Roof leak repair in Nairobi

A leak shows itself in the wrong place. Water enters at a failed joint, a lifted sheet or a blocked gutter, then runs along a purlin or the underside of the sheeting until it finds somewhere to drop. By the time it marks a ceiling it may be several metres from the hole. That is why patching directly above the stain so often fails, and why the same room is leaking again a fortnight later.

So the job starts with finding it, not sealing it.

What we actually look for

Most Nairobi leaks come from a short list, and the list is about details rather than the roof covering itself.

• Ridge and hip joints, where sheets meet and the fixing has worked loose.
• Flashings and abutments where the roof meets a wall, a parapet or a chimney. On maisonettes this is the most common single point of failure.
• Nail and screw penetrations, particularly where a sheet has been fixed through the valley of the profile instead of the crown, or where the rubber washer has perished.
• Blocked or undersized gutters, which back water up under the bottom edge of the sheeting. This one is worth naming twice, because it is very common and it is cheap to put right compared with what it eventually does to fascia boards.
• Valley gutters between two roof planes, which collect debris and then overflow inwards.
• Lifted or walked-on sheets, often from someone servicing a solar heater or an aerial.
• Rotten or sagging timber, where the structure has moved and opened a joint that was sound when it was built.

On a flat or partly concealed roof the causes are different again and usually come back to a failed waterproofing membrane or a ponding area with nowhere to drain.

Why we do not quote a leak over the phone

We publish market rates on this site wherever an honest one exists. For leak repair there is no useful published figure in Kenya, and we are not going to invent one. A leak can be a single perished washer or it can be forty metres of failed ridge with three rotten purlins underneath, and the difference is not visible from a photograph of the ceiling.

What we do instead is inspect first, tell you what is causing it, and quote for that. If it turns out the roof is past repairing we will say so rather than sell you a patch that buys four months.

Before the rains rather than during them

Leak demand in Kenya is strongly seasonal. Search interest in roof leaks runs roughly fourteen times higher in March, at the height of the long rains, than in September. Interest climbs steadily from November through to March, which means the short rains in October to December are the warning and the long rains are the bill.

The practical consequence is that the cheapest time to deal with a suspect roof is before it is actively leaking, and the worst time to find a roofer is the week everyone else is looking for one. If a ceiling marked last season and nothing was done, it will mark again.

If the answer turns out to be replacement rather than repair, the sheet and labour rates are on mabati and roofing sheet prices, and what a full job involves is on re-roofing and replacement.

What we do about the ceiling

Fixing the roof stops the water. It does not undo the damage underneath, and a stained or sagging gypsum ceiling usually needs cutting out and replacing rather than painting over. We do that work too, which means the repair and the making-good are one job and one responsibility rather than two trades blaming each other.

Send a photograph

A photograph of the stain, and one of the roof from outside if you can get it safely, is usually enough for us to tell you what is likely wrong and roughly what it involves before anyone visits. Do not climb on the roof to take it.