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STRIPPING AND FINISHING WOOD TRIM
By David Dunnison
Stripping is one of my least favorite activities.
Over the last years, however, I have
accumulated lots of experience with many different
strippers and techniques.
If you have an older house (e.g. Arts &
Crafts or Victorian), it is highly probable
that your internal trim was originally stained and not painted (though some Victorians
may have had ‘faux’ grain applied
which was an artwork unto itself). Depending
upon the location and elegance of the home,
each was originally trimmed out with select
oak, mahogany, heart pine, redwood or Fir.
These beautiful woods deserved to have their
grain exposed as they would have been originally
Unfortunately, as these houses aged, previous
owners may have decided to brighten them up
and paint over the original trim. As these
paints age, they tend to look far worse than
the original finish. Restoring your
house to its former glory and beauty may require
some extensive paint stripping. In my house,
given the size of the job, I received considerable
advice not to bother with stripping and refinishing.
As much as I loathed stripping, the results
have always been rewarding. Even more fortunately,
I have become much more efficient at stripping
so it is now a minor nuisance.
All chemical strippers are nasty. Whenever
possible I avoid them completely and just
use the heat gun approach (see below). Unfortunately,
it is difficult to completely avoid chemical
strippers. Window sashes, inside corners,
and complex moulding patterns often offer
no other choice. While I can’t remember
the source, I recall one article noting that
even so-called environmentally friendly strippers
are hazardous.
Strippers are designed to remove paint, which
is tougher than wood, skin, lungs or eyes.
Protect yourself! As for protection, I prefer
using a face shield over goggles as it is
easier to adjust the face shield without touching
your skin than it is to adjust or remove goggles.
A face shield also protects more facial area.
The more you cover up, the happier you will
be.
In my experience (backed up by various articles),
the most effective strippers contain methylene
chloride. I find liquid-based products much
better than the gel-based products. The gel
products contain a wax that is supposed to
help slow down evaporation, but it doesn’t
work as fast.
I have been very happy using “Circa 1850
Furniture Stripper” (http://www.swingpaints.com/1800.htm).
It works fast, is easy on wood, doesn’t
affect the new finish and doesn’t appear
to damage window panes. Feel free to experiment,
however, as the actual type of finish you
are removing may respond more favorably to
one type of stripper or another. Do not use
alkali or lye-based products unless you are
comfortable with blindness or the need to
ultimately disassemble and rebuild your doors,
window sashes, etc. While lye strippers will
completely dissolve the paint, they also damage
glue.
If you are using methylene chloride-based
products, it has been my experience that no
matter what kind of gloves you wear, it will
eventually begin to sting as it appears capable
of permeating just about anything. I usually
wear an inner cotton glove with my outer gloves
and will go though more than one pair of gloves
during stripping. You will know instantly
if even a small drop touches your bare skin.
Chemical stripping is not a T-shirt and shorts
job. These strippers will also go through
your favorite jeans in an instant – aprons
are a good idea. The stuff works by going
through the paint and lifting it off the surface
of the wood as opposed to dissolving it from
the outside, hence its ability to go through
gloves. Hopefully you will have most of the
paint off before your hands sting. If and
when it does, wash your hands with lots of
cold water and you will start to feel better.
Definitely wash your hands before touching
any other body parts!
In the stripping process, it is very difficult
not to damage or alter the underlying wood
or original finish. Even if the stripper doesn’t
raise the grain, you may use a water-based
or alcohol-based product later that will.
In the overall process (see Refinishing),
this is virtually unavoidable. In addition,
you will need to use scrapers, picks and steel
wool, all of which can damage the wood. Steel
wool is like sandpaper. The coarser and more
effective the steel wool for removing paint,
the more likely you will sand or scratch the
underlying wood. Similarly, stripping tools
are likely to gouge or splinter the wood.
Creating splinters is particularly problematic
on softwoods (e.g. Fir, pine, etc.) and aside
from jabbing into your fingers, it can really
mess up the appearance of an otherwise beautiful
piece of wood. While it appears counter-intuitive
as wet sanding removes material faster than
dry sanding, keeping the piece wet with stripper
appears to help minimize the damage. If you
are careful with how you use the tools and
work with the grain, you will be surprised
at how little damage appears to be done.
Note that for some reason, methanol (CH3OH)
is almost never called methanol. Methanol
is also known as wood alcohol, methyl alcohol,
methyl spirits, and methyl hydrate. Even with
a chemistry degree, it took me some pondering
to figure this out. Methanol is one of the
most useful solvents for stripping and refinishing,
especially if there is any shellac present.
Whatever it is called where you live, make
sure you get some.
Given all of the nastiness and mess of chemical
stripping or even the heat gun approach, I
prefer to remove the piece to be stripped
(e.g. door, casing, etc.) whenever possible
and work on it on a temporary table I create
with a piece of plywood (commercial strippers
use shallow stainless steel tanks). This keeps
the mess very localized and in a safe place
away from other finished wood, children, pets,
etc. It is also much easier to work on something
that is horizontal at waist height than on
something vertical. Being horizontal further
helps in keeping the piece wet with stripper
since it doesn’t flow off as easily.
