Building a FireSmart custom home on a forest-edge lot in Burnaby

The City of Burnaby installed a wildfire detection system on Burnaby Mountain this spring: smoke cameras on rooftops and ground sensors in the forest, watching what the City calls "one of the city's largest forested areas, located along the urban-wildland interface." A full-scale emergency exercise on the mountain is planned for 2027.

If you own a lot along that edge, or one backing onto Central Park, Deer Lake Park or the Forest Glen greenbelt, the City has told you what it thinks the risk is. The question for a custom home is what to do about it in the drawings.

Three zones, and the first one does most of the work

FireSmart BC splits the ground around a house into a Home Ignition Zone with three bands. The Immediate Zone runs from the wall out to 1.5 metres. The Intermediate Zone runs from 1.5 to 10 metres. The Extended Zone runs from 10 to 30 metres.

Embers, the burning debris a fire throws ahead of itself on the wind, land on and around the building before any flame front arrives, and FireSmart's guidance is built around stopping them. That is why the first band is the one that matters. FireSmart's instruction for it is blunt: choose non-combustible building materials, clear vegetation and combustible material down to mineral soil, cover the ground with gravel, brick or concrete, and keep woody shrubs and trees out of it.

On a custom home that translates into a strip of gravel or paving at the base of every wall, with the planting beds starting outside the 1.5 metre line. Bark mulch, the default finish in most Lower Mainland gardens, stays out of that strip. Fire-resilient plantings are a design choice for the 1.5 to 10 metre band, and in Burnaby the landscape designer and the builder have to agree on it early because it changes the grading plan.

Cladding: what touches grade, and what faces the trees

FireSmart BC's Begins at Home guide ranks siding plainly. Stucco, metal siding, brick, concrete and fibre cement offer superior fire resistance. Logs and heavy timbers are reasonably effective. Untreated wood and vinyl offer little protection.

The program's construction checklist adds the detail that matters most at the wall base: exterior siding should stop at least 15 centimetres above grade, with the exposed foundation wall below it non-combustible. Embers collect at the base of a wall the same way leaves do. A cedar board that runs down to the mulch is a wick.

This is where we make the argument that FireSmart and good envelope practice agree. On the Wet Coast the BC Building Code already requires a rainscreen behind the cladding, and the cladding choice on our Burnaby builds is fibre cement or metal panel more often than not. Both are on FireSmart's preferred list. Cedar still has a place on a forest-edge house, as an accent under a covered entry or on an upper storey away from the trees, over a non-combustible base. What we avoid is running it to grade or wrapping the wall that faces the forest in it.

The rainscreen brings one detail that needs care. The drainage cavity behind the cladding has to vent at the bottom and the top, and the checklist speaks to exactly that case: where gaps are built into the siding to let a rainscreen wall dry, any gap larger than 3 millimetres gets 3 millimetre non-combustible metal screening. So the cavity closures at the base of the wall and under the roof edge are a non-combustible perforated closure with openings under that size, which lets the wall dry and keeps embers out. It is a part the siding installer needs to have on the truck before the first course goes up.

Roofing and the vents in it

The roof is the largest surface embers land on, and FireSmart BC calls for fire-rated roofing, the Class A, B or C ratings, with metal, asphalt shingle, clay and composite tile all on the list. Untreated wood shakes are called out for what they are: combustible material full of crevices for embers to sit in. The construction checklist goes further and asks for a Class A rating on both the covering and the underlayment beneath it.

Between standing-seam metal and asphalt shingle, the two roofs we compare most on the coast, both can carry a Class A rating from the manufacturer. On a forest-edge lot the metal roof earns extra points for shedding needles and moss, because a roof that holds a mat of dry debris in its valleys is a roof with fuel on it.

