Protect Your Home

Last updated on April 20, 2018

STEP 1 : Assess Your Risk From Wildfire

The risk we took not preparing our homes for wildfires in Portugal is plain to see after the fires of 2017. The land is more or less bare so now is time to start from scratch to prevent, or at least mitigate, the destruction when it happens again.

For those rebuilding their burnt-out or fire-damaged properties or renovating a newly bought property in Portugal, there is a lot you can do to prepare your home for future wildfires.

Understanding the fire risk of your area

If you are house-hunting in Portugal you should consider the location of a property with respect to future forest fires. Consider the following risk factors and if they apply to you, the more fire protection measures you’re likely to need.

How long is the Fire Season?
High risk areas have a long fire season with heavy available fuel loads. Low risk areas have a shorter fire season with little available fuel.

How steep are the nearby slopes?
If you live on or near very steep slopes, it’s a high risk area. The steeper the slope, the faster a fire will burn up it. A low risk area will have gentle slopes or be quite flat.

How much vegetation is nearby?
Fires need fuel to burn. If you have a heavy coverage of long grass, forest and woodland-floor litter and flammable scrub nearby, you’re in a high risk area. A low risk area would have little or no such fuel.

How dry is the nearby vegetation ?
The drier the vegetation, the greater the fire hazard. The vegetation will naturally dry out through the summer, but it will also gain and lose moisture during the day. This is as a consequence of humidity and temperature changes – early mornings have the highest moisture content and mid-afternoon the lowest.

How often do wildfires occur?
Some places have a history of wildfires. The more often fires have occurred in the past, the higher the potential risk.

How good are the roads near you?
Low risk districts have many good roads providing easy movement through the area. High risk areas have a single, long dead end road, or roads that are easily blocked by falling trees.

Topography and wildfires

Research into why homes burn in wildfires has shown topography is a very important factor because of its effects on fuel and local weather.

The topography of a region is characterised by the altitude, slope and exposure. It has a high impact on all the following weather features which may contribute to fire propagation or hinder it…

• Local rainfall.
• Air temperature.
• Type and amount of vegetation.
• Influence of sun on slope aspects and elevation effects fuel moisture.
• Local wind patterns.
• Orographic (pertaining to mountains, hills or elevated terrain) lifting of air masses can lead to lightning, convective storms.
• Slopes affect fuel pre-heating which affect fire rate and direction of spread.
• Certain land forms attract lightning ignition.

The CTI report 12 October 2017 (Relatório da Comissão Técnica Independente) observed the contribution of topography to the Pedrógão Grande fire…

The direct effect of slope on fire propagation velocity is relevant in a fraction of the territory that burned, since the predominate terrain has little or moderate sloping. There are, however, other dimensions of the orographic effect on fire behaviour, related to wind channelling, which would amplify the effect of wind gusts accelerating the fire, or with the increase of turbulence in more wavy and complex terrain (J Coen 2017). Depressions on the ground are particularly affected by downbursts. These interactions may partly explain the many situations and village interfaces where vegetation, having only burned projections, was desiccated by hot air.

…the slope of the terrain from Vila Facaia to EN 236-1, about 10% on average, represents an increase of 67% in the rate of fire propagation compared to flat terrain.

High risk house locations include all or any of the following:

• On a slope or at the crest of a slope or hill is the most dangerous location. Read More
• Isolated in the middle of a flammable eucalyptus and/or pine forest, among overgrown fields or scrub-land, with one access road.
• Isolated on the edge of a village surrounded by flammable woodland or overgrown fields or scrub-land.
• Within a linear village or town with one side of the house facing a road and the rear and/or sides exposed to flammable woodland or overgrown fields.
• Any location where the only road access is a long way through flammable woodland.
• Houses near high or medium voltage power lines where fuel management measures (the responsibility of the electricity company) have been neglected.
• Houses near railway lines where fuel management (the responsibility of the rail company) measures have been neglected.