Chemical Stripping Technique: |
 Apply
stripper, stripper and more stripper |
| Scrape
off paint |
| Wash
with solvents (these are also mild strippers)
|
| Scrape
and pick |
| Repeat
appropriate steps as necessary |
In a well-ventilated area, apply liquid stripper
generously with a paint brush. Keep the piece
wet with stripper until the paint begins to
soften or lift. The process of applying the
stripper will actually begin to remove a lot
of paint, though you may go through more than
one paint brush (use the inexpensive, made-in-China
bristle brushes) and may soon have large puddles
of used stripper. I have read about and tried
various techniques such as putting plastic
wrap over the piece to help keep it moist.
This has never really worked for me. The fastest
technique is to keep applying the stripper
with a paint brush.
Tools: |
| Natural
bristle paint brush |
| Flat
scraper |
| Corner
or round scraper |
| 1-1/2”
flexible spatula |
| dentist
picks |
| Medium
steel wool |
Using a scraper or a flexible spatula, remove
as much paint as possible and then reapply
the stripper. You will need to keep your tools
clean, so plan for this and keep your scraper
sharp (use a carbide blade or keep a file
handy to sharpen the metal scrapers). Old
paint is abrasive and will dull scrapers.
I use the spatula to clean the gunk off the
scraper and vice versa.
Follow the scraping with steel wool dipped
in stripper (to keep it wet and to get rid
of the removed paint). Depending upon the
piece, I often start with relatively coarse
‘medium’ (‘0’) steel wool.
I buy it by the roll, and cut 6 – 8”
pieces off with scissors. While it is relatively
abrasive and more likely to splinter the wood,
it absorbs more paint, rinses better and cuts
through the paint faster than finer steel
wools. “Scotch Brite” pads also
work well, but they are more expensive than
steel wool and you will likely go through
a lot of them.
Rather than use scrapers or steel wool, “The
Furniture Guys” on TV swear by planer
shavings. As many times as I have watched
them do this and as easy as it looked, however,
I have never been very successful with it
and you need lots of planer shavings.
Planer shavings would be a lot easier on the
underlying wood, however. For a fine piece
of furniture, I would definitely start with
planer shavings. Also, some woods (e.g. cherry)
can react with the fine dust from steel wool
(metal tools are o.k.) and you should use
either Scotch pads or planer shavings.
Bottom line, chemical strippers are always
harder to use than it appears on TV.
Once you get down to cleaning out the corners,
dental picks will become your best friend.
At times, it seems like this is the only device
I use for whole pieces and even whole rooms.
I have used various types of brushes (wire
brushes, toothbrushes, scrub brushes, etc.).
While these will work, they gum up with stripped
paint fairly quickly and then become ineffective.
Stick to the cheap paint brushes and keep
applying stripper.
The Heat Gun Approach
Now that we have mastered chemical strippers,
let’s avoid them completely. When I have
flat surfaces (though it does work well with
window sash mullions – careful not to
crack the glass), my favorite technique is
to use a heat gun and a 1-1/2” flexible
(not stiff) spatula. It is faster and safer
than chemicals and the cleanup is much easier.
Be careful not to burn the wood or start a
fire with the paint, though.
This method often works slightly better on
a vertical surface since heat rises. Starting
at the bottom, heat up the paint until it
starts to bubble. Push the scraper into the
soft paint until you get under all of the
paint and right down to the wood. Moving the
heat gun up the piece, continue to lift and
scrape off the paint with the spatula. Once
you have mastered the technique, to your great
satisfaction, you will remove long ribbons
of paint. You should be able to remove at
least three coats of paint at a time with
this technique and ideally all coats will
come off with one stroke. Wow, was that fast!
As the heat gun loosens up more paint than
you strip off at any given time, you may find
that ‘cold stripping’ works as well.
Using your metal spatula or a dental pick,
carefully lift up any loose paint edges and
then go to town. You may find that you can
remove large portions of paint this way.
In terms of safety, keep in mind that the
heat gun and melted paint are very hot. Your
fingers will appreciate your remembering this.
Also, some fumes may be released from the
paint.
Once you have taken off all the paint that
you reasonably can with this technique, use
a good quality, sharp scraper and scrape the
surface to smooth it out and get rid of any
little bits of paint left. A dental pick can
be very helpful. Work with the grain, or at
an angle to it, but not across or against
it. Inside corners are hard, but patience
pays off. Lee Valley Tools sells a heavy duty,
two-handed carbide-tipped scraper that I have
fallen in love with (www.leevalleytools.com).
I will not abuse this scraper with chemical
stripper and save it for clean up.
Even though it is faster than chemical stripping,
the heat gun approach can still be very tiring
as you have to use a fair amount of physical
effort to lift the paint. Using this technique
I once completely stripped the wainscoting,
including some very detailed moldings, along
a 14 foot long wall in under eight hours.
Preparation
Once you have removed the paint with either
chemical stripping or the heat gun technique
or a combination, the underlying piece probably
looks pretty terrible and has bits of paint
left or messed up finish left. Don’t
despair, however, as you will surprise yourself
with how well it will come back.
For starters, you should neutralize any remaining
stripper, even if the manufacturer says you
don’t have to, and remove any remaining
uncooperative paint or finish. Once you have
felt the sting from the stripper, you will
agree that neutralizing is a good idea if
you don’t have to. Use a 50:50 mixture
of methanol and lacquer thinner to wash down
the piece. Water may neutralize stripper,
but this 50:50 is mixture is much better as
it is actually a very effective stripper itself.
As with stripper, use a lot. I usually apply
and wipe with either Scott “Shop Cloths”
or ‘0000’ steel wool. If you started
with just a shellac finish, forget all of
the above as this mixture is the only stripper
you will likely need. To determine if it is
a shellac finish, put some methanol on a cloth
and rub on the finish. If it turns brown and
appears to be dissolving the finish, it is
shellac.