Vents are the weak point. Attic and crawlspace vents exist to move moisture out, and the BC Building Code requires them, but each one is an opening embers can enter. FireSmart's answer is to screen every vent with 3 millimetre non-combustible wire mesh, and to close open eaves with properly fitted soffits and fascia so heat and embers cannot reach the attic through the rafter bays. The checklist also asks that soffit vent perforations be smaller than 3 millimetres in any direction, that gable-end vents be avoided, and that exhaust and intake terminations on the walls be non-combustible and screened. Gutters get metal mesh guards so they do not fill with needles.

None of this changes how the house looks. It changes the part number on the vent order and the soffit spec, which is why it has to be in the drawings rather than left to the roofer.

Windows and doors

Radiant heat from a fire in the trees breaks glass before flame ever reaches the wall, and a broken window is an open door for embers. FireSmart recommends tempered, double-glazed windows and notes that single-pane glass offers little resistance. Windows on a new Burnaby custom home are already double or triple glazed to meet the energy target, so the change here is specifying tempered glass on the faces that look at the forest, and confirming that exterior doors, including the garage door, are fire-rated and seal properly at the frame.

Decks: the part that faces the forest

Decks and covered outdoor rooms on a forest-edge lot almost always face the trees, because that is the view. They also sit in the 1.5 to 10 metre band and are made of the material most likely to catch.

The FireSmart construction checklist asks that a deck within 10 metres of the house have a continuous ignition-resistant or non-combustible top surface, that the space under it be cleared of vegetation, graded with non-combustible material and enclosed with 3 millimetre metal screening, and that a non-combustible break separate the deck surface from combustible siding where the two meet. The homeowner's manual says the same thing in fewer words: sheath the base of decks and balconies with fire-resistant material and remove the fuel underneath.

For our Burnaby deck builds on these lots that means a composite or aluminum deck surface, or fire-retardant-treated wood, closed skirting with screened vents, gravel under the deck instead of bare ground, and metal rather than wood for the railing where the deck faces the forest. A wood fence tied to the house is the other classic path for fire to arrive at the wall, and FireSmart wants a metal gate or a full break of at least 1.5 metres between a wood fence and the exterior wall.

Embers do not care what the house cost. They care what is in the first metre and a half.

Icon Projects Team

Defensible space meets the Burnaby Tree Bylaw

This is where a Burnaby forest-edge lot gets complicated.

FireSmart's Extended Zone guidance, for the 10 to 30 metre band, asks owners to selectively remove evergreens so there is at least 3 metres of horizontal space between tree crowns, and to prune lower branches to 2 metres from the ground. On a treed lot that is real thinning.

The Burnaby Tree Bylaw protects any tree 20 cm or more in diameter on a property under a development application, which is every custom home build. Removing one takes a tree cutting permit, and each removal comes with replacement trees: one for a tree between 20.3 and 30.5 cm, two between 30.5 and 61 cm, three at 61 cm and up, or cash-in-lieu to the City's tree reserve fund where there is no room to plant. The City's page lists the reasons it issues permits, including trees that are unhealthy, structurally unsound, in conflict with utilities or damaging structures. Wildfire spacing on its own is not on that list, and neither is shade or view.

So the two goals meet on the tree plan. Every protected tree on the lot is surveyed, an arborist assesses each one, and the plan submitted with the building permit shows which trees stay, which come out and where the replacements go. Where a tree in the Extended Zone is healthy and protected, it stays and gets pruned to FireSmart's 2 metre height, which the bylaw does not restrict. Where a tree is a candidate for removal on the City's own criteria, the removal also opens crown spacing. Replacement trees go in as deciduous species placed outside the 10 metre band, because a maple at 15 metres is a different fire risk than a hemlock at 3. The tree bylaw's effect on a custom home is a permit-stage conversation on every Burnaby lot. On a forest-edge lot it is also a fire-safety one.

The same lot in Coquitlam or on the North Shore

Coquitlam states that a large portion of the city is wildland-urban interface land and publishes a guide called Building and Landscaping Recommendations for Wildland/Urban Interface Areas, covering development design, construction materials and landscaping. It sends residents to firesmartbc.ca for the rest and tells them to consult local bylaws and registered covenants on materials before building. A Burke Mountain lot in Coquitlam gets the same three-zone treatment as a Burnaby Mountain lot, with the added step of checking the title for a covenant that may already dictate the roof and siding.

