Thatching Questions & Answers:


How long does a thatched roof last in typical Southern African conditions?:

It can last about 40-60 years, depending on site, condition and angle.
The life of a thatch roof is dependant on a number of factors. The quality of the grass used, the angle at which the roof is constructed and climatic conditions. Thatch will last far longer in a climate that is either hot and dry or cool and damp. Should the climate be hot (30° plus) and high humidity, the conditions for fungal growth is good and leads to deterioration of the roof in a far shorter time. An average life span for the thatch layer under normal climatic conditions in SA is approximately 20 years.

What maintenance will I have on my roof?:
  1. Thatch maintenance:
    Re-compacting after three years - this means pushing the grass back in the opposite direction it has moved over time. By re-compacting the grass, the brittle end points are broken off allowing for better water run-off, but at the same time thinning the thatch.
  2. Timber maintenance:
    No maintenance is required for the timber. All our timber is SABS C.C.A. treated and is therefore insect repellant and guaranteed against rotting.

How long does it take to thatch a roof?:

A team of three men under normal working conditions will thatch between seven and ten square meters of surface area per day. A normal domestic house roof of 350 m² roof area would take 6 teams about seven days to thatch.

Does thatch keep out water?:

Yes. Thatched roofs do keep out water. This is possible because of the minimum pitch of 45°, and because the thatching reed is packed to a density of approximately 35 kg/m² throughout the roof. These elements work together to provide a roof that is not only beautiful, but watertight.

Isn't thatch a fire risk?:

Our fire retardant thatching methods enables our clients to enjoy special insurance rates, making insurance affordable and on par with normal roofing insurance.

We employ two methods to achieve fire retardation, namely:
  1. the fire "blanket" - woven into the thatch.
  2. Fire sprinkler systems.

Does thatch hold up in coastal storms?:

If the roof and especially ridges and gables are constructed and thatched correctly thatch roofs can withstand severe wind and storm conditions.

What about pests?:

Thatch roofs occasionally do harbour insects. Very often as a result of insects laying eggs on the grass prior to thatching and occasionally while the building is inhabited. Use of a good insecticide is recommended on these occasions. The exterior of the roof is subject to damage by baboons and monkeys. This damage is alleviated by covering the entire thatch surface with galvanised wire netting.

Do all thatch roofs go black?:

Yes, all thatch roofs do go black. The discolouration is due to rot. Good thatch surface texture blackens more rapidly than poor surface texture due to less exposure of the grass stem. The climate also determines the rate of rot.

Why Cape Thatch Reed?:

Cape Thatch Reed last so much longer than grass (4x longer) and is more expensive.