The 50:50 mixture of methanol and lacquer
thinner dries fairly quickly (solvent hazard!).
Once it does, you may need to sand the wood
to deal with any raised grain. Use a relatively
fine sandpaper (e.g. 100 grit or finer) and
touch it up as required. You shouldn’t
need to be too aggressive with the sandpaper
if you have done a good job with the 50:50
wash.
Refinishing
Having removed the unwanted old finish, your
piece is ready to be brought back to its former
glory.
Ultimately, you want to match color, sheen
and texture. While a variety of staining and
coloring techniques were used, in the many
houses I have seen, medium walnut stain combined
with de-waxed (i.e. filter it through cheesecloth)
orange shellac does the trick (a 2 lb cut
works best for me, but I am still learning).
Original finishes that were available 100
years ago included shellac, tung oil, linseed
oil, and varnish from pine sap. Varnishes
have pretty much been replaced now with synthetic
products (e.g. urethanes). As simple my stain
and shellac solution sounds, it took me years
of experimentation and research to figure
this out.
To match original stained Fir woodwork exactly,
I add 2 ounces of black per gallon to the
medium walnut stain. For an even color, it
is critical to keep stirring your stain as
the pigments seem to settle out more quickly
than with paints. Fortunately, as stain and
shellac dry and cure fast, it is possible
to refinish your woodwork very quickly. You
can complete entire rooms in no time. Don’t
get too far ahead of yourself, however, as
stain dries fairly quickly and may dry before
you wipe it off.
I generally apply stain for about five to
ten minutes, and then wipe it off. Wiping
is a bit of a misnomer, as the best technique
to removing the stain and having a nice even
color is more akin to polishing. Careful that
you don’t snag any slivers when you wipe
down the stain or you will tear off wood and
have to retouch the bare wood with more stain.
Even if it looks dry, wait for a couple of
hours before applying the shellac as it can
thin out and remove the stain. Like the stain,
a 2 lb cut of shellac also dries fairly quickly,
and if you get too far ahead of yourself,
you will produce a very uneven finish.
If you have horizontal surfaces (e.g. counter
tops), you may want to protect them with more
than just shellac. In this case, you can start
with one or two coats of shellac and then
use tung or linseed oil by themselves or mix
them with varnish. Note that I don’t
like urethane by itself as it tends to crack
over time and is hard to repair without restripping
it completely. Other than shellac, my favorite
finish is the ‘Sam Maloof’ finish
or a derivative of it. Combine 1/3 gloss varnish
with 1/3 tung oil (or linseed oil) and 1/3
turpentine (paint thinner does not work as
well) and apply this like a finishing oil
(apply, let it sit for a few minutes, and
wipe off the excess). As Sam Maloof is a woodworking
god, I feel that this finish must be good
enough for old house trim. Use the recoat
information from the varnish as a guideline
for additional coats. If you can’t get
real varnish (everything is getting discontinued
these days), you can substitute urethane.
Once you have built up a number of coats,
you can adjust the sheen with steel wool.
In other words, if you don’t want a gloss
finish, rub the finish with ‘0000’
steel wool – again working with the grain,
not against it. Paste wax is also recommended.
If you use Tung Oil, wait at least a few days
for the finish to harden before rubbing with
steel wool (a month is even better). Note
also that urethane by itself can take a while
to fully harden. One of the advantages of
the Maloof finish is that since you wipe it
off, you never get dust, bristles or drips
messing up your finish.
Don’t take my formula for granted, however,
and experiment on a small piece first and
then adjust as required. You may want to take
an old piece with original finish into your
neighborhood paint store for fine tuning.
Note that the Shakers did not use stain and
applied linseed oil followed by shellac to
get that nice tone on their pine cupboards.
If you are patching with new wood, you must
sand this first. Particularly in the Arts
& Crafts period, craftsmanship was the
rule. While it may appear smooth, there will
be planar marks on new lumber. Your original
woodwork would have been sanded smooth and
if you don’t do this with new wood, those
planer marks will stick out like a sore thumb
after the finish is applied. Since shellac
raises the grain, you may want to address
this before finishing the new wood. Methanol
can be used to prepare and clean the wood
as well as raise the grain.
|
| Sand
out the planar marks with 100 grit |
| Sand
with 120 to 150 grit for desired smoothness
|
| Wipe
with methanol to raise the grain (or water
if you prefer, but you will have to wait longer)
|
| Sand
when dry with 120/150 grit to smooth out the
raised grain |
| Stain
(you can leave the sawdust on the wood as
it will fill the wood pores and provide a
smoother surface) and wipe (removes excess
stain and sawdust) |
| Seal
the wood with one or two coats of shellac
(1 – 2 lb cut) |
| Apply
finish (additional shellac or oil, varnish
or Maloof finish) |
Make sure you sand with a good random orbit
sander (turn it on when it is on the wood
to avoid swirl) or sanding blocks (always
sand in the direction of the grain). Hand
sanding with fingers only can produce contours
from your fingers, and belt sanders are too
aggressive.
Be very careful when sanding the finish between
coats. Shellac is a very good sealer and also
bonds to itself very well. If you sand through
the shellac and remove stain, even reapplying
the stain will not solve the problem. You
may need to wash off the shellac with methanol,
and start over again. I generally don’t
sand until at least the second coat of shellac
(very lightly if applying an oil finish) or
until after the first or second coat of oil
finish.
