A cautionary tale and call for advice:

I'm doing a full tear out replacement with aluminum clad wood windows.

Some research on the internet turned up Marvin, Weathershield,
Jeld-Wen, Hurd, Semco,
Loewen, Peachtree, and Kolbe as making aluminum-clad wood
gliders/sliders.

In the process of vetting about 10 installers in the DC area and
hitting window showrooms, Home Depot, real lumber yards, I had never
encountered an actual glider until today. What I heard is "the
construction is very similar to this double hung I can show you", which
was sometimes accompanied by the salesman turning the double-hung
sideways and moving it back and forth, saying "see?"

Well, it's not the same, to state the obvious. To begin with, in a
slider, gravity pushes the window against the track, but in a DH,
gravity pulls it across the track! Furthermore, confirming by
inspection that a company makes a good double-hung does *not* indicate
they make a good glider.

For example, I thought the DH Weathershields I had seen were passable,
but I finally tracked down a Weathershield glider today and what a
piece of garbage it was! Standing directly in front of the window, I
had difficulty getting it to slide open. First it was hard to budge
and second once it budged it kept bucking -- catching on the leading
edge and rising up on the trailing edge. Plus the cladding job was
abysmal.

OTOH, I leapfrogged the local Marvin showroom, where they don't have a
glider, to visit the one in Northern Virginia where they do have one,
and it's as well-made as everything else by Marvin, for whom I do not
work nor do I derive direct or indirect benefit from plugging them.
Part of the reason for the smooth operation is the fiberglass strip
inside the groove in the base of the window that runs along the track.
What's more, I called Marvin HQ and a nice Minnesotan spent twenty
minutes on the phone with me explaining the finer points of their
construction, gave me his name and direct number and told me to call
back anytime.

After calling dealers listed on their websites, I've concluded the rest
of the clowns mentioned above don't bother making examples of their
full line of products available in the DC area.

If anyone knows differently and can point me to a showroom, I'd be
delighted to check them out. I'd love to discover I have options for
a decent aluminum-clad wood slider other than Marvin, since Marvins are
very dear, but I have to be able to hold the competitor in my hands. I
won't drop $20K installing a product in my house sight unseen.

Cheers,

ccsikyr

is it possible they are not common to your climate due to condensation,
freezing, or ocean salt air corrosion?

buffalobill wrote:
is it possible they are not common to your climate due to condensation,
freezing, or ocean salt air corrosion?

Nope. Washington DC isn't known for excessive amounts of those things.

The more likely explanation is that the market for good gliders is
small. My neighborhood is full of 50's houses that were built with
all-metal aluminum gliders. Most of them have been replaced, and I
don't know of a single example of a house that didn't use solid vinyl
replacement windows. Among houses that use windows based on wood, the
dominant choice around here is double hung. So companies that blow off
the wood glider market are following a certain economic logic.

ccsikyr wrote:

If anyone knows differently and can point me to a showroom, I'd be
delighted to check them out. I'd love to discover I have options for
a decent aluminum-clad wood slider other than Marvin, since Marvins are
very dear, but I have to be able to hold the competitor in my hands. I
won't drop $20K installing a product in my house sight unseen.

Why only aluminum clad? The Andersen vinyl clad glider is a very nice
window. Very tight.

R

Dealer's choice.

I don't doubt Andersen makes a decent product, but I'm skeptical of
vinyl in general.

Over time, after a beating from wind and rain, I think aluminum will
hold it's shape better than
vinyl. There are examples all over my neighborhood of vinyl windows
coming apart, not even five years after installation.
Granted, they aren't Andersen.

I'm open to persuasion, though.

Why use sliders, they are poor by design as you see, tracks get ditry in
a week. Casements are a proven design, with a positive air seal, they
have less air infiltration due to the pulled tight design. Air
infiltration is usualy overlooked in ratings but accounts for half of
heat loss on old windows. Check ratings, learn the ratings, everything
is rated independantly on good windows.

One thing to think about is resale - which product is better for that.
In my neck of the woods, AL doors and windows go on mostly lower end
homes - exception being clad AL. A lot of higher end homes are using
the better vinyl windows. Unfortunately there is a lot of vinyl junk
out there. One of the better pure vinyl windows/sliding doors in
Vinylcrest's top line. Beware they also make a lot of builder crap
also. Kolbe is mostly builder crap.

