I do several phase inspection a year. I will look at installations of the various components of the home and perform in essence quality control.

During a recent phase inspection of a new construction I saw the contractor installed the windows without using the manufacturer’s pre-punched slots for the fasteners. Depending on the environment of the home this may have an effect on the performance of the window and shows that the windows were not installed per manufacturer’s recommendations.

Now this will vary a bit from manufacturer whether it will void a warranty. I spoke with a technical representative from one of the prominent window manufacturers here in Washington State and their position is they do not warrant the installation, just the windows.

Vinyl will move in relation to wide temperature fluctuations.  If this is not accounted for it will put stress on the frame and possibly on the sealant used around the glass.  Over time this can lead deformation during certain times of the year and in extreme cases cause damage to the flange or welds. Vinyl windows have pre-punched slots to account for this movement. Fastening in any other portion may damage the windows and limit rights under the warranty by some manufacturers.

In addition you do not want to overdrive the fasteners. This may fracture or unduly deform the mounting flange.

For this manufacturer here is their installation guide.

http://www.cascadewindows.com/sites/default/files/installation-instructions.pdf

From the guide-

Apply one fastener through a pre-punched hole in the nailing fin at the side of the frame, approximately 3-4” below an upper corner of the unit – to “lock” the unit in place. Use fasteners that will penetrate into the stud at least 1”.

Ensure unit is SQUARE, PLUMB, AND LEVEL, with FULL support under sill.

Apply another fastener through the nailing fin at the opposite diagonal (lower) corner of the unit.

Verify the unit is still SQUARE, PLUMB AND LEVEL, that unit operates smoothly, and that operable sash are sitting square in their openings.

Continue fastening window, using every other pre-punched hole in the nailing fin.

As you can see this installation did not meet the recommendation and should be corrected.

“The learning and knowledge that we have, is, at the most, but little compared with that of which we are ignorant.”

Plato

NCW Home Inspections, LLC  is a Licensed Washington State Home Inspection service located in Wenatchee Washington serving Chelan County, Douglas County, Kittitas County, Okanogan County and Grant County Washington and the cities of Wenatchee, Leavenworth, Cashmere, Oroville, Cle Elum, East Wenatchee, Quincy and many more…  

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