FAQs

Should I fit a spark arrestor?

No. The fitting of spark arrestors is not recommended because the mesh has a tendency to become blocked by soot and tar, and can be difficult to clean. 

In this condition, they are likely to increase the risk of chimney fires. But we always advise to confirm these details with your insurer before proceeding with any actions.

What is the recommended chimney height above the thatch?

Current building regulations say the minimum height is 1.8m.

Is my chimney lined?

If you don’t know, then we recommend that you contact your local HETAS-approved engineer to complete a chimney survey and make the required recommendations. Find out more…

How long does a thatched roof last?

The life of thatch will depend on a number of factors which include the pitch and design of the roof, type and quality of thatch material used, geographical location, and degree of skill exercised by the thatcher. In ideal circumstances, thatched roofs have been recorded to last in excess of 100 years but under normal conditions, the following approximate life expectancies can be used as a guide:

• Water Reed - 30-50 years
• Combed Wheat Reed - 20-30 years
• Long Straw - 15-25 years

How long does a ridge last?

Depending upon the style of construction and type of material that is used, ridges can normally be expected to last between 10-15 years.

How do I identify what material is on my roof?

Not easy to define, but the following generalisations may give a clue:

Water Reed

• Even dense coat showing butt ends of material only
• Likely to be angular in overall appearance with eaves dressed into place, ends of material at right angles to the stem
• Likely to have a ‘block’ ridge
• Likely to have wire netting on the ridge only

Wheat Reed

• Even dense coat showing butt ends of material only
• Likely to be softer and more rounded in appearance with eaves cut into shape leaving an angled quill-like end to the straws
• Likely to be totally covered with wire netting

Long Straw

• Less dense and more ‘shaggy’ appearance to coat, may show a mix of butts and ears
• Soft contours to the roof, especially windows
• Should have a continuous line of hazel rod running on the surface at eaves and gables
• These are called ‘liggers’ they may appear as two lines with cross-sparring between them

NB: Be cautious, thatching materials are not easy to identify and there are many subtleties and distinctions to be wary of.

Does my roof have a fire barrier?

If you can access your roof void safely, look between the rafters at the underside of the thatch. If you can see the thatch, you do not have a fire barrier. If you can see a sheet or board material you may have a fire barrier. Try to establish whether this material is a bituminous or other type of sarking felt which does not constitute a fire barrier, or it may be a fibre cement boarding or shiny flexible material which could be a fire barrier.

What fire retardants are available?

Please review the Fire Barriers & Systems section of the website.

What does it cost to re-thatch a roof?

Approximately £100.00 – £125.00 + VAT per m² of roof area including overhanging of eaves and gables (excluding scaffolding).

How thick is thatch?

A single coat or thickness of thatch is normally between 300mm and 350mm. This thickness will reduce throughout the life of the roof as a result of natural erosion.