Replacement Window Installation

Get Your Money's Worth:

At LONG LIFE we believe that the replacement window installation is as important as the window product itself. If your new windows are not installed properly, than you are not getting your money's worth and you may run into problems in the future. As a consumer you need to be aware of the various methods of window retrofit or replacement. Below we will review the three most common replacement window installation practices used by replacement window contractors in Vancouver and the lower mainland, Piggy-Backing, Full Replacement using a Rebate Flange and Full Replacement using Nail Flange. Obviously, the cost, quality and performance for these three methods are not equal. In our wet climate it is imperative that special attention is paid to installation methods and installation materials (caulking, sealing foam, flashing's etc...)

PiggyBacking:

This method is fairly simple to understand, and is more typically used when replacing aluminum framed windows. The installer simple removes the glass, the sliding or opening Sash and any dividers or Mullions. Then he places the new window frame on top of the remaining aluminum frame, hence the name PiggyBacking. The new window, is supplied with a Rebate Flange on the outside which covers or trims the exterior and is caulked to the old frame. The window is screwed into place through it's frame and into the rough opening. The interior should then foamed around the gap created between the new frame and the drywall and sills. A wood trim is then required to cover the foamed gap. Ideally a pan flashing will be installed along the sill.

Advantages of this method

Quicker and easier installation.
Doesn't disrupt the integrity of the building envelope.

Disadvantages of this method

Leaves a portion of the cold metal frame buried in the wall.
It makes it difficult to properly support the weight of the new window.
New windows will be made smaller to fit over the existing frame.
Is very dependant on caulking for the water seal.
Does not meet The National Building Code standards.

Full Replacement (using a Rebate Flange):

In this method the entire metal frame is removed except for the Nail-Flange which is cut off from the outside without damaging the exterior siding or stucco. Prior to the installation of the new window a Pan-Flashing may be added on the sill. If the window is not directly protected by an overhang the head should be flashed. Well equipped installers will have a portable bending-machine which will allow them to custom fabricate flashing's. The new window is then installed and screwed into place through the frame and special expanding foam is utilized to ensure that the window is air tight in the rough opening. Alternatively a foam rod is put in place around the interior of the window to insulate and prevent drafts. Generally, high quality caulking will be used on the interior and exterior as a final step.

Advantages of this method

A relative ease of installation that doesn't damage the exterior.
Allows for proper shimming and support of the new window.
Not dependant on caulking for water and air tightness.
Allows for installation of flashing's.

Disadvantages of this method

Window will be slightly smaller than the existing window but larger than in the Piggy-Backing method.
Installation of flashing's is heavily dependant on the abilities and equipment of the installer.
Installation requires more time and is therefore more costly.

Full Removal (using a Nail Flange):

This installation practice is the most involved but is also the closest to current new construction practices. The siding or stucco of the home is cut back to allow for the removal of the entire old window including it's nail-flange. The interior drywall on the window jamb may also be removed. The new window is now installed and fastened with a nail-flange and can be properly flashed and sealed. Expanding foam should still be utilized to minimize air leakage. Finally, exterior wood trims will have to be installed around the window or stucco will have to be patched. If the interior drywall was removed, new wood sills, liners and casings will have to be installed. Some caulking will be required on the exterior.

Advantages of this method

Most likely to resist weather related problems.
The windows will be the same size as the existing windows.
Exterior and interior trims can modernize the home and add to it's appearance.

Disadvantages of this method

It requires disturbing the exterior siding or stucco.
The installers need to be more highly qualified.
Is the most time consuming and is the most costly.

“You Get What You Pay For”:

Contractors generally employ variations of these methods. Some genuinely strive to provide the very best workmanship, others emphasize speed and low cost.

There is ongoing testing to improve window installation methods within the industry and we have access to experts across the country. Please feel free to e-mail us with any question.