Vinyl Deck Membrane Essentials – Taylor Construction

Vinyl deck membranes are beautiful to look at, comfortable to walk on, and require minimal maintenance.

If you look around Calgary you will see that they are being installed on a large number of balconies on single family and multi-family buildings.

As wonderful as they are, the time comes when they must be replaced.

It is important that these replacements are completed with the membrane being properly adhered and detailed into the surrounding structure. Failure to complete proper installation and detailing will often result in premature failure of the vinyl membrane or worse, water entry into the building structure.

Required Aspects of Vinyl Deck Membrane Replacements

We have completed vinyl deck replacements on hundreds of balconies in the Calgary area in the past decade. We know how to properly install and detail vinyl deck membranes and we have seen first hand the results of improper installations and detailing.

When you are getting your vinyl deck membranes replaced make sure you look out for the following:

1. Proper Substrate

When installing membranes over wood structures ensure plywood sheathing is present and is in good condition. OSB sheathing or plywood in poor condition will not allow the membrane to properly adhere and can result in the membrane coming loose over time.

When planning for a vinyl membrane replacement, ensure you budget for the cost to replace the sheathing as in many cases it will be required.

2. Potential Structural Moisture Damage

If the original membrane was poorly installed or detailed, or had tears or holes in it, there is likely some degree of moisture damage to the underlying wood substrate. It is very difficult to determine the full extent of damages and required repairs without first removing the membrane.

3. Vinyl Deck Membranes Over Concrete – Don’t do it!

We have observed several locations where vinyl deck membranes have been applied on main level concrete slabs for unit patios. Whether these slabs are just on the soil substrate or over a parade below, moisture movement through the concrete from below will often cause the membrane to come loose from the substrate.

4. Proper Detailing into surrounding walls, roofs, and doors

One of the most important aspects of any building enclosure is to ensure that all of the components that are controlling and preventing water entry into the building structure are properly connected with each other. This is one area that requires particular attention with vinyl deck membrane replacements.

Most vinyl membranes have building exterior walls surrounding them and some even have roof surfaces right next to them as well.

Some installers will just cut the existing membrane out right at the very edge of the exposed membrane, install the new membrane to the same point and then apply a bead of sealant at the joint between the new vinyl membrane and the cladding or door above, or the adjacent roofing system. This will often restrict drainage of the adjacent system and can result in water being directed under the new vinyl membrane.

It is very important that steps are taken to properly detail vinyl deck membranes into the surrounding structures to ensure proper drainage can be maintained and to keep any precipitation outboard of the new vinyl membrane.

In order to do this, detailing often includes:

Removing the bottom several inches of cladding to allow the vinyl membrane to extend 8” up the wall and to lap up behind the wall weather barrier wrap.
Removing any doors, wrapping the membrane fully into the door opening, and then reinstalling the doors.
Ensuring any connections between vinyl deck membranes and roofing are detailed to allow for future roofing replacement without disturbing the vinyl membrane.

5. Plan for the next membrane replacement in another 15 years

When replacing a vinyl deck membrane it is important to take thought as to how the membrane may be able to be replaced easier the next time (in another 10-15 years or possibly a bit longer).

Provisions that can be looked at to allow less work to properly tie in the membrane the next time can include:

Removable battens at the base of the wall so cladding will not need to be removed to properly detail the next membrane.
A drip flashing at the base of the wall with a minimum 4” clearance above the deck surface to direct all water from above the flashing outwards. This will also allow future membranes to be installed and sealed tight to the underside of the flashing with no risk of water entry from above.

As stated above, we have replaced hundreds of vinyl deck membranes. We would also like to help you with your next vinyl deck membrane replacement project. Please reach out to us so we can see how we can best help you.