The pros and cons of PVC roofing

Q: Is PVC roofing any good?

A: PVC on a low- or no-slope roof has a relatively long lifespan. This membrane product comes in different colors and thicknesses with different projected lifespans. Overall, I feel it is a great option but a bit on the spendy side (roughly double the expense of a torchdown roof).

All roof products deteriorate over time, and PVC has a tendency to shrink, pulling the seams, lifting corners and potentially causing leaks.

Older PVC roofs in cold weather are prone to shattering and puncture. As a result, the National Roofing Contractors Association recommends no foot traffic on PVC when the outside air temperature is below 50 degrees.

Older PVC can be difficult to repair, as the hot air welds used when it is new (no torch necessary!) do not “take” easily, and few sealants adhere to it for long.

The same limitations exist when a roofer makes a modification as a result of remodeling or storm damage.

Also, PVC and other PVC products such as pipe and vinyl siding are looked upon with some disdain from an environmental perspective due to chemical release of bio-accumulative toxins (notably dioxin) during manufacture and disposal.

Q: If I buy a condo conversion, am I falling under the protection of a new building warranty? My understanding is that condos are blessed with long warranties as a result of all the past lawsuits.

A: A developer may offer a warranty as an added benefit. But since it is an older building and it has only been modified (not built new from the ground up) by the developer, it does not fall under the state required staged warranty program, in-process inspections, third party insurance or other protections built into the 2003 condo law.

Conversions do have requirements for disclosure of an engineering review done prior to construction/renovation, but no real teeth to enforce those recommended upgrades. Conversions also undergo required municipal upgrades to bring the building to modern code regarding smoke detectors and other life-safety items.

Q: Can I paint vinyl siding? My vinyl wasn’t final as advertised, and the blue trim is a bit much now that it isn’t 1992 anymore.

A: That’s the first time I have heard someone get down on 1992. 1974, with its harvest gold, well sure, I understand that!

Vinyl can be painted, but you must not paint it a darker color than existing, as the darker colors will hold heat and may cause the vinyl to buckle and the paint to fail. Use high-quality latex, not oil-based paint. Make sure it is very clean before painting for best adhesion.

While I have no personal experience with paint containing urethane, I have heard from others that it works well on vinyl siding, as it flexes well with temperature changes. Some manufacturers offer paint specifically formulated for vinyl and aluminum siding. I think your idea of doing the trim rather than the body is less risky, as well.

Darrell Hay is a local home inspector and manages several rental properties. Send home-maintenance questions to dhay@seattletimes.com. Sorry, no personal replies.