Hopefully these pointers will help you quickly
master refinishing your old trim. Don’t
be afraid to experiment as you may come up
with your own formulas and techniques that
improve upon these. There is one spot in my
house where I have an original, untouched
piece of wood along with a refinished piece
and a new piece. Thus far, nobody has been
able to correctly identify the three of them.
|
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HOW CAN I INSULATE
MY HERITAGE HOUSE?
I have single pane windows and my walls
are not insulated. What can I do to keep out
the cold without having to replace my beautiful
original windows and lath and plaster walls?
This is one of the most frequently asked
questions by homeowners who are being pressured
by commercial interests to replace their single
pane windows with double-glazed sealed units
and to remove their plaster walls and install
batt or blown insulation. However, given the
high cost of new windows and insulation, you
are unlikely to ever save enough energy to
pay back your investment. Fortunately, there
are far less expensive and destructive way
to improve the energy efficiency of heritage
homes.
In terms of insulation, the key is to focus
on the attic. As heat rises, this is where
most of the heat is lost. Don't worry about
insulating the walls of your house - focus
on the attic. That is where you will get the
greatest return on your costs. Another consideration
is that blown insulation can cause serious
problems as it can settle over time, introducing
a super-insulated band around each floor,
which will retain moisture in the walls -
a very bad thing!
The Foundation DOES NOT ENDORSE the replacement
of original windows but rather encourages
a rehabilitation approach through upgrading
the thermal efficiency of the existing window
sash.
The introduction of double-glazing will cost
you more over the life of the house than you
will save in energy, as the sealed units fail
and have to be replaced about every fifteen
years. The original windows have lasted for
decades if not centuries and with some maintenance
will likely last at least that much longer.
When trying to gain energy, look for major
drafts around windows and doors. For the air
pockets around windows you can remove the
trim on the inside and put in rigid insulation.
This can be held in place with Tuck Tape and
will not interfere with the operation of the
sash pulleys. In so doing, however, the trim
is likely to be damaged as fir splits easily.
Thin spring metal weather stripping is also
ideal for insulating traditional windows and
doors. Storm windows are the traditional way
that windows were protected during winter,
and would represent a huge improvement in
the thermal efficiency of your house.
Another neat trick for double hung windows
is to seal the inevitable air passages on
the sides and where the pulleys are with a
small piece of insulation or even sash cord.
If you string a piece of fiberglass insulation
in under the sash cord so that the sash cord
holds part of it against the pulley, you can
then easily remove it by pulling on the cord
in the spring and not have it pile up inside
the window trim.
A few last general suggestions on gaining
energy efficiency in old houses is to think
about hanging lined, full-length drapes and
to make sure that your doors are drop-sealed
and that proper weather stripping is in place.
If you have hot water radiators do not rush
to get rid of them. They provide efficient
and inexpensive heat.
In a nutshell, keep your original windows
and gain energy efficiency by adding insulation
around the frames and by re-hanging the sash.
Heavily insulate your attic and ensure that
you have proper weather stripping around your
doors. Consider hanging full length drapes
and keep your hot water radiators.
|
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THE
ADVANTAGES IN KEEPING YOUR ORIGINAL WINDOWS
By
Donovan D. Rypkema
(Excerpt from Economics, Sustainability,
and Historic Preservation in the
National Trust of Historic Preservation
Forum Journal Winter 2006)
Over
a year ago in Boulder, Colorado, a homeowner
in a local historic district applied to
paint his window sash and trim, and approval
was given the same day. Two weeks later
the landmarks commission learned that
the historic windows had all been removed-a
clear violation of the local ordinance-and
had been replaced with new windows. This
was done by a contractor who claims to
specialize in "ecologically sound methods"
and bills himself as " Boulder 's greenest
contractor."
The
landmarks commission sent a letter directing
that the original windows be retained
and their condition documented. The contractor
responded saying that the greater energy
efficiency of the new windows should outweigh
the regulations that apply to houses within
the historic district. A subsequent commission
hearing upheld the staff position and
a city council hearing supported the commission's
ruling.
Here's
the next chapter- a reporter for the local
alternative newspaper decided to take
matters into his own hands. He went to
the house, picked up the historic windows,
took a sledgehammer to them, hauled them
to the dump, and arranged to have a bulldozer
run over them. Sort of a 10- year-old's
version of civil disobedience. Now I want
to stop the story for just a minute. I'm
not necessarily sure that the landmarks
commission's
decision was right. But I'm telling you
the story to demonstrate our ignorance
about what sustainable development really
is. First from an environmental perspective:
1.
The vast majority of heat loss in homes
is through the attic or uninsulated walls,
not windows.
2.
Adding just three and one-half
inches of fiberglass insulation in the
attic has three times the R factor impact
as replacing a single pane window with
no storm window with the most energy efficient
window.
3.
Properly repaired historic windows
have an R factor nearly indistinguishable
from new, so-called "weatherized" windows.
4.
Regardless of the manufacturers' "lifetime
warranties," 30 percent of the windows
being replaced each year are less than
10 years old.
5.
One Indiana study showed that
the payback period through energy savings
by replacing historic wood windows is
400 years.
6.
The Boulder house was built more
than a hundred years ago, meaning those
windows were built from hardwood timber
from old growth forests. Environmentalists
go nuts about cutting down trees in old
growth forests, but what's the difference?