Low risk locations may include:

• Houses located within a central ‘concrete cluster’ within in a village or town but owners must still ensure the property is clear of any debris likely to ignite from flying embers.
• Middle of a large town or city.

Access & Escape Routes

It is vitally important that the road to your house is accessible for firefighters. Try as they might, firefighting trucks will find it impossible to get to you if you live miles out in a burning forest along a narrow dirt road.

If you have a driveway leading to your house, keep the land on either side of it clean of flammable vegetation and prune trees that may overhang the driveway, so emergency vehicles can pass easily.

If you have gates make sure they are wide enough to get fire-fighting equipment through.

House Design & Building Materials

If you live in a house or cabin which is fully or partially made of wood or straw bales, in a caravan or other temporary structure in a high risk location, your property will almost certainly be damaged or destroyed by wildfire.

If you are building from scratch, renovating or simply looking for a property to buy in rural Portugal, some things to consider to protect yourself against wildfires would be…

• Roof constructed with cement, slate, iron shingles or sheets, clay or concrete tiles, exposed concrete slab or roofing composite material approved as non-combustible.
• A steeply sloping roof is more fire resistant than a flat roof as burning embers should roll off.
• If you have solar panels on your roof, make sure they are fitted so that there is sufficient gap between them and the roof surface, so burning embers cannot be caught beneath the panel.
• Any skylights should be made of non-combustible thick safety glass, not acrylic which will melt in a fire.
• Walls constructed of non-combustible materials such as brick, stone or stucco – definitely not untreated wood.
• Windows multi-layered glazing with tempered glass with aluminium or PVC frames – not untreated wood. Small windows survive better than large ones. Aluminium (or similar) window shutters or blinds add another layer of protection.
• Balconies pose particular problems because they overhang and usually face views over the very land from where a wildfire may come. They should be constructed from non-combustible material and if they are on stilts, the underneath area should be preferably blocked in. Keep them as free as possible of combustible furniture and rugs at high fire risk times.
• Any outbuildings such as woodsheds, workshops or garages should preferably be detached from the house and a minimum 10 m from the house.
• Any decking should be made of treated wood but a look-alike non-combustible composite material would be better.
• Install multiple external water taps and hose(s) which are long enough to reach all areas of your house, outbuildings and any other structure. Do not rely on water pumps dependent of mains power which is likely to fail in a wildfire.

Can wood ever be fireproof?

The answer is not really. Even manufacturers of treated fire-resistant hardwood timber, say “in hardcore wildfires, no matter how fire resistant wood is, when a firestorm is bearing down on your place, all bets are off” – and you really can’t get much more ‘hardcore’ than the Pedrógão Grande fire.

So if possible, steer away from using timber as your main building material and for elevated decking, external stairs, balconies, stilts and raised verandahs. If you do build with wood, use the densest hardwood timber available, particularly for exposed rafters and on the exterior. Rough-sawn timber is more flammable because it easily catches dust and debris, so give it a smooth finish. Wood coatings and resinous sealants are also very flammable.

A word about gutters…

Every piece of wildfire prevention advice mentions keeping your gutters clear of combustible debris especially in the Critical Fire Period or at any other times when the fire risk is rated High to Maximum. Quite frankly, if you live next to a eucalyptus or pine forest, you would have be up a ladder practically every week with the amount of debris that flies out of a forest. Like many houses in Portugal, it may be better not to have any gutters and just put up with the rain running off your roof. If you really must have gutters, install high quality metal mesh gutter guards (not plastic or the brush type which will melt of burn in a fire).

