If you’re like most homeowners, you probably don’t know what a lintel is, let alone that they need to be maintained. A lintel is a beam supporting masonry above an opening in a wall, such as a window or door opening. Lintels may be made of wood, masonry or steel. The focus of this article, the second installment of the Helpful Home Inspectors’ Best Kept Secrets of Home Maintenance, is steel lintels. Lots of homes in our area have brick or stone walls with steel lintels.
According to the Brick Institute of America (BIA), these steel lintels will require periodic maintenance to avoid corrosion.1
Corrosion, also known as rust when the term is applied to steel lintels, causes the lintel to expand. The expanding lintel exerts pressure on the surrounding brick or stone work, resulting in cracks and movement. I see this a lot, even in homes that are otherwise very well maintained. That’s why I’ve included maintaining steel lintels near the top of the list of Best Kept Secrets of Home Maintenance.
It has become a fairly common practice around here to cap the lintels with aluminum and seal them with caulk. Looks good, but this practice may do more harm than good. By trapping moisture within the wall assembly, we promote rather than inhibit rust. Again we turn to the BIA for guidance. They advise that proper consideration must always be given to moisture control wherever there are openings in masonry walls. There must always be a mechanism to channel the flow of water, present in the wall, to the outside.1 A lack of flashing and weep holes in the original construction may limit the flow of water to the outside (a good topic for a future blog post). Capping and caulking may make matters worse.
The BIA does not provide specifics on how to maintain steel lintels. So, what’s a responsible homeowner to do?
When I find evidence of rusty metal lintels, I generally recommend that they be cleaned, primed and painted to reduce the risk of further deterioration that could require costly repair. Use high quality paint specifically formulated for use on exterior metal surfaces. Expose any metal lintels that are capped in aluminum or are similarly concealed. Repair any damage to the surrounding masonry.
By the way, painting the lintels with the same paint used for the exterior wood trim won’t get the job done. I often see the rust bleeding right through the paint.
If the lintels are allowed to continue to rust and deteriorate, they will eventually need to be replaced – a process much more costly than paint. If the lintel is sagging noticeably or if damage to the lintel or the surrounding masonry is severe or if problems recur despite maintenance efforts, the lintel may need to be replaced. In that case, the use of galvanized steel lintels and/or improved flashing techniques may serve to extend the life of the new lintel. Discuss these options with your masonry contractor.
During a professional home inspection, a Pennsylvania home inspector will inspect the readily accessible, visually observable components of the wall structure and cladding. If he or she finds evidence of rusty metal lintels, it will be noted in the home inspection report.
I hope this is helpful.