Destroying those windows represents the
destruction of the same scarce resource.
7.
Finally, the diesel fuel to power the
bulldozer consumed more fossil fuel than
would be saved over the lifetime of the
replacement windows.
The
point is this: Sustainable development
is about, but not only about, environmental
sustainability.
.
Repairing and rebuilding the historic
windows would have meant the dollars were
spent locally instead of at a distant
manufacturing plant. That's economic sustainability,
also part of sustainable development.
.
Maintaining the original fabric is maintaining
the character of the historic neighborhood.
That's cultural sustainability,
also part of sustainable development.
WEATHERSTRIPPING:
A GOOD INVESTMENT FOR ORIGINAL WINDOWS
by Bruce Irving, This Old House Journal
Unlike, say, its
rotted porches or crumbling chimneys,
the windows on Christian Nolen and Susan
Denny's 1886 Victorian were in pretty
darn good shape. Large double-hungs, with
those on the rear bay graced with curved
sash and panes, they probably dated from
around 1915, when the house underwent
an extensive expansion and renovation.
"We thought about the energy savings we
might have gotten from replacing them,"
recalls Christian, "but for us, there
really was no question. They were too
beautiful to just tear out."
Their
beauty was obscured by aged triple-track
storms, so down those came-and in came
David Liberty, whose company specializes
in rehabilitating old wood windows. David
is one of the many people, including show
friend and wood repair expert John Stahl,
who believe that the strong, tight-grained
wood found in old construction makes preserving
it a better investment than replacement
with today's softer wood. Properly repaired,
claimed David, the Watertown windows would
last another hundred years.
As
David and his crew inspected each window,
they found the good old wood, without
exception, still solid and sound. The
joints were still strong. The main problem
was rattles and air leaks. The solution:
weatherstripping. First they carefully
pried off the stops-vertical strips of
wood that keep the sash in the window.
Setting them aside, they removed the lower
sash. At the same time they opened up
the sash weight ports to remove the weight
and cut off the rot-prone cotton weight
cords, which they would replace with indestructible
copper chain. The delicate parting beads,
which separate the two sash, came out
next, followed by the upper sash.
Each
sash was sanded to remove any paint ridges
that might be impeding their smooth sliding.
David cut a groove in the meeting rail
of the lower sash and slipped in a nylon
weatherstrip (supplied by John Stahl).
Into the upper half of the window frame
went spring bronze weatherstripping which,
when nailed in place and scored with a
putty knife, kicked out its unattached
edge to provide a positive pressure seal
for the upper sash to ride against. The
upper sash went back into the frame, followed
by the parting beads, another set of bronze
weatherstripping for the lower sash, the
lower sash attached to its new copper
chains, and finally the stops, positioned
carefully to allow the sash to slide but
not to rattle. New locks at the meeting
rails sucked the two sashes tightly together,
and the old windows were ready for a new
life. Cost: $175 per window.
In
love with the historic look of their restored
windows, Christian and Sue decided to
skip new storms and their obscuring effect.
They had heard that only about 10% of
a window's heat loss is through its glass,
so with the new weatherstripping and properly
caulked window casings, they figured they
might be OK. And, for the first winter,
they were. No rattles, no drafts, beautiful
sunlight streaming unobstructed through
wavy old glass.
The
following winter, bothered by the drying
effect of the hot-air heating, they added
a humidifier to the system. Good for their
skin, bad for their windows, whose single-thickness
panes immediately frosted up, some with
up to a half-inch of the stuff, melting
during the day and threatening to ruin
the paint and even the underlying wood.
So much for romance and history-storm
windows have been ordered and will be
installed this spring. Christian and Sue
found a manufacturer whose units come
with low-e glass, rounded edges on their
aluminum frames, and baked-on custom color.
Per unit cost: $250.
Had
they tossed their old windows and used
modern replacement units that slip into
the existing frame, Tom Silva estimates
they would have spent around $650 an opening.
The new units would have been mechanically
smooth, but so are the reconditioned old
ones. The new would have provided the
insulation of double-pane glass, but so
do the old windows with their new storms.
Aesthetically, the new would have looked,
well, new. By taking the route they took,
even with its unexpected bump, Christian
and Sue got what they needed and even
saved some money. But more importantly,
they saved some of the best things about
their old house.
TECHNICAL
BRIEFS FROM THE NATIONAL PARK SERVICE
Writers
working under contract with the federal
government ( USA ) have assembled more
than 40 booklets designed to help owners
and developers of historic buildings recognize
and resolve common preservation and repair
problems. The on-line Old House Journal
has collected the whole set and made them
available on-line. The following link
takes you to the index of articles:
http://www.oldhousejournal.com/notebook/npsbriefs/index.shtml
INSURANCE
FOR HERITAGE BUILDINGS
Johnston Meier Insurance has launched a new program specifically developed for the heritage house market. Johnston Meier Insurance Agencies Group (Maple Ridge location only). Please have your current insurance broker contact JM for further details or call them directly @ 604-467-4184.
