A walk through Edmonton’s historic neighborhoods will reveal special window charm. Windows in many distinct homes contain wavy glass, it’s something quite special. Floating molten glass over a bed of liquid tin is today’s glass making process, which results in truly flat and mirror-like sheets of glass of a fine quality without waves, bubbles, or distortions. Originally, glass was made differently. Prior to the industrial revolution, most glass was hand-drawn, machine-drawn, or blown as cylinder glass. The difference between the cold clinical light seen through modern float glass, and a warm refracted light seen through early Victorian cylinder glass is profound.
At Perma Seal Windows & Doors we think this building material gives a peek at the past.
Owners of character homes in Edmonton who appreciated the original charm of Wavy Glass can read on to see how to look and tell it apart from more modern glass types, and what can be done to maintain, replicate, or replace broken panes with original wavy glass to remain true to history.
What is wavy Glass? What makes it special? Where do I find it?
Wavy glass, aka glass of earlier periods-period glass, isn’t perfect or smooth like modern flat glass. It has waves, bubbles, inclusions-flaws that occurred naturally as glass was handmade, blown or drawn into a cylinder, or machine-drawn to provide a soft, wavy or rippled effect. Great news for artisans, homeowners, and restoration experts who view flat modern glass as a barrier to wind as opposed to gentle, wavy glass that looks more real and alive, bending light softly in a way to provide a nostalgic, deeper, inviting, and more interesting view than modern float glass can. Perma Seal has this glass in stock.
Why is the glass important in historic homes?
In many of Edmonton’s older heritage neighborhoods, keeping windows in good shape isn’t just about how they work; it’s also about honoring the history of structures, and maintaining methods used to make them in the time. Wavy glass help maintain original charm, and the design intent of any heritage property, whether it is a “Craftsman”, “Victorian”, or a Four Square two storey gem in Old Strathcona.
The proper glass in original windows is in line with heritage requirements and looks more interesting, a perfect fit for your historic home or building. Original wavy glass is more appealing to buyers who care about originality, history and maintaining historic resources true to their period.
How do I identify if I have wavy glass in my home?
Look at the reflections; stand at an angle and look through, if reflections are distorted, curved, or uneven, chances are you have wavy glass in your windows. Other ways to check for wavy glass-run your fingers lightly over the surface. Unevenness is a sign of wavy glass. Looking through the glass in sunlight will reveal ripples, dips, waviness-none of these are considered flaws, rather, “beauty marks” on glass that softens light passing through!
If you’re still not sure, ask the experts at Perma Seal, we can explain if your windows are glazed with original wavy glass, or a newer glass replacement.
Can wavy glass be fixed?
No glass cannot be fixed, but it can be saved. While looking through a break in a glass pane is not ideal or even desirable, it is acceptable in the realm of heritage and professional restoration. Glass panes still whole, but loose, scratched or covered in paint are useable. Wavy glass means original character with its beautiful undulations in your historic home.
What if the glass is broken?
The beauty and character of wavy glass is desirable to maintenance of original aesthetics and the character of a historic home. Wavy glass is still made today by artisans; modern versions of wavy glass still provide the same wavy look but using more modern glass drawing techniques. Perfectly smooth is for peanut butter, hand cream, and modern glass not beautiful, wavy glass.
A quick look at glass types…
Cylinder glass: hand blown from molten glass was scored at red hot stage to allow the cylinder on reheating to flap open then rolled to give a mostly flat piece that was then cooled slowly to remove internal stresses and toughen the glass panel.
Hand drawn glass is made with a hot metal “bait” dipped into a vat (crucible) of molten glass, then slowly drawn upwards by hand to form a sheet of glass. The method offered fewer imperfections than was achievable with the cylinder-glass technique, upward draw and gravity worked to provide the characteristic waviness of Wavy Glass.
Before the industrial revolution traversed the oceans, the development of machines and better process allowed drawn glass to be made in greater quantities and larger sheets. Drawn glass
uses lift and gravity to form glass panels. The process of machine-drawn glass is similar but produced better glass quality. The process involved molten glass drawn from a glass furnace’s working end, a boat-shaped slotted block made of refractory material is pushed into the molten glass, resulting in hot extruded glass rising through a slot to be grasped by an iron bait. Glass cools to adhere to the bait and is pulled upward slowly between water-cooled tubes, the sheet toughened by the process. The glass sheet reached the top of the machine to be cut by automatic cutters. The outcast is then reheated and flattened with rollers, and a glass sheet
with soft undulations and interesting marking is ready for sale.