Source: An Overview of Resilient Construction

STEP 2 : Protect Your House Itself

A defensible space is essential to improve your home’s chance of surviving a wildfire. It is a buffer zone between a building and the vegetation such as grass, trees, shrubs, or forest areas that may surround it. This space is needed to slow or stop the spread of wildfire and it protects your home from catching fire—either from direct flame contact or radiant heat. The defensible space is also important to provide protection and room for manoeuvre of the firefighters defending your home.
Embers and small flames are the main way most homes ignite in wildfires. Embers being burning pieces of airborne wood and/or vegetation that can be carried long distances on the wind. These cause ‘spot fires’ by igniting vulnerable combustible parts of a house, flammable debris and other objects. To minimise the risk to your home…

Within 0 to 2 Metres Of Your House

• Clean your roof and gutters of dead leaves, debris and pine needles that could catch and be ignited by embers.
• Replace or repair any loose or missing shingles or roof tiles to prevent ember penetration.
• Some older houses in Portugal have small vents in the roof space or attic, in ground floor adegas/workshops or in the eaves which embers could pass through. Install small 1/8″ metal mesh screening or a metal plate.
• Repair or replace damaged or loose window shutters/blinds and any broken windows. Windows are particularly vulnerable in wildfires from radiant heat or direct flame contact which may cause the frames to ignite and the glass to break – the fire is then able to move from the outside to the inside of the house.
• If you have a raised decking or patio area immediately outside your house, clean all debris out from underneath and screen or box-in the areas below with wire mesh to prevent debris and combustible materials from accumulating. Remove anything stored underneath decks.
• Move any flammable material away from all your exterior walls such as compost, flammable plants, piles of dead leaves and needles, piles of firewood, straw bales, animal feed etc  – basically anything that can burn.
• Remove or prune flammable plants and shrubs near windows.
• Create a clean hard surface pavement 1 to 2 m wide around the whole of your house. This could be made of cement, crushed stone, large stone gravel or flag stones. As of 14 February 2018, Portuguese law states this must be done whenever possible.

Gas Cylinders

Gas cylinders need a special mention… Many of us in rural Portugal use propane or butane gas for hot water, indoor cooking or barbecues and we often store the cylinders outside near our houses within the 2 metre zone. These cylinders can become a particular hazard in a wildfire.

Any gas cylinder that is exposed to fire or excessive heat can rupture due to increased pressure caused by the increase of temperature. Even those fitted with a pressure relief device may rupture because the device may not operate quickly enough. The rise in pressure may cause parts of a cylinder to break and become dangerous projectiles and the flammable gas to ignite.

So special gas cylinder precautions for high risk forest fire areas include:

• Clearing all flammable vegetation, leaves, debris and any other combustible items for at least 3 metres around your cylinders and gas barbecue.
• Make sure your gas cylinders and gas barbecue are at least 3 metres from your house or any other outbuilding.
• House your gas cylinders in a purpose-built fire-resistant metal cabinet, such as these.
• The speed and ferocity of the 2017 firestorm left few of us time to do anything except run for our lives. However if a more ‘normal’ wildfire threatens and if you do have time, shut off the gas cylinder – but only if it is safe to do so.
• If you do evacuate, use extreme caution when returning to your house. If you have any worries about the condition of your gas cylinders, the gas pipes, vents or the water heater, don’t try to fix things yourself – call a maintenance technician from a gas supply company.

Firewood Storage

This is another issue that needs a special mention because many of us in rural Portugal use firewood to heat our homes. The fuel management law stipulates there should be no combustible firewood in the 50 metre fuel band. So where do you put your firewood to keep it dry and convenient to use as well as being safe in a wildfire? And what if your own land is less than 50 metres radius?

You’ll basically have to use your best judgement for your individual circumstances…

• Store your firewood as far from your house or other buildings as possible – preferably 6 to 10 metres. When doing this also take into account the distance from your neighbour’s house and property boundary so you don’t inadvertently put them at risk.
• Preferably store firewood in an enclosed shed – and preferably a fireproof shed, not a wooden shed.
• If you store your firewood or wood pellets in a ground floor adega or workshop within or attached to your house, make sure you screen any air vents where burning embers could gain access.
• Apply fuel management measures to your woodshed or loose pile of firewood – remove all combustible vegetation and debris from around the firewood and preferably create a 1 to 2 metre hard surface firebreak around it.
• Do not leave wood stacked up against the outer wall of your house or any other building, or in a garage with a motor vehicle.
• If you don’t use a woodshed and keep it in a loose pile outside, make sure it is on flat ground. A flat surface will prevent burning logs rolling away if it catches fire.
• Cover a loose stack of wood with a fireproof tarpaulin particularly during the fire season.
• If you use highly combustible wood-based mulch, animal feed and bedding, store it in the same way as firewood – not near your house.