- Very Competitive Premiums
- Guaranteed Replacement Cost
- Single Limit
- Up to 100% By-Law Coverage
- Comprehensive Homeowners Policy
- Free Building Appraisal on all New Policies
- Umbrella Liability available
- $500 Deductible
- 80% Content Limit
BC Automobile Association (BCAA)
- underwrite their own policies up to $800,000
- homes valued @ more than $350,000 or designated must be appraised
- May insure Knob & Tube wiring after PowerCheck inspection (see following article)
- insist on bylaw protection insurance
- Will insure both members & non-members
- 604.310.2345
Cafferky Gilding (BC wide)
- Will insure both register & designated properties
- has experience in insuring heritage houses (New West especially)
- knob and tube may be allowed
- Greg Gilding (604) 855-0420
London Drugs Insurance
- will insure heritage register properties but not designated properties
- no knob and tube wiring
- 1-800-681-6677
Atkinson and Terry (Lower Mainland)
- Evaluate insurance for heritage houses on a case by case basis
- generally will not insure if there is knob and tube wiring
- contact the Personal Lines Manager (Clay Grainger 604-596-1717)
Vancouver Holdings BC Ltd.
- Will insure heritage houses
- 260-1040 West Georgia Street
Vancouver, BC V6E 4H1
(604) 685-6354
- Contact broker: Briggette
The following companies are under review by the VHF and we are waiting for their replies to our questions regarding their extent & willingness to insure registered & designated buildings.
Canadian Heritage insurance Program
- new business making a specialty of all types of heritage property
- prepared to deal with knob and tube wiring
- Danny Sgro (416) 420-7746 / dannys@jdimi.com
Thunderbird Insurance (Victoria)
- will deal with homeowners anywhere in B.C.
- David Potvin (250) 385-9795
Canadian Direct Insurance
- 888-225-5234 (call no charge)
- Homeowner testimonials indicate that this firm will accept knob & tube wiring, and will do a free inspection
The Insurance Bureau
of Canada publishes a useful pamphlet
entitled
"Insuring Your Heritage Home"
You can receive a copy from the Heritage
Society of B.C.
e-mail: hsbc@islandnet.com
or you can download the pdf version here
"Insuring
Your Heritage Home"
ELECTRICAL DANGERS IN HOMES WITH KNOB AND TUBE WIRING
by Brian Cook, May 2007
BCTQ Electrician
Field Safety Representative (Electrical) and owner of PowerCheck
Based on about 100 home electrical safety surveys that I have conducted done over the past 6 months, I have found only one home with dangerous knob and tube cabling. In this house the hazardous knob-and-tube wiring was a direct result of over fusing which resulted in over-loading of the conductors followed by insulation breakdown. With this home I rated the home high risk and presented that the home be rewired. The homeowner has done so.
A common danger relating to knob and tube wiring is the use of electrical devices requiring grounding that are connected to “ungrounded, 3-prong receptacles” (found in virtually all homes examined). This situation, the "lack of ground" can easily be remedied with the replacement of the ungrounded 3-prong receptacles with GFCI receptacles (or GFCI protection at the panel). This is an excellent solution that in my opinion provides equal if not better ground protection than standard 3-prong grounded receptacles.
A second danger relating to knob and tube wiring is the implementation of "Handyman add-ons". These add-ons are often found, though not exclusively, tapped into existing knob and tube circuits. Handyman add-ons can be very dangerous, consisting of, for example undersized wire, open splices, poor connections and/or dangerous placement or type of device to which it is powering. My findings show that dangerous "Handyman add-ons" are not limited to homes with knob and tube wiring, but related to the age of the house. Regarding homes with serious electrical hazards, I have found a particularly high incidence in homes with secondary suites, a result of the homeowners doing the wiring themselves or by unlicensed electricians.
Interestingly, in all homes examined, I have conducted “voltage drop test under loading”, an excellent test to determine the conductivity of the conductors, thus a presentation of electrical heat dissipated in the conductors and connections enroute. Any poor connections clearly show up whether the cabling be knob-and-tube, aluminum, or modern wiring. Poor electrical connections can lead to arcing followed by fire. My findings show that if there has not been “handyman tampering” the conductivity of knob-and tube circuits has been by-in-large superior to that modern cabling. This is likely due to the soldered connections and the shorter wire runs of knob and tube wiring.
A final mention: Of significant concern is dangers of service supply conductors (home powerline). The two very dangerous concerns that have found have been (a) broken “Emily knob” (in 3% of homes) and (b) trees applying pressure to service-supply conductors (in 26% of homes), causing tension on the conductors which could lead to a broken Emily knob. Once the Emily knob has detached from the house, the service supply conductors are at high risk of becoming detached at a point close to the side of the house. This can, and has led to fire outbreak.
In summary, electrical hazards have been found both in homes with and without knob and tube wiring, but the hazards have by-in large not been related to the knob and tube wiring itself. Homes with significant hazards have by-in-large been related to (a) the age of the house (the number of years where Handyman tampering could have occurred), (b) the application of the house (secondary suite or not), and proximity of trees to the service supply conductors. A comprehensive electrical inspection by qualified personnel is the only sure way to identify if and where there are electrical hazards.
Voltage drop test under loading: Canadian Electrical Code states that at full load values within 5% are acceptable. Modern home wiring circuits typically show values in range of 4 – 4 1/2 %; Knob & tube circuits most often measure values in the range of 1 to 2%; On aluminum wiring circuits I have measured values exceeding 10%. This additional voltage drop is likely due one or more poor connections enroute to the receptacle, and must be repaired. A 1500 watt load (e.g. an electric kettle) connected to a circuit with a 5% voltage drop at a poor connection yields 60 watts heat generated at that connection. This would be comparable to the heat generated from a 60 W light bulb; most dangerous and must be repaired.
