An important issue in every inspection: roof leaks

Roofs are one of the most delicate elements in the entire envelope of a building. Any damage to the waterproofing can cause a leak very difficult to detect. Even in new buildings, leaks and leaks usually occur due to poor or poor waterproofing of the roof. In this short article we are going to discuss […]

Roofs are one of the most delicate elements in the entire envelope of a building. Any damage to the waterproofing can cause a leak very difficult to detect. Even in new buildings, leaks and leaks usually occur due to poor or poor waterproofing of the roof. In this short article we are going to discuss roof leaks and how to repair them. Here at Able Building Inspections you’ll find the most qualified professionals ready to assist you when you want to buy or sell a property with an inspection.

Diagnosis and roof repair tips

When we refer to roofs, we are talking about sloping roofs with tile roofs, slate or elements of small dimensions that overlap one on the other, being able to in old roofs, overlap without any type of grip element, that is, placing a tile on other.

Traditionally, ceramic tile or slate roofs had as their only waterproofing element of the entire roof the piece of tile or slate itself, which are in principle waterproof elements and therefore sufficient to prevent water from entering. The tiles or pieces of slate were placed overlapping in the form of a scale, one on top of the other in the direction of the slope, and some heavy element was placed on top to prevent them from moving due to the wind.

Currently, most of the roofs have more than one layer, each one destined to fulfill a specific objective. On the one hand we have the tiles or covering elements, on the other hand the thermal insulators and waterproofing and finally a support that can be heavy or light depending on the type of structure we use.

A leak has appeared, how to repair roof leaks

If you have come across the unpleasant surprise of having leaks on the roof, we will try to help you know what their cause is and how you can repair them, since it is perhaps not necessary to call any specialized company and you can do it yourself with Very little effort Of course, it is essential that you take sufficient safety measures to avoid any accident, make sure you have lifelines or tie yourself with a rope and harness to a safe point on the roof.

Leakage diagnosis

The first is to specify the origin of the leak. In traditional roofs leaks are usually due in 90% of cases to deficiencies in the covering, that is, poorly placed tiles, broken tiles or holes caused by breaks in the covering. In the remaining 10%, leaks may be due to defective or bad condition: chimneys or gutters.

To find out the origin of the leak the most advisable thing is to carry out water tests that consist of pouring water with a hose for a considerable time (one afternoon or a couple of hours) over a specific area, discarding the possible conflict points. It is advisable to start with complicated encounters: chimneys and gutters. Once these points have been discarded, an entire cover cloth should be tested.


Sometimes we can realise with only a visual analysis of what is the origin of the leak. For example, a gutter clogged by some element that causes the water to overflow and seep into the house. In fact, when the leaks are very large (with a large water filtration) the cause is usually in a clogged gutter that causes all the water in the roof skirt to end up leaking at one point, accumulating huge volumes of water that ends up entering the roof for a very specific area coinciding with the times when it rains the most.

Birds and their activities can be the source of leaks and roof leaks

Birds can be the cause of leaks. It is not strange to see a bird obstructing a downpipe on a roof.

If we have ruled out that the filtration is due to a break in any encounter, it is almost certain that the leak is caused by a defect in the covering (tile, slate or any other material).

Plants and their roots can cause roof leaks

Before proceeding to disassemble the entire roof and invest a large amount of money in something that may have a simpler solution, we will try to discard options, from lower to higher cost:

1-In the event that the leak comes from a meeting between different elements, we will proceed to repair it and subsequently apply a correct waterproofing (only in the affected area). For example, if we detect that the origin of the leak is a damage to the waterproofing fabric of the encounter between a chimney and the base of the roof.

2-In the event that the leak comes from the covering itself, the first thing we will do is visually inspect each tile or piece of slate. If we detect that any part is improperly placed or broken we will proceed to replace it or place it well and recheck the waterproofing of the cover, performing the water test again. It is usually quite frequent, especially in old tile roofs, that a tile has been moved by the effect of wind or a bird and a leak is occurring at that point.

3-If after an exhaustive analysis we have not detected damaged parts and the cover is in a quite deteriorated state, we will proceed to re-weave, waterproofing the support with an asphalt sheet or similar, if it is not possible, we can use a roof under tile similar to the typical wavy uralite. These are the cases in which the condition of the cover is quite defective and there are many broken parts. The most advisable thing is to call a specialised company to do the job and ask them to take advantage of as many tiles as possible from the old roof.

4-If the tiles cannot be recovered, we will be forced to place new parts, trying to anchor them correctly to the support. In these cases, it is better to carry out a comprehensive reform of the entire roof, fixing as many elements as possible and adding new layers to our roof whenever possible, for example a waterproofing sheet and an insulator.

It is not advisable to use waterproofing paints to waterproof the entire surface of the roof. Waterproofing paints are a good option when it comes to provisional repairs or when it is not possible to do anything else, but whenever possible, it is much better to fix the roof in an integral way, replacing insulation, waterproofing and covering (tiles).

Able Building Inspections are truly skilled specialists in the inspection of buildings that have been affected over time able to assist you when looking to make the smartest choice when looking to purchase a house.