From 14 February 2018 the Portuguese law stipulated fuel management measures must be carried out within a total of 50 metres from your house. This is supposed to be achieved by 15 March 2018. Note, this law applies only in rural areas where there is close interface between forest and dwellings / buildings. It does not apply to ‘wild’ forested land away from populated areas.  Read more on the latest fuel break laws in Portugal

In Portugal, any defensive spaces created to protect against wildfires are known as Fuel Management Bands / Faixas de Gestão de Combustivel

This is where defensive landscaping around your house can influence the behaviour of a wildfire, decreasing it’s destructive potential by keeping flames smaller and on the ground. As a wildfire moving swiftly through tree crowns and/or along the ground, closes in on your home, it should gradually diminish due to lack of flammable fuel. It may continue to burn at this distance but your house should stay intact with minimal damage.

In Portugal creating the legal fuel management band does NOT mean removing all vegetation in the 50 metre space, as in the case of a bare earth ‘firebreak’. The aim is cleaning the land NOT clearing it completely. It also does NOT apply to agricultural crops such as olive trees or vines.

Do not be tempted to eliminate all vegetation or trees in this space because this growth will catch embers rather than letting them possibly roll on to the house. Also when a fire front hits a completely bare area, often a shower of embers are released which can make matters worse. The basic rule of thumb is to reduce vegetation so that 50% of the ground remains covered by a canopy.

Some municipalities across Portugal have send out their own brochures or notices to their residents advising them about the fuel management law. Judging by social media comments these have caused much confusion and even more confusion when translated into other languages.

So starting from the external walls of your house…

• As mentioned above, create a clean hard surface pavement 1 to 2 m wide around the whole of your house which is technically a firebreak. This could be made of cement, crushed stone, large stone gravel or flag stones – it is up to you. The law states ‘whenever possible’ so if you can’t do for any reason, you have not broken the law. However this measure is very highly recommended.
• There must be no accumulation of any combustible substances or other highly flammable substances such as firewood, other wood or cutting debris (from forest or agricultural use) immediately close to your house or within 50 metres of your house.

PINE & EUCALYPTUS TREES ONLY

• If you have pines or eucalyptus on your land or in your garden within 50 metres of your house, you do not need to cut them all down. Being highly flammable trees, if you want to cut them all down and remove their roots on your own land, obviously you can. The law does not stipulate the type of pine tree that you need to manage. However, as all pine tree species (including ornamental pines) are resinous and flammable, they should be included in these fuel management measures…
• Distance between eucalyptus and pine canopies must be at least 10 metres. This is measured from the widest edge of the canopy. If you have a dense stand of these trees you may need to remove some, particularly young saplings, in order to thin them out.
• For pines and eucalyptus up to 8 metres in height, you will need to prune all the branches, hanging bark and dead wood up to 50% of the height.
• For pines and eucalyptus over 8 metres in height, you will need to prune all the branches, hanging bark and dead wood up to 4 metres.
• Easy way to measure tree height
• This includes removing the new leafy growth at the base and on the trunk of eucalyptus that has appeared since the fire.
• The edge of a canopy of a pine or eucalyptus should be at least 5 metres from your house (or other building).
• The canopy must not touch or project over the house (or building) roof.
• If your eucalyptus or pine trees border a road all the above spacing and pruning dimensions must apply PLUS a wide band of not less than 10 metres cleared on either side of the road.