REPAIR OR REPLACE: WINDOWS IN HISTORIC BUILDINGS
Arriving at a Sustainable Solution
by Craig Sims and Andrew Powter
We tend to take windows for granted. Yet we recognize that heritage buildings whose windows have been replaced have been diminished. The depth and thickness of frames and sills, the width and visual weight of sash components, the materials, the colour and the pattern of light reflecting off the glass—all complement and elaborate the architectural style, texture and age of a building. Much of this character is lost when windows are replaced with modern versions that lack these features.
Replacement of historic windows is often driven by a number of concerns. Peeling paint, broken glass or missing glazing putty can make them look unsightly. Some may be draughty because of a sloppy fit or difficult to operate due to deteriorating sash cords. Any exposed weathered wood is often described as “rot.” One often-stated argument for replacing windows is the “desire” to improve energy performance and an “assumption” that this will be achieved by replacing the windows.
Despite the irreversible impact on the character and authenticity of the building, anticipated energy savings are rarely achieved over the long term. Removing historic windows should be a solution of last resort, not of first resort. In the residential sector the decision to replace is rarely preceded by analysis and serious investigation of the range of alternatives.
Fortunately, it is not necessary to sacrifice our non-renewable cultural resources in order to preserve our non-renewable energy resources. Usually, the most effective ways of improving energy performance in a historic building are controlling all sources of air leakage and having an efficient heat source (furnace, boiler or other). Replacing historic windows with modern sealed glazing units is one of the most expensive, short-lived, least effective, yet most popular home improvements for reducing energy consumption in heritage houses.
There are no publicly available life-cycle studies or data in Canada which assess and compare the energy performance of rehabilitated historic windows versus retrofit new windows in historic buildings. Those studies carried out in the U.K. and Norway indicate that over an appropriate life cycle, window retention and rehabilitation might even be the greenest overall solution. Despite many years of debate, publicity and numerous articles on the subject, retention and upgrade versus replacement continues to be a conservation battle.
Detailing and Durability: Historic window systems are usually built with good attention to detail (such as weather shedding) and with good quality materials (such as old-growth timber). Problems related to wear over time— peeling paint, broken glass and missing putty—can look unsightly but are easily put right. Residential wood windows can be in service for 100 years before requiring a major retrofit to remain in service for a second 100 years. Similarly, it is not unusual for modern windows to experience major, non-repairable failures to sealed units, vinyl welds, caulk joints and wood joints within 10 to 25 years. Today, most sealed units carry warranties of only 8 to 10 years.
Does Replacement Reduce Heating Costs?
Life-cycle cost analysis has shown that replacing historic windows in order to reduce heating costs is largely a myth. This notion dates back to the energy crisis of the 1970s. Unfortunately, the message was repeated by every government agency involved in helping homeowners save energy. The window replacement industry was soon born. For homeowners seeking advice on how to deal with their old window problems, a trip to the yellow pages will still result in sales pitches for replacement windows and little else. Yet, life-cycle cost analysis has demonstrated that other means are more effective for improving building envelope performance.
Many aspects of the construction industry, including those related to heat loss, are measured and regulated by the Canadian Standards Association (CSA). Some years ago CSA, in tandem with the window industry, actually developed a Canadian standard to measure window performance known as CSA A440 (see sidebar).
The most significant factor relating to heating costs and human comfort is air infiltration, that is, cold air leaking in and warm air leaking out. Fortunately, it is also the easiest and cheapest problem to solve when retrofitting old windows. The use of sealants on fixed joints in combination with weather stripping on operable joints results in significant improvements, and usually the CSA standard can be met.
CSA A440 also rates weather shedding performance. Because the construction and detailing of traditional windows has evolved to include drip designs and angled sill slopes that ensure water sheds effectively, they tend to perform very well under these two parts of the standard. (Anyone who bought condominiums in British Columbia a decade ago will be aware of the importance of designed-in weather shedding.)
Does Replacement Reduce Maintenance?
There is no question that historic wood window systems require maintenance. Windows have to be washed and painted on a regular basis. If painting is neglected for too long, then glazing putty may need touching up or replacing. Sometimes broken sash cords on double-hung windows have to be replaced—especially if they are brittle from being painted. The good news, however, is that historic windows are maintainable.
Modern window systems, by comparison, are usually touted as maintenance-free. Although they may not require painting or glazing putty touch ups, they still need to be washed and cleaned. A host of maintenance issues unique to modern windows arise. For instance, most modern window systems incorporate double glazing in the form of a sealed insulated glass (IG) unit. The integrity of the wet seals, i.e., small caulking beads around the perimeter of the glass inside and out, must be maintained to protect the edge seals of the IG units from light and moisture. When the seal fails, condensation and eventually scum and mildew within the interstitial space will result (see sidebar).
Because IG units are commonly installed as part of the window manufacturing process, their replacement often means replacing the entire sash. If the manufacturer still exists—and still makes that same window model—it may be possible to replace the sash; but if the models have changed, the entire unit has to be replaced. Finding the proprietary hardware can also be a problem.
“Maintenance-free” is often industry double-speak for un-maintainable or disposable. Vinyl- or aluminium-clad windows do not require the cyclical painting that wood does, but they scratch and fade, factory applied sealants fail, and joints may separate. These forms of deterioration cannot be halted by maintenance.
In the last few years the advice to homeowners from the window replacement sector has been that responsible homeowners should replace their windows about every 25 years. So much for payback!