I really question the durability of wood clad with either vinyl or
aluminum. Most of it I have seen is not sealed on the unseen surfaces
- windows sweat - wood soaks it up and then you have mildew and rot.
What is a person to do.

Oh I would specifically avoid any local vinyl/aluminum fabricator -
they have all kinds of deals with local installers. Find your own
installer - when you go through someone like HD - they take 40% of the
installation up front leaving the installer scraping to make a living
from what is left forcing him to cut corners to survive.

good luck

m Ransley wrote:
Why use sliders, they are poor by design as you see, tracks get ditry in
a week. Casements are a proven design, with a positive air seal, they
have less air infiltration due to the pulled tight design. Air
infiltration is usualy overlooked in ratings but accounts for half of
heat loss on old windows. Check ratings, learn the ratings, everything
is rated independantly on good windows.

I can't comment on sliding windows in general, but I can tell you that
no window I've ever installed pulls and seals tighter than the Andersen
gliders. It's more energy efficient due to it's tightness and lower
air infiltration - check the ratings.

R

ccsikyr wrote:
Dealer's choice.

I don't doubt Andersen makes a decent product, but I'm skeptical of
vinyl in general.

Over time, after a beating from wind and rain, I think aluminum will
hold it's shape better than
vinyl. There are examples all over my neighborhood of vinyl windows
coming apart, not even five years after installation.
Granted, they aren't Andersen.

I'm open to persuasion, though.

A sure sign of intelligence.

I'm working on a project right now that has 25 year old Andersens. No
problem getting replacement hardware, screens, whatever. That's a
major benefit if you plan on staying in the house for years. The vinyl
has the color throughout and is clad over wood. On some of the windows
painters had slopped some paint on the vinyl, old caulking had to be
removed to install new flashing, etc. With the vinyl I can be pretty
heavy handed and just scrape the old paint and caulk off. I clean up
the last remnants by scraping a razor blade along the vinyl. The end
result is a clean, white window. Try doing that with aluminum and
you'll have a clean mill finish aluminum window.

I don't think Andersen is the "best" window out there, but I think it
has a good price point and the widespread use and long history are
major benefits. Check out an Andersen glider in person, they're
nothing like the casements or doublehungs. Much beefier.

R

New developments this morning that may be of interest:

(1) In an effort to be more flexible and consider vinyl-clad (as
RicodJour suggested), my wife called all around the area to HD and
others listed as selling Andersen. No one we've contacted has an
example to show us. One installer gave us an address of an install
they did to go look at. It's in Baltimore (We're in DC, and no, it
isn't all the same metro area.) That should give you an idea how
common what we're looking for is.

Exasperated, she called Andersen HQ, and was forwarded to the Carlisle
PA office, where they distribute for our region. They confirmed they
don't sell many vinyl-clad wood gliders in our region. Well, we're
thinking of dropping $20K on buying windows from you, and we'd like to
see one first, can you arrange to get one to our contractor for
inspection, she said. His response,

"No, Andersen doesn't have a program to do that."

Keep in mind, they're shipping millions of dollars worth of windows to
the DC area every month. They can't squeeze an extra window on one of
those trucks? Now, I don't think that bodes well for service in the
future.

Compare that response to the response to my experience talking to
Marvin in the original post for this thread....

(2) Turns out there is a lumber yard with Loewen gliders in the
showroom in N VA that I'm headed out to look at on my lunch hour.

Good tips. Thanks.

On the resale issue, I expect a decent aluminum clad would beat a vinyl
replacement window.
The clads typically go on high-end homes around here, as in "overlooks
championship golf course".
That's not the kind of house I have, by any stretch, so if anything,
I'm putting in a window too rich for the
neighborhood and won't get all the money back, I expect.

Interesting point about local fabricators, and I wouldn't let HD
install a doorbell, let alone a window.

I've heard a couple stories about rot on aluminum clad, particularly
with regard to Pella.
That, in fact, is what I was talking to the Marvin guy in Minnesota
about.
My reasoning was the aluminum cladding will be subject to the same
temperature gradient as the aluminum in my old solid aluminum windows.
That is, cold air outside, warm air inside = condensation. And the
condensation will be hidden inside the cladding where it will rot out
the wood and I'll never see it! His response, which I am inclined to
believe, absent a reason not to, is that the air on *both* sides of the
cladding is cold, so there should be no condensation. The air pocket
between the cladding and the wood window is not warm. Regardless, if
there is any rot, the windows have a 20 year guarantee.