ALL OTHER TREES

• This includes any trees that are not pine or eucalyptus, such as oaks, chestnuts, birch, etc. but not agricultural trees such as olives or grape vines. It is not specified whether fruit trees count as agricultural trees or not – so use your own judgement…if you have a big orange tree very close to the house, for instance, it might be a good idea to prune it back so the edge of the canopy is 5 m away.
• Distance between all canopies must be at least 4 metres. This is measured from the widest edge of the canopy.
• For any trees up to 8 metres in height, you will need to prune all the branches or hanging debris up to 50% of the height.
• For any trees over 8 metres in height, you will need to prune all the branches or hanging debris up to 4 metres.
• The law as it applies to ‘shrubs’ reads as “In the shrub stratum the maximum height of the vegetation shall not exceed 50 cm” and “In the sub-shrub stratum the maximum height of the vegetation shall not exceed 20 cm”. ‘Shrub’ in this case is not your prized blue hydrangea, but the understorey growth immediately beneath trees such as climbers, brambles and bushes etc, then beneath that, grasses and ferns etc. Rather than measuring and pruning it, just remove it all, as recommended by fire protection experts. The aim is to stop a ground fire reaching the tree canopy via all the undergrowth or ladder fuel.
• The edge of a canopy of any tree should be at least 5 metres from your house (or other building).
• The canopy must not touch or project over the house (or building) roof.
• If any other tree borders a road all the above spacing and pruning dimensions must apply PLUS a wide band of not less than 10 metres cleared on either side of the road.

POSSIBLE EXCEPTIONS TO THE LAW

• In instances of trees of special heritage or landscape value, the distance of tree canopy to a house may be less than 5 metres provided there is horizontal and vertical discontinuity of fuels and there is a guaranteed absence of fuel accumulation on the roof.
• Trees of special heritage or landscape value, but NOT eucalyptus or pine, may be exempt from the 10 metre road clearance.
• In areas of public interest, protection zones of national buildings or monuments, trees of special heritage or landscape value or other vegetation protected for conservation or biodiversity reasons, the municipal forest defence committee can approve fuel management criteria.
• The fuel management measures may be waived on request, if as a result of fuel management, there is a significant and substantiated risk to the soil and slope stability of road or railways.

So that is the Portuguese fuel management law as it stands at the moment – February 2018.

More Fuel Management Measures

There are other highly recommended measures of protection against wildfires within your 50 metre zone, which are not specifically addressed in the Portuguese fuel management laws…

• Create additional fuel breaks with strategically placed driveways, paths, patios, parking areas and decks. Particularly make a 10 metre protection area where vehicles can easily access the property – including large emergency vehicles
• Construct perimeter walls with non-flammable materials such as rock, brick or cement  which will reduce fuel loads and create fuel breaks. Water features, pools, ponds or streams can also act as fuel breaks.
• Keep grass cut short and clear fallen leaves, dead branches and pine needles.
• Plant deciduous trees and shrubs (they drop their leaves every autumn) which burn with less intensity than evergreens because they have a higher moisture content when in leaf, a lower fuel volume when dormant, and they typically do not contain flammable oils. Conifers and broad-leaf evergreens contain oils, resins and waxes that make these plants burn with great intensity.
• Remove any dead or weak trees, bushes and logs.
• Remove any small conifer saplings growing between mature trees.
• Tree and shrubs in this zone should be planted in small clusters to break up the continuity of the vegetation across the landscape.
• The idea is to create a lush green, healthy space which is regularly watered and full of ‘firewise’ plants, shrubs and trees.
• Keep a fire extinguisher and simple fire-fighting tools handy such as a shovel, rake, bucket and hoe – ie, so you don’t have to think where you last put them and find a key.

Source: INCF

Now comes the big problem…What if someone else owns uncleaned land which falls within your house fuel management zone? Find out what you can legally do…

Header Photo: Miguel Riopa