Issues of Sustainability
What makes a “green” window? Green building is about using fewer non-renewable resources. It is not only about reducing your personal, government-subsidized monthly heating bill. It is about the overall impact on the environment. Wasting a window’s embodied energy—the energy used to extract raw materials, manufacture, transport, install and maintain—is wasting a previous energy investment. When traditional windows are stacked on the curb for disposal, energy resources must still be expended. Fuel is required to take them to the landfill and to bulldoze them in when they get there.
The most energy-efficient window is one which is responsible for less consumption of energy across its entire life cycle, including its manufacture, shipping, time in service and its eventual disposal or recycling—not just its performance rating on the day it was installed, which is how CSA A440 rates windows.
Remember, glass and aluminium are two of the most energy-dense building materials requiring the highest use of energy in their manufacture and recycling. Vinyl is a non-renewable petroleum product and is not bio-degradable.
What do we hear about payback? Payback is the time it takes for the money you save on heating fuel to equal the money you invested in your retrofit. Payback on replacement residential windows, if it can be determined at all, usually falls within 40 to 100 years. That is commonly two to four times the service life of the window you have just installed.
Window replacement is now a major industry that is supported by utilities, lenders and insurers (think of the inserts in your last electricity bill). Surprisingly, there is very little data which allows the homeowner to make a “business” comparison between various upgrade options and full replacement. Perhaps that is because what data does exist indicates that over a 25-year period, upgrading is a more affordable energy-saving alternative to full replacement. To make an informed decision, homeowners need to be able to assess the performance of their existing windows, to be aware of the various retrofit options available to them and to estimate how much difference various improvements are likely to make.
Craig Sims is a heritage building consultant based in Kingston, Ontario. Many of his projects involve building envelope work, including the restoration and upgrade of windows.
Andrew Powter has been involved in heritage programs and projects both nationally and internationally throughout his career. His main areas of interest include historic wood structures, building envelope performance and sustainable heritage conservation practice.
WINDOWS IN HISTORIC BUILDINGS: SUSTAINABLE, REPAIRABLE
By Susan D. Turner
Windows are often described as “the eyes of a building.” Their size and spacing create rhythm and balance in the façade that may be emphasized by deliberate shadow lines and relief; their materials and operation type may reflect the state of technology for their time. For many building types and styles, windows are a key character-defining element.
However, as interest in energy conservation and sustainable development increases, and building owners look for ways to improve energy performance, old windows are a common target. Window replacement is often mistakenly identified as one of the top energy-saving improvements that can be made. Yet windows are also important character-defining elements to a building’s architecture, and the Standards and Guidelines for the Conservation of Historic Places in Canada encourage owners of heritage buildings to “repair rather than replace character-defining elements.” Fortunately, it is possible to improve the thermal performance and operation of old windows while at the same time respecting heritage character (and often even saving money into the bargain).
Repairing and Upgrading Windows is a Green Thing To Do
Windows represent embodied energy: raw resources, processing, labour, and shipping energy have gone into their manufacture. Embodied energy is lost when windows are sent to a landfill. When even more energy and resources are invested in replacing them with new windows made of wood, aluminium or vinyl—often with a shorter service life than the old windows—the cost to the environment is substantial. This is above and beyond the cost to the building’s character and heritage value when original features are lost. When properly repaired and retrofitted, early windows can usually be made to perform at a level comparable to new windows. This approach is ‘sustainable’ on many levels. Old windows are often built of old growth lumber with good construction details, resulting in an assembly that is more durable and more easily maintainable than new replacement windows. If maintained, they can last for decades, with the result that repair costs over the lifecycle of the building compare favourably with the cost of periodic replacement. Repair costs usually reflect an investment in labour that benefits the local economy, rather than harvesting resources or shipping products from a distant manufacturing location.
Determining the Best Approach
The argument for replacing windows often begins with a perception of deteriorating materials and heat loss. However, there are simple repairs and upgrades that can be done by the building owner or by a tradesperson. Selective repair or replacement of parts and the implementation of a maintenance program are sometimes all that is needed.
It is important to carefully assess the condition and performance of the existing windows. Begin by documenting the condition of each window. Simple drawings can be used to locate and number each window, and document areas of decay, broken putty, missing hardware, or other problems. These will be useful in obtaining several comparable price quotes, should you choose not to do the work yourself.
First Line of Defence: Tackle Sources of Air Infiltration
Making windows air- and weather-tight is often the most effective and least expensive step. This may include replacing broken glass, re-setting panes using linseed-oil-based glazing putty and glazing points, and painting the sash and putty lines to create a good seal against air and moisture.
There are many weather-stripping products on the market: high-quality metal weather-stripping (such as copper or lead-coated copper) is well worth the investment.
Finally, find replacement hardware for missing pieces. Window locks are important in maintaining pressure on the weather-stripping to reduce draughts.
Secondary Glazing
Single-pane windows (one layer of glass) may suffer from condensation when interior air is warmer and more moist than exterior air; they may also “feel” cold and draughty even if they are air-tight. Traditional storm windows result in a warmer glass surface by providing an additional space and pane of glass to temper the indoor environment from the exterior. In effect, this is a low-tech version of “double glazing.” Another simple option is to add new interior or exterior removable glazing panels. Always ensure that the layer of glass on the warm or interior side is the one that is air-tight. Retrofitting is generally less expensive than wholesale replacement and it permits the retention of the greatest amount of historical material.
Conclusion
Repairing and retrofitting windows is a sustainable course of action that protects the character of a historic place and respects the environment.
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