Repairing warped vinyl siding not an option

Hey there, time traveller!
This article was published 15/08/2004 (7748 days ago), so information in it may no longer be current.

QUESTION — Your article in the Winnipeg Free Press about painting stucco raised my curiosity about a different problem we are having.

We have vinyl siding and unfortunately, the barbecue was placed a bit too close and it warped the siding. It is not too big an area, about two inches wide and high, but it does not look good.

Is there a way to repair the siding without replacing it? I was thinking of a hair dryer or other similar heat source and then trying to flatten it out. Then I thought you have probably come across this problem before and may have a fix.

Any advice would be appreciated. Thanks, and I look forward to hearing from you soon.

— Rick McCoo, e-mail

ANSWER — The first thing to do is move the barbecue! I would be more concerned with the chance of this happening again in the future and causing a fire that would spread well beyond a little damaged siding. Vinyl siding is highly combustible and could catch fire if the heat or flames from cooking dinner go too high.

I have indeed seen melted siding like this on a few occasions during home inspections and always warn my clients and the current homeowners, if they are present, of the danger.

As far as repair to the siding, it is unlikely, unless the damage is very minimal. If the damage is only superficial, and the integrity of the siding is intact, it may be salvageable. In this case, I would not try to fix the problem, but leave things be. The heat from the barbecue has already damaged the vinyl and you may only damage it more by heating it further when trying to fix it.

Leaving the siding in the current condition will only be a possibility if the siding is still interlocked with the adjacent strips and has no holes or gaps due to the warping.

Exterior siding on a home, whether it is vinyl, wood, brick veneer, stucco or other material, provides much more of a function than most homeowners realize. Most people think that the siding is mainly an esthetic wall covering to hide the unsightly wall sheathing beneath, but this is not the case. Siding is the outermost layer of the “building envelope” and the first defence against moisture intrusion. The exterior wall system is a major component of the building envelope and must prevent moisture from entering, while allowing trapped moisture to escape. This may seem like a contradiction, but in reality this is how a proper outside wall works.

Exterior siding should prevent the majority of moisture from rain and snow from getting into the wall behind, but some may get through. For this reason, building paper or housewrap is installed behind the siding to prevent this moisture from damaging the wall sheathing beneath. If a small amount of water gets through the siding, it should run down the outer surface of this thin membrane layer and drain to the exterior. This is why vinyl siding will have small holes or slits in the bottom of the individual sheets, to allow this moisture to drain. Brick veneer and stucco should be properly installed with a slight gap between the material and the building paper as well as gaps or weep holes at the bottom to allow moisture to drain, as well.

This drainage is critical, not only to allow rain that gets behind the siding to drain, but also to let moisture entering the wall cavity from inside the home escape. In the heating season, warm moist air from the home may force its way into the cooler building envelope through small holes or gaps in the interior wall coverings and air-vapour barrier. If the exterior siding is tightly sealed, this moisture will be trapped in the wall cavity, causing moisture damage, rot and mould growth. If the siding is properly installed, this water vapour should escape through the small holes at the bottom of the interlocked vinyl siding strips.

If the vinyl siding on your home is damaged so that it may allow excess moisture to get behind, or the weep holes have melted closed, it must be replaced. This may be difficult to accomplish, if the damage is in the middle of the wall section or if the siding is more than a few years old.

This is probably the biggest drawback to this style of siding. Vinyl siding is interlocking and is installed from the bottom of the wall to the top. A large area of siding may have to be removed and later reinstalled after replacement of the melted strips. If the siding is older, it may be very difficult to find an exact replacement that will match your home properly. If you are lucky, you may find extra pieces of siding stored in the garage or be able to remove siding installed below a deck or other covered area, where replacement will be less noticeable.

If none of these options is possible, replacement of the siding on the entire wall containing the damaged vinyl may be the only viable option. In this scenario, you may even decide upon changing the siding material to brick or stucco, which is essentially non-combustible, and will allow you to barbecue in relative safety.

Ari Marantz is the owner of Trained Eye Home Inspection Ltd. and the Vice President of the Canadian Association of Home & Property Inspectors (www.cahi.mb.ca). Questions can be e-mailed or sent to: Ask The Inspector, P. O. Box 69021, #110-2025 Corydon Ave., Winnipeg, MB, R3P 2G9. Ari can be reached at 204-291-5358.

trainedeye@iname.com