A leaking roof might feel like an overwhelming issue to deal with and does not always mean that you will be burdened with the massive expense of replacing your roof (unless you have roof insurance to assist with the cost). More often than not, a simple repair to the roof or an item on the roof, such as gutters, may solve the leaky roof, with moisture drying out before any further damage is caused to the inside of your property.
Of course, the longer it takes to discover the leak, means the more chance of extensive damage. If you have access to your loft make it a regular habit of going into the loft space monthly to check that there are no signs of moisture or mould. When in the loft space, turn off any light you may have, so that you are standing in the dark. If you can see windows of light streaming in through the roof, this might expose a missing roof tile or a hole in the roof.
If you have access to the loft, an idea would be to stand in the loft and circle around where the water leak is coming from. Take note of whether it is a leak that is dripping when raining or a sign of moisture on the roof joists with the joists feeling wet. Are there mouldy patches on the joists but they feel dry to the touch?
If a dripping leak, get someone to stand outside with a hosepipe and gently spray your roof. Stay in communication with them, perhaps talking on mobile phones, so that once you notice the leak dripping they can explain which part of the roof they are spraying. In case the water had travelled to the leak, wait an hour and then redo the test with the person spraying directly on the area where the drip started to see if it sets off almost immediately or if there is a few minutes delay.
Another way to check where a roof leak is coming from, ask a neighbour who might look out onto your roof, if you can have access to their window, so that you can inspect your roof for any visible signs of damage or missing shingles or tiles.
When discussing the leaky roofer with a professional roofer, and explaining that you cannot find the source of the leak. They may have access to electronic testing equipment.
To identify a leak on a flat roof, the electronic testing tests the waterproofing integrity of roof membranes. Infrared cameras can show cold spots signalling a possible leak in the roof, by highlighting areas of moisture.
Moisture path analysis will measure different moisture levels. High levels of moisture are a strong indication of a leaking roof.
Depending on the location of your leak, and if the rest of the roof is in general good condition, not too aged, then instead of the expense of an entire new roof, a small repair to the leaky roof will be all that is required to stop the water damage.
Most repairs would take a skilled roofer a day to complete. This could involve replacing damaged or missing shingles. The roofer may only need to change one shingle or a handful around the area of the leak, using fresh cement to seal the shingle.
Fixing the leaky roof could be as simple as re-caulking around a chimney, roof vent or skylights flashing. This will fill up any pinhole gaps that might be allowing water through. If it is the flashing around these areas that has failed, the roofer may need a day to renew the flashing.
Another simple fix might be cleaning clogged debris out of the gutters to ensure the rainwater is flowing down. Any mortar around the roof, including the chimney might need repointing to stop water from getting in.
The most expensive part of a roof repair could be the need for scaffolding to give the roofer access to the leak on the roof, rather than the labour costs. Of course influences to the price will be the sort of roof you have, how high the pitch of the roof is as well as the scale of the problem. Most small roof repairs can be completed with a day or two labour charges, from renewing a section of flashing or replacing one or two shingles.
A more complicated roof repair that might involve strengthening wooden beams and the structure of the roof will need more days of labour. Roof repairs should be undertaken during dry weather but living in the UK this is not always possible. The roofer may create a tarpaulin covering over the section of the roof being fixed to keep the rainwater out during the repair work as well as keeping them safe on the roof in slippery conditions.
Cost to repair a leaky roof |
Per |
Average total labour cost |
Roof inspection to determine source of leak |
Per hour |
£120 |
Repairing some failed mortar on the roof to stop water leak |
Per hour |
£90 |
Recaulking around flashing to stop a leak on roof |
Per hour |
£80 |
Fixing a damaged shingle to prevent a leak |
Per hour |
£80 |
Repairing a patch of leaky roof membrane |
Per hour |
£95 |
Always try to repair the weak area on the roof first before replacing the roof. This is not only to avoid the cost of a roof replacement but because of the time and disruption involved in having a new roof fitted onto your home. A roof repair might just involve one day of disruption without you needing to move out of your home.
Even if the roof damage is severe, a hole left in the roof from a fallen tree branch or a strong hail storm. As long as the roof structure is still mostly intact, even if one roof rafter is damaged, a professional roofer should be able to repair the area of roof. Matching the roof tiles or shingles to the rest of the roof, and replacing the damaged section of waterproof membrane and strengthening the rafter or beam if weakened by water or the impact of the fallen debris.
The causes of a leaky roof can be anything from an ageing old roof desperate for replacing to missing shingle or roof tiles or damaged flashing.
The most common causes of roof leaks according to UK roofers are;