don't
believe in pestering contractors for information when I fully intend
to do the work myself.
But from my experience, I believe it would cost between $8,000
and $12,000 to have this house re-shingled by a roofing contractor.
Although at his writing we have only finished half of the roof, I
can make a good estimate of material costs:
- Shingles, 20 squares, $33 per square on sale (we saved about a
buck a bundle, or $3 a square). Total $660.
- 3-tab shingles for ridge, 3 bundles at $10 each. $30.
- Grace Ice and Water Shield®. We've used 4 squares so far, and
we'll probably need 4 more, at $45 each. $360.
- 15# Tar paper (a.k.a. roofing felt). About 8 rolls. I can't
remember the price, but it's cheap, certainly under $150 total.
- Box of coil nails for the roofing nailer, about $45.
- OSB. We've used 36 sheets so far, and we'll probably need 30
more. At about $8 a sheet (the price fluctuates like gas prices)
this should cost about $530.
- Drip edge, 20 pieces (10' long) at about $3 each. $60.
- Assorted aluminum flashing materials, $40.
- Assorted nails, $50.
- Vent Flanges, 3, $15.
I come up with $1,940 for a total. So figure around $2,000
for about 2,000 square feet of roof (that's not the area of
the house). A buck a square foot, including new sheathing. Not bad.
We also bought some tools for this job:
- Bostitch pneumatic coil roofing nailer, $300.
- Roof jacks, adjustable, 12 at $6 each. We already had another
12 jacks. Figure $150.
- Various 2x10 planks for scaffolding, about $40. Reusable.
- Materials for homemade ladder-stairs, about $40.
Time: Based on the first half of this project, I figure
there will be 5 man-weeks of labor invested in this roof before it's
all done. I would figure 200 to 250 hours, since I usually work more
than 8 hours a day. That's a lot of time, but when broken into 4
quadrants it's not so bad. That works out to 8 to 10 square feet
per hour of labor, but I work at a decently relaxed pace on the
roof. Professionals probably are much more productive, but I don't
We could be saving around $6,000 to $10,000 by doing this work
ourselves. That works out to between $24 and $50 per hour. I wish
I cleared $24 an hour on a regular basis.
When you pay a contractor, you're not just paying someone's
wages. You are paying for a lot of overhead costs like worker's
compensation insurance (very expensive for roofers) and liability
insurance, which covers them in case you sue them because
they dropped a hammer on your head. You don't need liability
insurance for yourself. Being self-employed, I'm prohibited by law
from buying worker's compensation coverage for myself... I guess
there's too much room for fraud in the system. If I hurt myself,
nobody's going to pay my lost wages, but at least I have medical
Speaking Of Safety: Tips On Not Dying:
I would say that the biggest risk arises from climbing up and
down the ladder to get to and from the roof. Climbing with tools in
your hands is a really good way to lose your balance. That's why I
insisted on using the buckets and rope for hauling everything.
The next greatest risk is probably the chance of losing one's
balance near the edge of the roof. When working higher up the roof,
there is little chance of falling off because there are several rows
of planks to stop you.
There is another hazard during roofing: Getting hit by falling
objects. It is necessary to throw things from the roof. In both
of these phases of our project there were entry doors that people
could walk out of and be struck by debris. Some common-sense
- If you drop something while working on the roof, yell "Heads
Up" so people have a chance to react.
- When you walk out a door in a danger zone, say something to
alert people on the roof. I like to come up with creative
things to say, such as "Don't shoot", "Hold your
fire", or "Elvis has left the building".
- When you are about to hurl a large chunk of shingles from the
roof, and you aren't sure who might be below, say something.
- People have a habit of coming and going from their houses and
not being the least bit concerned about junk falling from the
sky. Everybody around a re-roofing project needs to adjust their
habits for a few days. Maybe posting a sign on the inside of the
door will remind people. Or tie a bell to the door so you can
hear it opening.
- Remember, it only takes 600 inch-pounds of kinetic energy to
cause a fatal skull fracture. This means that a 10 pound
object falling from 60 inches (that's 5 feet) can kill somebody.
A 2 pound object falling from 25 feet can do the same.
See: Index of
- Pneumatic Roofing Nailer
- Basic Carpentry Tools
- Chalk Line
- Architectural Shingles
- Plain 3-Tab Shingles
- Roofing Nails, 1-1/4"
- Self-Adhesive Shingle
Back To Top
What's New Project