What Causes Windows to Warp?

Warping is a common problem with wood and vinyl window frames, and is the cause behind air leaks and difficult-to-operate sashes. But what causes windows to warp?

Causes Windows to Warp

What Causes Warped Windows?

Heat causes thermal expansion, which can cause materials like wood and vinyl to warp. While all materials expand and contract from temperature changes, not all materials revert to their original shapes when they contract. Vinyl, for example, can lose its shape permanently when exposed to heat for a long time – which is why vinyl siding that’s exposed to direct sunlight tends to sag over time. Window frames made of the same material are susceptible to the same kind of damage.

In addition to being susceptible to high temperatures, wood is also susceptible to the effects of moisture. During warm and humid seasons, untreated wood absorbs moisture and expands from the heat, which results in uneven expansion and contraction of cellulose fibers, resulting in permanently warped wood. This is why exterior wood components like decking, siding and window frames need to be painted or sealed.

Are Warped Windows Repairable?

Warping leads to sashes and frames not sitting flush when closed, resulting in difficult operation and gaps that allow air to leak through. Warped wood windows can be fixed by carefully planing the frame and/or sash, removing just enough to improve the fit, but not too much that it would introduce gaps. Unfortunately, the same can’t be done to warped vinyl windows. Also, some window hardware can be adjusted to ease opening and closing, but they do not fix gaps created by warping.

Fibrex® Material

Choosing windows made of warp-resistant material is the best solution against warped windows. Composites are best suited for this because of their even thermal expansion and contraction rates. Renewal by Andersen® replacement window frames are made of an exclusive type of composite called Fibrex. Made from wood fibers and polymer, this material exhibits the strength and durability of wood, the low maintenance of vinyl and the warp-resistance of composites – qualities that can give you years of reliable and worry-free service.

Learn more about the benefits of Fibrex from Renewal by Andersen of Houston. Give us a call at (281) 547-6177, or fill out our contact form to schedule an appointment. Our Texas service areas include Sugar Land and the surrounding communities in Fort Bend County.