Gutters, fascia and downpipes in Nairobi

Guttering is the cheapest part of a roof and it causes a disproportionate share of the expensive problems. A blocked or badly fallen gutter holds water against the bottom edge of the sheeting and the fascia behind it. Timber fascia in that condition does not last, and by the time it is visibly rotten the rafter ends behind it are often wet too. What began as a gutter that needed clearing becomes carpentry.

What we fit

• UPVC guttering and downpipes, which is the common domestic choice and what most Nairobi houses now carry. From about KES 388 per linear metre supplied and fitted.
• Metal guttering, where a run is long, exposed, or has to match existing work. We have not found a reliable published Kenyan rate for metal by the metre, so this is quoted.
• Timber fascia and barge boards, replaced in seasoned timber and finished rather than left bare. This is carpentry, which is the half of this business the name is about.
• Valley gutters between roof planes, which are the ones that cause internal leaks rather than merely wet walls.
• Leaf guards where a compound has mature trees close to the roofline.

Falls, brackets and outlets, which is where it goes wrong

Most failed guttering in Nairobi was not badly made, it was badly hung. Three things decide whether a gutter works:

The fall. A gutter needs a consistent slope towards the outlet. Hung level, or hung with a dip in the middle, it holds standing water, sags further under the weight, and eventually pulls its brackets out of the fascia.

Bracket spacing. Brackets too far apart let a full gutter flex between them. That flexing is what breaks joints, and a broken joint discharges straight down the wall.

Outlet and downpipe capacity. One undersized downpipe on a long run will back up in a heavy storm no matter how good the gutter is. Nairobi rainfall arrives in short intense bursts rather than steady drizzle, so peak capacity matters more than average.

Fascia first, or gutter first

If the fascia is soft, fitting new guttering to it is wasted money because the brackets have nothing sound to hold. We check the fascia before quoting the gutter, and where the timber has gone we say so. It is a more expensive answer and it is the honest one.

Where fascia has gone because the guttering failed years ago, the roof edge usually wants looking at as a whole: see re-roofing and replacement and, for sheet rates by gauge, mabati and roofing sheet prices.

Timing

Guttering is the one roof job that is genuinely worth doing on a schedule rather than in an emergency. Search interest in gutters in Kenya peaks in March, at the height of the long rains, which is precisely when it is least convenient to have a roofer on the house and when everyone else wants one. Clearing and re-hanging in the dry months costs the same and prevents the damage rather than documenting it.