If anyone can poke a hole in that reasoning, I'm all ears.

Thanks for the feedback, m R.

I can see how the track is vulnerable to dirt. OTOH, the windows I
have now are gliders, and I've only seen a need to clean the tracks
once in 3 years, so I don't think that's a deal-breaker.

We chose gliders because they suit the architecture of the house and
there didn't seem to be a compelling reason not to (except for the
difficulty getting a look at them, as documented here.) However, I
will double check the ratings, on your advice. Like the Andersens, the
Marvins seem to close nice and snug when the latches are flipped, so I
don't see a lot of potential for leaking, right off.

ccsikyr wrote:
Dealer's choice.

I don't doubt Andersen makes a decent product, but I'm skeptical of
vinyl in general.

Over time, after a beating from wind and rain, I think aluminum will
hold it's shape better than
vinyl. There are examples all over my neighborhood of vinyl windows
coming apart, not even five years after installation.
Granted, they aren't Andersen.

I'm open to persuasion, though.

I have 4ftx6ft vinyl gliders in my home, circa 1990, in the NE, no
problems, no whistles no cleaning[or even washing, or is that TMI] and
they open no problem. they were bought through a neighbor who sells them
and siding, i bought one more for an addition, and I shoulda bought all
of them there as they cost a fraction of the Andersons the architect
spec'd. I 'think' the guy has a Marvin sign up, but there aren't any
labels on the window that I have noticed

Ratings are what you go by, if im wrong ok but by the design of pulling
a window into the frame as casements do my limited research of air
infiltration ratings showed casements superior, in air infiltration. I
know my casements are still tight after years, and my sliding glass
doors, Anderson a bit loose now from constant opening. It is logical a
sliding seal will loose efectivness faster than one pulled tight. One
other rating of many of importance is CDF, condensing factor, my Pellas
condense, my Andersons dont, I researched this to late as Pella at a
Consumer Reports test article, is rated lower on Dual pane Low E argon
than Anderson. For windows depending on where you live there are
different types of E coatings, some optimise SHG for high heat areas
some reduce SHG, solar heat gain. Windows have alot of science behind
them to save energy. Hurd offers several types , good to look at what
they offer to see what is location important, they have high SHG and
lower SHG types. In Fla you want low SHG and VLT in Minnesota for
example you would want high SHG + VLT. There is always something new out
with glass to make utilities less of a burden, glass is not equal as
salesmen tell you. Google there is alot to read.

On the issue of durability, Consumer Reports, October 2000 rated
windows on durability, among other things, where

durability "indicates how well the windows performed after two weeks of
severe temperature fluctuations and intermittent spraying with water"

The only windows that were rated "excellent" were Marvin aluminum clad,
Pozzi aluminum clad, and Andersen Millenium (which evidently is the
Renewal line -- vinyl/wood composite)

Notes on almost all the other windows include "some parts warped or
loosened in durability tests". This includes Pella and Caradco
aluminum clad, Andersen and Weathershield vinyl clad, and all solid
vinyl windows except Weathershield, Alside, and Certainteed.

I'm a builder in Virginia and put Norco, a Jeld-Wen company, aluminum
clad glider in my house, also have Norco casements. We install
Anderson's, Marvin's what ever the buyer wants. The glider is a simple
but effective window design, that requires low maintenance (track
cleaning), but no moving parts to break (DH balances or Casement
cranks). I chose Norco, because I felt it's built as well as the big
boys, but is more affordable. Shelter System's in Manasas will sell
you Anderson, Norco, Marvin what ever you want. Call Brian at (703)
369-1552.

ccsikyr wrote:
On the issue of durability, Consumer Reports, October 2000 rated
windows on durability, among other things, where

durability "indicates how well the windows performed after two weeks of
severe temperature fluctuations and intermittent spraying with water"

I don't understand what that test equates to in the real world. Two
weeks is hardly a test for something meant to last decades. Consumer
Reports tests paints and deck stains for year(s) to see how they hold
up, and yet they test windows for two weeks? A ridiculous amount of
extrapolation points to a meaningless test.

What does severe temperature fluctuations mean exactly? I live in an
area where 0 degrees and 100 degrees are not uncommon - they never
happen in the same season, much less the same day.

