How to Install Fullback Insulated Vinyl Siding

January 11, 2019


Step by step installation overview covering corners, windows, starter strips, and backer blocks for wall penetrations


Begin insulation with corner posts. Fullback EasyPosts® are about four foot in length and not only do they insulate, but they square and shim the job.

EasyPosts can be cut with any thin-bladed knife or a circular saw. EasyPosts allow for the base thickness of Fullback siding insulation and are required for proper installation.


Installation steps:

  • Insert EasyPosts plus outside corners into the vinyl corner post.
  • With EasyPost plus inserted, install the corner post per the vinyl manufacturers instructions.
  • If using a manufactured inside corner, an EasyPost plus for inside corners is also available. Insert inside EasyPost plus corner behind the vinyl inside corner.
  • Nail through the vinyl nailing flange.


J-channels for windows, doors, and trim work

In order for the j-channel to properly receive this thickness of both the vinyl and the insulation, a 1-1/8 inch j-channel is required for Fullback and a 1-1/4 inch j-channel is required for Fullback 125.

If the distributor doesn't stock the appropriate j-channel, the distributor can order easy shim, which will help the space the j-channel away from the base of the wall. These shims can be installed under the standard j-channel. This will allow the Fullback insulation to be installed next to the shim and the siding can fit into the standard siding trim pocket.


Starter strip:

Begin with the easy start starter strip that accommodates the thickness of the Fullback insulation.

  • First, snap a chalk line to establish the wall line according to the manufacturer's specifications.
  • If using a starter adaptor, insert the groove of the starter adaptor over the outer edge of the easy start starter strip, making sure the back of the starter adaptor is flush against the nailing face of the starter.
  • Second, allow a quarter inch space between the starter strips and adjoining siding accessories to allow for expansion and contraction. For best results, alternate nailing high and low in slots provided.
  • Attach the siding panel to the starter strip.
  • Then before securing the siding to the wall, drop a piece of Fullback insulation behind the siding. Do not nail the foam to the wall first.
  • Fully seat the remaining Fullback foam panels in the first vinyl course and butt the foam edges tightly together. Three full pieces of Fullback will support the length of one siding panel.
  • Move the siding panel fully into its final position and nail it to the wall through the vinyl hem and foam.


Nailing and panel installation details

Remember, this vinyl siding is designed to be hung and supported by these siding nails. the don't wanna nail them to tight. Now to check it, the can move this panel horizontally back and forth for free movement.

  • To ensure flat, tight seams, be sure to install the Fullback behind each siding lap joint.
  • Butt the foam panels tightly together and tight to the corner post and window lineal.
  • Cut the siding to fit the area to be covered.
  • Attach it to the siding panel below.
  • Move it into position against the Fullback.
  • Nail through the nail hem and foam according to the vinyl siding manufacturers instructions. Make sure the distance between the top of the vinyl panels nailing hem and the Fullback panels but above the hem are of equal distance along the panel before nailing.


Installing around windows

There are several ways to apply vinyl siding under windows. the may wanna just continue with ther current technique. But there are some situations that may require some modifications.

Well for example, due to the cut height of the vinyl panel for the top course or under windows, the may need to nail a three quarter inch j-channel inside the j-channel the are using to securely fasten the panel. Sometimes the may even use a utility trim inside the j-channel depending on where the vinyl panel profile is cut. To install Fullback beneath a window or gable, measure the opening to be filled or covered with Fullback. Cut the Fullback to fill the opening.

Insert it into the space to be filled. Then cut the siding to size and shape. Install the siding and nail it according to the manufacturer's instructions. Now in cases where the distance between the vinyl siding trim pieces is very close, nail the trim pieces as the move up the wall with the Fullback and vinyl siding. This allows the to pull out the trim pieces enough to tuck in the vinyl siding. In cutting around penetrations, use a mounting block where possible.

Fullback is all about superior design, ease of installation, product support, and field tested performance. the know, a job with Fullback is like no other vinyl siding job. There is no other product on the market that is as effective in closing sales and increasing referrals than Fullback. Well my name is Matt Fox and on behalf of all of us at Progressive Foam, thanks for joining us.


—This video is from Progressive Foam Technologies, one of ProTradeCraft's advertisers. Founded in 1992, Progressive Foam invented and brought insulated vinyl siding to the marketplace and have since diversified to add siding insulation products that can be paired with fiber cement, engineered wood, steel, and others. See all of Progressive Foam Technology's videos.