Roof leaks are often unexpected and the potential damage is overlooked – in this article, we will discuss metal roof leak repair costs and available options. As a homeowner or a commercial property manager, you may be faced with a roof leak at some point. Metal roofing systems have becoming increasingly popular in North America and represent a significant portion of the roofing market. It is important to note that the details and causes involving a metal roof leak are unique, therefore, the roof leak repair options are unique as well.
Metal roofing systems are commonly installed on residential, commercial, agricultural and light industrial structures. More often, metal roofs are installed one residential homes with steep slopes (greater than 3/12 to be exact). There are some industrial buildings that use metal roofs as a waterproofing system and as the structural roof deck. Unfortunately, metal roofs are prone to leaking conditions in certain areas, but the chance is slim.
Some common issues that lead to metal roof leak repairs:
- Open seams
- Open penetration flashings
- Oxidation of metal roof
- Fastener failure
- Open ridge flashing
- Loose counter flashing
- Improper installation
- Damage on metal panels
Before we discuss the metal roof leak repair options, it is important to understand the difference between structural and architectural metal roofing systems. An architectural metal roof system is installed over a separate structural roof deck. These roofing systems can be found on most residential applications. In a structural metal roof system, installers will install spruce wood strapping (horizontal and vertical) directly onto existing shingles and attach metal tiles to the strapping. This facilitates adequate ventilation in the attic space and reduces the chance for mold and fungus growth. It is important to note that in this metal roofing system, there is a separate structural deck that supports the metal panels.
Another design characteristic of metal roofing systems to consider is the slope. Metal roofing tiles can only be installed on a slope greater than 3/12, however, some standing seam roofing systems can be installed on any slope. Hydrostatic metal roofing systems are deigned to retain water until it can drain. Meaning, these roofs can hold water without leaking. There roofs are commonly found on larger pre-engineered structures since it would be more costly to build with a steep sloped roof assembly. There roof leak repairs are less common since the system is deigned with additional waterproofing elements in mind. In a hydrokinetic metal roofing system, these systems are designed to shed water immediately. They are commonly found on residential and commercial structures where water cannot remain on the roof since the slope is steep. In the case that water is retained on the roof, it can create hydrostatic pressure forcing water into the creases creating leakage problems. The metal roof leak repair cost will be determined by the extent of the damage, the location of the job, and the difficulty.
Common reasons for metal roof leak repairs include improper installation and mistakes in the design of the metal roofing system. The majority of the leak issues relate back to the flashings and details used to finish off the metal roofing system. They may not show up immediately after installation and may take time to develop.
Some of the most frequent metal roof leak repairs include the following:
Opening in horizontal seams that are prone to separation over time. It is important to ensure that the roof contractor considers the expansion and contractions of panels in extreme weather. Metal roofs in Toronto are prone to expansion and contraction because of temperature changes they experience all year. This movement causes stress on the fasteners and may cause penetrating leaks. Metal roof oxidation may also become an issues since they are often made from a variety of materials including copper, steel, aluminum and tin. Although most metal roof panels are made of sheet metal and have been coated, this coating may wear off overtime causing the metal panels to oxidize. Such roof leak repair cost will vary since oxidation often impedes repairs and makes it difficult to apply sealant.