What does intermittent spraying with water mean? Window manufacturers
subject their windows to water tests with hurricane force winds.

I think Consumer Reports is a great publication - a great service. But
unless you've edited out a lot of information in your synopsis, the
results are not relevant as the test is just bizarre.

R

Well, if two weeks was enough for some of the windows to warp or get
loose and others didn't, then it appears we can learn something from
the test.

ccsikyr wrote:
Well, if two weeks was enough for some of the windows to warp or get
loose and others didn't, then it appears we can learn something from
the test.

Not necessarily. It's a false positive (or negative) if the test is
flawed. Testing for something the system wasn't designed to handle
isn't testing the system.

Suppose I took a garden hose and sprayed the water up under your
shingles. The roof would leak. Does that say anything about the
shingles? I don't think it does.

R

A false positive is not the same thing as a flawed test. All test
statistics have statistical properties and when you pick a threshhold
to indicate positive, you are picking a probability you'll indicate
"positive" when in fact the true state of the world is "negative" -- a
false positive. OTOH, a "flawed test" simply doesn't provide
information about the subject of interest, like your absurd garden hose
example.

Consumer Reports is not going to provide us with any more detail than I
gave on the test. Beyond that description, you either trust them or
you don't, as you see fit. I tend to think there's actual information
in their ratings. They have a lot to lose if they construct a flawed
test. I don't recall seeing window companies objecting to the
evaluations when I googled "consumer reports and windows". They do
note in the article that window "makers participating in a program run
by the Insulated Glass Certification Council subject insulated glass to
tests that expose the glazing and its seals to heat, cold and water.
Glazing that passes three test segments earns a "CBA" mark, etched in
the corner of the glass." Sounds like that industry group evaluates
glass and seals using a method similar to Consumer Reports. Sounds
like you don't trust them. So be it. Take what you like and leave the
rest.

Cheers.

Andersen gliders do not seal any better than any others. If you go to
nfrc.org and check out the thermal performance for ANYONE's casement
windows, they will seal better than any slider/ glider.

Also, most glider/sliders wind up with water in the inside tracks some
time or other. If water gets in, so will air.

D4 wrote:
Andersen gliders do not seal any better than any others. If you go to
nfrc.org and check out the thermal performance for ANYONE's casement
windows, they will seal better than any slider/ glider.

Thermal performance, U-Value, and air infiltration are two different
animals. I was primarily talking about the window seal and air
infiltration. I just visited the NFRC site and didn't see any
information on air infiltration - just U-values. Where can I find that
information on that site?

R

ccsikyr wrote:
A false positive is not the same thing as a flawed test. All test
statistics have statistical properties and when you pick a threshhold
to indicate positive, you are picking a probability you'll indicate
"positive" when in fact the true state of the world is "negative" -- a
false positive. OTOH, a "flawed test" simply doesn't provide
information about the subject of interest, like your absurd garden hose
example.

It was meant to be absurd. It was meant to show that testing a system
for something it was not designed for is not testing the system. I
said that.

Consumer Reports is not going to provide us with any more detail than I
gave on the test.

Okay...I haven't read the report. You have. I'm not sure why a
testing procedure wouldn't have its specifications listed. Two week
duration. That's a specification. Intermittantly sprayed water is not
a specification - it's a very loose description.

Beyond that description, you either trust them or
you don't, as you see fit. I tend to think there's actual information
in their ratings.

Of course, but the question is, does the information have relevance for
what I need a window to do?

They have a lot to lose if they construct a flawed
test. I don't recall seeing window companies objecting to the
evaluations when I googled "consumer reports and windows". They do
note in the article that window "makers participating in a program run
by the Insulated Glass Certification Council subject insulated glass to
tests that expose the glazing and its seals to heat, cold and water.
Glazing that passes three test segments earns a "CBA" mark, etched in
the corner of the glass." Sounds like that industry group evaluates
glass and seals using a method similar to Consumer Reports. Sounds
like you don't trust them. So be it. Take what you like and leave the
rest.

I wrote: "I think Consumer Reports is a great publication - a great
service. But unless you've edited out a lot of information in your
synopsis, the results are not relevant as the test is just bizarre." I
don't see how that could possibly be construed to mean I don't trust
them.

