Wildfire is a fascinating and terrifying thing.
There's some attention to wildfire danger in the
permaculture designer's manual; the Australians have a lot of relevant
experience and intense bush fuels to manage.
I've been discussing this on another site, and thought we might want to kick more ideas around here.
Here's the last post from that site to date:
Here's a good summary of recommendations in the western USA. You may find similar recommendations from
local sources [for Portugul, Australia, Spain, or other similar arid and resinous-species-rich climates].
http://www.firewise.org/wildfire-preparedness/be-firewise/home-and-landscape/defensible-space.aspx?sso=0
How to integrate this advice with good
permaculture design is the question.
(Our current house is not it.)
There's a potential conflict between flammable shrubs and debris in Zone 1 for fire protection, and biological resources for intensive
gardening (mulch, perennials, etc) in Zone 1 for
permaculture.
I might look at something like earth-shaping
berms and swales, or short masonry walls in rings around the house to help define the garden. Something like that could catch flammable debris / mulch in pits, where you can use it for
gardening, yet shield the house from the radiant heat it might release if it burns. And it might cut down wind speeds at ground level (or however high you build the walls). You could also conveniently remove any windblown debris or gutter-cleaning debris into nearby mulch pits for the
permaculture garden.
For house finishes and integrated systems right up against the house, like
chickens,
water catchment, etc, consider using non-flammable materials like earthen building, lime plasters, and metal or ceramic roofs and water containers, rather than plastics. We've seen excellent fire protection effects from coating or embedding normally-flammable materials in clay, for example light clay-staw insulation tested in Ontario for timber-frame infill.
Fascinating and timely topic! The Australians also have a lot of good, relevant experience.
Other threads already engaged here:
https://permies.com/t/24772/permaculture-design/Fire-breaks-protection-permaculture-setting
(the discussion didn't go very far, but it's another place to look at strategies.)
Zone and sector analysis:
Fire is most likely to approach in our area from downslope, upwind (west in summer, NW in winter), from lightning strikes (anywhere), and from human-caused fire sources (hot engines driven over dry grass, people using chainsaws or lighting fireworks during a burn ban, absentee cooking, absentee heating, and other ill-managed DIY infrastructure like electrical fires).
So we have specific directions we watch during fire season, including specific neighbors.
https://permies.com/t/31091/pdm/Zone-sector-analysis-Design-application
Chapter 12 of the designer manual has a wildfire section, we could expand on this if anyone wants to go in-depth:
https://permies.com/t/34465/pdm/Permaculture-Designers-Manual-Chapter-HUMID#269777
Ironically it's in the HUMID climates chapter, whereas I would think there's more concern in ARID climates (ch. 11).
But the humid / seasonally dry areas (mediterranean, monsoon) have lots of fuels, waxy and resinous species, and annual periods of high fire danger. So there it is.
Yours,
Erica W