Maybe you are aware of the fact the majority of homeowners are going to choose vinyl siding when updating their home exterior. There area a few reasons behind their decision:

  • vinyl siding never requires painting
  • it resists rot and insects
  • it’s very simple to install for DIY-ers and…
  • it’s also quite affordable

When it comes to using it in new constructions, it’s generally installed with a moisture barrier and rigid foam insulation over wood wall sheathing.

If you’d consider installing vinyl over old wood siding you don’t have to worry about removing wood first, you just might need to adjust the door frames and windows to compensate for that extra wall thickness.

Existing wood siding must be in serviceable condition

Existing wood siding must be in serviceable condition

Existing wood siding must be in serviceable condition

What that means is the existing wood siding cannot be falling apart, it needs to be properly fastened to the wall studs or sheathing, there should be no mold on its surfaces and if there are any bad, rotten boards, then they’re going to have to be replaced.

On top of that, you’ll also need to remove any trims like corners, wood and / or door trim so the only thing left are siding boards.

Furring Strips if Necessary

For your vinyl siding to be properly installed it needs to be applied against a flat surface. If your existing wood siding boards are either lapped or beveled, you’re going to need to use vertical furring strips spreader sixteen inches apart on centers. The space created between the strips should be filled with rigid foam board which is the same thickness as the strips.

Moisture Protection


House wrap under the vinyl siding

If there is no moisture protective membrane installed beneath the wood siding, one will have to applied before vinyl siding installation.

Polyethylene or other house wrapping material with similar characteristics tacked over the rigid foam and broad headed nails will do the job.

All of the house wrap seams must be sealed with a tape designed for this purpose.

Frame Width Adjustment

In order to accommodate a thicker wall, you’re going to have to adjust the door and window frames. For this, you need to assess the size of the vinyl panels, that of the existing wall and then add the thickness of any foam insulation.

To extend the depth of the door frames, windows any any other openings, you should make use of brick molding to accommodate the new vinyl siding panels.


Vinyl siding trim boxes

Proper flashing / trim boxes should be installed at any wall penetrations such as electrical receptacles, gas pipes, water faucets, remote water meters, etc. Those are available at a variety of colors to mach your siding.

Starter Strips

For a proper vinyl installation, starter strips are essential. Around the bottom of your home, make sure to snap a level chalk line approximately 1” above the bottom edge of the old wood siding. This is where a starter strip responsible for holding the bottom of the 1st row of vinyl siding should be secured. At the house corners, you should leave about a quarter of an inch gap and then proceed with driving nails in the middle of the nailing slots.

Utility Trim and J-Channel Installation

The vinyl siding panels are held in place by the j-channel strips and the utility trim has it place beneath the windows and as a strip at a top of all walls / right under the soffit. When it comes to the fastenings, keep in mind that all of them need to have room for expansion on both ends and nails have to be carefully placed in the middle of the nailing slots.

Snap Panels

Vinyl panels should be installed one strip at a time starting from a back corner of your property. To go about this, you’ll need to consider snapping the bottom of the 1st panel tightly into the starter strip and then push its end into the J-channel.

To ensure it’s level, you’re going to have to use a level and then use board headed nails in order to fasten it. Next, panels need to be overlapped from the front by approximately four inches. At each opening, corner or end, you need to also leave a gap of a quarter of an inch.

Differentiate Seams

Starting a second row is easy and you need to use a shorter section of a full panel to do that so the seams of each row are not aligned. Use a power saw, a utility knife or any other tool you can in order to cut the panels to the required size so they fit around the windows, doors and other openings. To ensure the panels are level, each row needs to be carefully checked with the level.

Use Lugs at Tops and Windows

Lastly, the panels should be fastened at the wall top and under windows by using a snap lock punch. To fit the punch lugs and the space the panel should then be carefully cut lengthwise and the lugs pushed into the utility trim.

It wasn’t that hard, wasn’t it? This video below shows the entire process of vinyl siding installation, although, it isn’t over the wood siding. However, except for a few items at the beginning of this manual everything else in this video applies. Enjoy!