I was merely asking what "severe temperature fluctuations" means. It
may mean 30 below zero to 150 above in an hour - I have no idea. Both
ends of that spectrum are meaningless to me in my climate. Windows are
designed for longevity, trying to force a test to have failures (how
else could you determine the winners and losers?) in two weeks means
something fairly extreme is going on. I'd like to know specifically
what the extremes are. I don't think it's really asking a lot if I am
to give credence to anyone's testing procedure. The "intermittent
spraying with water" also needs clarification. Spraying doesn't
necessarily indicate anything at all about the amount of water and the
pressure.

I don't take anything on blind faith, and I don't happen to feel that
CR is an unquestionable authority. I don't subscribe to CR, so this is
all I found in a quick Google:

"How to choose
Performance differences. Consumer Reports has found most windows do a
very good or excellent job at sealing out a fairly strong wind when the
outside thermometer registers 70° F. Only a handful do well at sealing
out a high wind when the outside temperature drops to zero. When it's
that cold, weather stripping and other components can stiffen or
shrink. Our tests have shown that aluminum frames are durable. But we
have found windows with frames made of vinyl- or aluminum-clad wood can
perform well, too.
Recommendations. If you're replacing windows, choose those that are
designed for your region's climate. Cooling costs predominate in
southern regions, so look for double glazing and a low-E coating. Give
first consideration to windows with a low solar-heat-gain coefficient.
The Department of Energy recommends that the number be 0.4 or lower."

There are specifics in that. 70 degrees vs. 0 degrees, for example.
I'm more interested in the 70 degrees as the 0 degrees is a lot rarer
around here. My personal experience also counts for something - at
least to me. If I hit an aluminum clad window frame with a bat, in any
weather, that dent will be there forever. If I hit a vinyl clad window
with a bat on a 70 degree day, it won't do much of anything, while on a
0 degree day the vinyl will almost certainly crack (don't hit vinyl
windows with bats in very cold weather).

R

I understand what you're saying.

I do think it's worthwhile to use a rule of thumb that the CR people
are not doing something absurd, based on their track record. Faith?
sure. Blind? no. Always correct? no. Do I sound like Don Rumsfeld?
you bet.

Thanks very much for your thoughts on windows.

I've beat the internet pretty hard and can't find much information on
air leakage by brand, let alone window type. According to the NFRC
site, the air leakage rating is currently optional on their stickers.

It is interesting, though, that Marvin double hungs and casements, for
example, have the same R-factor (2.7) and the sliders have a lower
R-factor (2.33). There could be things other than air infiltration at
work, of course.

Thanks. I have found a few contractors that will install whatever
brand I'm interested in. The rub is, where can I see one before I buy
15 of them? With the exception of Marvin and Weathershield, there
don't seem to be any in the area showrooms.

My research from online and factory brochures showed casements superior
in air infiltration to sliders and double hung, only fixed units can
surpass a casement, as I previously noted you pull a casement into its
weather stripping, sliders also wear the gasket, test are on new units.
For high wind areas casements cant be beat, and considering slide type
seals that wear out and the fact that 50% of heat loss can be air
infiltration in old units casements win every time

m R,

If you have any data on that left over from your research, I think it
would benefit a lot of window shoppers to post it. In my experience,
it's hard to find data on air leakage. The NFRC has a standardized
rating, but I believe it's optional to report it.

I think there's some merit, qualitatively, to the argument you're
making. But ultimately, people put different weights on different
factors, so the magnitude of the difference is key here. As I noted,
the R-factor data from Marvin is *suggestive* on this point, but not a
pure measure of leakage.

Cheers

ccskr I emailed you, and will look, but alot of this I got on factory
Pella Anderson and Hurd brochures, alot of company sites info online I
cant access because of weby tvs limited usefullness . All major window
companies have every rating for every window they make, for anderson it
is hundreds of windows.

Well, anything you've got handy. Don't go doing all the research all
over again!
I keep beating on google, thinking surely there's a website where these
air leakage and other ratings are tabulated for the major window guys,
but I don't see anything like that.

Thanks again.

Does your Co detector have a digital read out and record peak readings
from 1ppm, if not get one 35$. Could it be an Ng leak, there are dual
types of senors for 50$. Get a pro to fix it if you can`t.

I have to get all that research back for a job but it will take time.
Andersons and pellas sites have it im sure somewhere.