Harvey Window Manufacturing Facility Tour

By Todd Fratzel on Windows

Harvey Building ProductsHarvey Building Products Manufacturing

Today I had the pleasure of taking a tour of Harvey Building Products Londonderry NH manufacturing facility. The new state-of-the-art manufacturing facility houses over 300,000 sq. ft. of window, door and sunroom manufacturing. At this particular facility they manufacture both vinyl and wood clad windows along with Therma-Tru doors and the Harvey line of sunrooms and storm doors.

I was very impressed with then entire operation and how efficient and flexible the facility is. Two of the more impressive parts of the tour for me was the window testing facility and the actual window pane assembly operation. The engineer in myself found both of these aspects extremely interesting and useful.

Harvey Window Wind and Water TestingWindow Testing Facility

The Harvey facility includes a state-of-the-art testing operation that allows them to test variations of the window design and manufacturing process in order to improve the performance of thier windows. Today I witnessed two tests on a new construction vinyl window for both wind and water infiltration.

It’s hard to see in the photo but on the other side of that grey frame there is a window installed in a 2×6 wood framed opening. That window and frame are sealed up against the glass wall which allows engineers to apply vacuum pressure and water against the window. Trust me when I say this piece of equipment is very impressive to see.

The test that I witnessed applied a simulated wind speed of 155 MPH in addition to water. You wouldn’t believe the deflection and deformation one of these windows can withstand under those kind of conditions. Not only did the window NOT fail but very little water even entered through and around the window. The window was bulging out of plane more than 2 inches and looked like it should just explode, however it held together and went back to it’s normal shape once the loading was removed.

I certainly have a whole new respect for the structural integrity and strength of these windows. I’m going to go out on a limb and say that I’m fairly certain that a wood window would never be able to withstand that type of test. I say this because wood does not have the same flexibility and ductility as vinyl. Regardless it was very impressive to see and certainly shows me that Harvey takes testing and performance very serious.

Window Pane Assembly

The other part of the tour that I found really fascinating was how double pane and triple pane windows are manufactured. The whole process begins with a very expensive computer operated glass cutting machine that optimizes how many pieces of glass can be cut from a single piece of stock glass. The glass cutting machine is able to cut any shape from a circle to an elipse to a plain rectangle.  After the glass is cut they manufacture metal spacers that hold the multiple pieces of glass apart to create the air space. They also create architectural simulated glass dividers that are installed in the air space.

Once the spacers are built an amazing machine takes the pieces of glass and creates a sandwich (glass-divider-glass or glass-divider-glass-divider-glass). Next the sandwich of glass is moved into an over where it is compressed and heated up to seal the metal spacer and a butyl gasket. The final step is to pump in either argon or krypton gas between the layers of glass. The gas improves the thermal performance of the window pane.

Reflections From My Tour

I could go on and on about many other cool things I saw today on my tour. But what stuck with me most after visiting this facility today was how technical window manufacturing has become. I was so impressed with all the technology that’s being used to build high performance energy saving windows. Over the years I’ve heard so many people say they don’t like vinyl windows and vinyl windows are cheap. But the reality is vinyl windows are manufactured with such great technologies that they truly do deserve your consideration the next time you buy windows for your home. My tour today also reinforced faith in their quality products. We use Harvey windows in all the houses we build for two reasons: competitive pricing and superior quality.

About the author

Todd Fratzel

I'm full time builder for a large construction company in New Hampshire. I run their design-build division that specializes in custom homes, commercial design-build projects and sub-divisions. I'm also a licensed civil and structural engineer with extensive experience in civil and structural design and home construction. My hope is that I can share my experience in the home construction, home improvement and home renovation profession with other builders and home owners. I'm also the Editor-in-Chief and Founder of Tool Box Buzz. Please feel free to contact me if you have any questions, suggestions or you'd like to inquire about advertising on this site.

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  1. philip says:

    I worked in research at a university on wind loads on glass. We had a very similar device that we could modify to fit different dimensionsed glass. But we would test to failure, so you are sitting there watching the glass and waiting as the vaccuum increased, then all the sudden you have an explosion as the glass fractures! Everything we worked with was tempered and had vinyl so it did not fall out much but still it was not like a small crack starts then propogates but everything at once failed.

    • Todd says:

      @ philip – Very cool stuff! I was really impressed with the device and how useful it is for testing lots of different window configurations.

  2. Don Kaufman says:

    We purchased a total of (7) Harvey replacement windows recently and had to send (5) of them back so far because the glass was dirty on the inside or there were scratches on the glass. Very dissapointed with your quality and would not recommend your brand to anyone.

    • Todd says:

      Don – Sorry to hear about your bad experience. I do not represent Harvey, I only speak from my experiences with them. I’ve always had fantastic experiences with them and when something goes wrong they take care of it right away.

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