Thatch Maintenance

A Thatched Roof after Maintenance, Eastern Cape

Thatched roofs need consistent maintenance to prolong the lifespan of the thatch and give you a problem free roof. There are a lot of factors that can affect the lifespan of a thatched roof including:

  • Natural degradation of the thatch over time
  • Inadequate thickness or compacting of the thatch when installed
  • Overhanging trees and shady settings
  • Humid climates
  • Improper maintenance
  • Incorrectly installed or blocked drainage valleys
  • Extreme weather (often wind or hail)
  • Bird and monkey damage

A thatch roof could be considered a “living” thing – it will naturally change over time and can be affected by external factors. When small problems occur it is best to address them as soon as possible to prevent them becoming more of a major issue.

Bosazza Roofing & Timber Homes have a specialist thatching team who are available to assess your thatched roof and create a maintenance plan as well as fix any current leaks or problems. We offer the following thatch roof maintenance services:

  1. Brushing, filling & compacting
  2. Patching problem areas
  3. Installation and clearing of drainage valleys
  4. Repairs to capping and ridges
  5. Remedial work on pole structures
  6. Re-thatching
We can also advise you on the longer term maintenance plan for your thatched roof so that you have an idea of when your roof will next need attention. 
"Jonathan did an excellent job in repairing leaks and re-thatching parts of my house. After trying several other companies over a few years time-frame, I can honestly say that he did the best job of them all."
Thatched Roof after Maintenance, Eastern Cape
Mr. N. Wagenaar
Maclear Manor B&B

Thatch Roof Maintenance Explained

A thatched lapa before and after maintenance

Brushing, Filling & Compacting

This is the most consistent maintenance that a thatched roof generally needs. You should consider getting your thatch roof or lapa brushed and compacted every 5 - 8 years. The process of the "brushing" or "combing" removes the ends of the reed which are slowly degrading over time. When a roof has been newly thatched it is usually a golden brown or yellow colour, as the thatch settles and begins to rot, the colour of the roof darkens. When the roof has been brushed it will return to a slightly lighter colour again. There is a right way and a wrong way to brush thatch so always consult a professional thatching contractor before you undertake any maintenance on your thatch roof.

Thatch roof with areas fixed by patching

Patching Problem Areas in the Roof

If there is a particular area in your thatched roof that is leaking or creating problems, this can be addressed with maintenance. That part of the roof might have been damaged by hail, monkeys or birds, or perhaps there are trees overhanging the roof where moisture builds up. A professional thatching contractor will be able to advise you about why the problem has arisen and will address it with suitable maintenance.

Installing & Clearing Drainage Valleys

Valleys are a common problem area in thatched roofs if they're not installed and maintained properly. There should be a valley in the roof in all places where water gathers to drain. The valley section should be made of a material that won't rust or rot in the elements and should be cleared of leaves and other debris so that the water can drain properly.

A thatched roof BEFORE and AFTER the drainage valleys were installed

Repairs to Capping & Ridges

Another problem area can be the cement capping or ridge at the top of the roof. Over time the cement capping is likely to crack which can let water in. The best way to deal with this is to seal the capping with a waterproofing membrane and sealant. Our thatching team install these precautions when they thatch a new roof to help prevent problems with the capping from the start.

Flashing around chimneys and where thatch meets other walls can be a problem area. Proper flashing needs to be fitted to avoid leaking.

Repairs and Remedial Work to Flashings

Flashing is installed where a roof meets a chimney or parapet wall. These areas often cause problems in thatched roofs if they are not installed properly. In some cases the existing flashing can be sealed with waterproofing to stop leaking, in other cases the existing flashing will need to be removed and a new system installed.

Remedial Work on Pole Structures

Unfortunately some structures are built without plans or an engineers design, and with inadequate pole structures or fixings. There is a wide range of problems that can be found with pole structures like this including: building with poles that are too thin, not using enough poles to support the weight of the structure, poles being untreated, poles not being joined properly with the right fixings. In some cases the pole structures can be fixed using extra bracing. In more extreme cases when there's a serious problem with the pole work, the entire structures needs to be re-built.

This lapa was collapsing and the pole structure failing


In some cases a whole section of the roof needs to be re-thatched (or even the entire roof). Our thatching team have worked together for almost 20 years and provide high quality thatching with premium Cape Reed. If the thatch needs to be stripped entirely we will also assess the condition of the support structure.

This roof was re-thatched; the original roof is stripped down to the pole structure and new thatch is installed on the roof.
This roof was re-thatched; the original roof is stripped down to the pole structure and new thatch is installed on the roof