For decades Perma Seal has restored historic windows and doors. The use of Wavy glass for proper historic restoration is a lot like using the right tool for the job. Using modern glass in a heritage window may in fact fill the hole but the action is not original, authentic, nor is that attuned to the preservation of culture or history. We at Perma Seal breathe new life into once beautiful old things.
Our work is done out of respect for beginnings-the heritage and culture offered by the first settlers and First Nations who came here first-respect for heritage is our mission, and we do so one wavy pane of glass at a time. Let Perma Seal be your guide for historic repairs, reconstitution, or replica wooden sash, muntin bars, and trim to match original architectural profiles with the same wood species and grain, as they were originally.
How can Perma Seal assist your continued enjoyment of the beautiful historic fenestration in your home?
We simply make sure every detail is right, ensuring our repair techniques last a long time. Many historic windows have been in place more than 100 years already…and they still can be fixed. No other window made can make that claim! Another hundred years is the goal when we use the right materials-old growth fir. Joinery remains the same as it was 100 years ago, open and/or closed mortise joint connections, and the Dutchman lap are age old time-tested techniques used then and are still used today, often with the same hand tool.
The process assures all work we do will honor the workmanship and detail of turn of the century craftsman
who made these windows 100 years or more ago. So, whether you need help finding hardware, wavy glass, sash rope and counterbalance weights…little things that help your historic windows with wavy glass, ropes, pulleys and weights look and feel real, and true to the home’s construction…expect respect for things of history here.
Privacy Glass in Older Homes
If privacy is a concern due to large, single-pane heritage windows, wavy glass helps to distort inward visibility slightly but can be seen out through. Our mission is to keep historic homes original and authentic to the period they were crafted in. Options that mate with architectural requirements for antique glass are frosted, reeded, or sandblasted, and special art-glass made by artisans do let you feel safe and private, without losing the history of the home.
Why is modern (float) glass may not be the best choice for window restoration?
Float glass came to prominence in the late 1950’s. Perma Seal one of the first to use float glass in manufacturing insulating glass units in 1964. Float-glass is the most common glass product used today. The namesake “float” comes from the process of manufacturing the glass, where molten glass is floated on top of a bed of molten tin to make modern glass sheet ultra smooth. Clarity is driven by the glass “recipe”. It’s not hard to see glass quality from its edge. Looking at the edge of a piece of glass with higher iron content (used for strength) looks green. Higher quality, clearer glass requires sacrificing some strength for clarity, so, glass with low iron content
is dramatically clearer, just like its edge.
Replacing wavy glass with modern float glass makes a heritage window look odd, even if all else is fixed. Use ‘float’ glass as more strength and less clarity is necessary, whereas areas of importance to the home’s original character should use ‘wavy, restoration glass to maintain designation requirements that exist to keep heritage properties in original design intent while respecting original character. Keeping wavy glass original is sometimes mandatory to government funding for work.
WINDOWS AND DOORS THAT LAST FOREVER
We have worked on historic homes all over. As far as Edmonton’s heritage goes, from the tiny lake cottage built in 1910, to Grande homes commissioned built by neighborhood developers at the turn of the 20th century, they all have similar needs. Use the same material the artifact was made from to correct rot, missing parts, and pieces. Some people can’t chew gum and walk at the same time.
At Perma Seal we satisfy modern efficiency expectations while protecting local history at the same time. Come look at a 100-year-old window fully restored with wavy glass and see yourself how we at Perma Seal are true Stewards of our Heritage. We do good work…we really do serve history well.
What makes us different?
We research the history of older homes and window types, our access to wavy glass, the knowledge and tools we complete historic work with, our attitude working with heritage in Edmonton, access to important products of the period-wavy glass and old growth fir, the
knowledge and experience accumulated during hundreds of projects over decades of doing this work are a few.
Then you can be assured we will encourage respect for heritage rules, guidelines, and laws that govern repair and restoration of historic places in Canada, and we offer clear, polite and attentive communications from start to finish and throughout your heritage project. Four single syllable words best describe our offerings… We do great work!
Every project is treated with attention to details, skill, and appreciation for Edmonton’s architectural history, whether fixing one window or the whole house.
Final Thoughts
Wavy period glass softens sunlight, brings movement to reflection, and silently tells the story of a home’s age and character. Restoration of these old windows creates beautiful heritage artifacts that keep your home structurally sound, respectful of culture and visually correct to its
original design. Reach out for help, rather than let beautiful heritage creations fail from inattention. We assist homeowners, heritage property managers, and historic institutions with heritage needs. Wood, glass, and plenty of free advice are all available here. For decades we continue breathing new life into Edmonton’s treasures!
To learn more or schedule a consultation at www.permasealwindows.com
Good work done every time!
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