The District of North Vancouver goes further. It has a Wildfire Hazard Development Permit Area covering every property in its forested wildland-urban interface, and a new or replacement house inside it needs a development permit supported by a signed report from a qualified professional. We have not found an equivalent in Burnaby. On a Burnaby forest-edge lot the measures in this post are ours and the owner's to specify, which is exactly why they need to be in the drawings before the permit goes in.

Insurance, stated generally

We do not speak for insurers and we do not quote premiums. Every insurer sets its own underwriting terms for interface properties, and those terms change. What a FireSmart build gives an owner is a documented record: a Class A roof, non-combustible cladding at the base, screened vents, a cleared and gravelled 1.5 metre zone, and an arborist's tree plan on file with the City. That record is worth putting in front of a broker before the policy is placed. Ask what their underwriting looks at for a forest-edge address, and ask it while the roof and siding are still a line on a spec sheet.

Everything in this post can be built into a modern house without anyone noticing it from the street. The gravel strip reads as a clean edge. The fibre cement base reads as a plinth. The screened vents and closed soffits are invisible. The only visible decision is what the deck is made of, and on a lot that looks into the trees, that is the decision to get right.

Frequently asked questions

Which parts of Burnaby are on the wildland-urban interface?

The City of Burnaby describes Burnaby Mountain as one of its largest forested areas, located along the urban-wildland interface, and it installed a wildfire detection system there in 2026. Lots backing onto Burnaby Mountain, Central Park, Deer Lake Park and the Forest Glen and Burnaby Lake greenbelts share the same condition: forest on one side of the property line. We have not found a Burnaby equivalent of the District of North Vancouver's wildfire hazard development permit area, so on a Burnaby lot the FireSmart measures are the builder's and owner's choice to write into the drawings.

What is the FireSmart home ignition zone?

FireSmart BC divides the area around a house into three zones. The Immediate Zone runs from the wall out to 1.5 metres and is meant to be non-combustible. The Intermediate Zone runs from 1.5 to 10 metres and is managed so fire cannot travel across it to the house. The Extended Zone runs from 10 to 30 metres and is thinned and pruned to reduce fire intensity before it gets close.

What should be in the first 1.5 metres around a house on a forest-edge lot in Burnaby?

Nothing that burns. FireSmart BC calls for clearing vegetation and combustible material down to mineral soil in the Immediate Zone and covering it with gravel, brick or concrete, choosing non-combustible building materials for the walls, and keeping woody shrubs and trees out of the band entirely. On our Burnaby builds that becomes a gravel or paved strip at the base of the wall, with the planting beds starting outside it.

Is cedar siding a problem on a forest-edge lot in Burnaby?

FireSmart BC lists stucco, metal, brick, concrete and fibre cement as the siding materials with superior fire resistance, rates logs and heavy timber as reasonably effective, and says untreated wood and vinyl offer little protection. Cedar can still appear on a forest-edge house as an accent above a non-combustible base. What we avoid is running it down to grade or wrapping the whole wall facing the trees in it.

What is an ember-resistant vent and does a new house in BC need one?

An ember-resistant vent uses non-combustible construction and a screen of 3 millimetre or finer metal mesh so wind-blown embers cannot pass into the attic, the crawlspace or the wall cavity. FireSmart BC recommends screening every vent this way and closing eaves with properly fitted soffits. The BC Building Code sets the ventilation an attic and crawlspace need, and the mesh and closed eaves are a specification we add on top of that, so on a Burnaby lot they go into the drawings as a choice.

How does the Burnaby Tree Bylaw affect FireSmart tree spacing?

On a property under a development application, the Burnaby Tree Bylaw protects any tree 20 cm or more in diameter, and removing one requires a permit and replacement trees on a ratio that rises with the size of the tree removed. FireSmart's Extended Zone guidance asks for at least 3 metres between evergreen crowns and lower branches pruned to 2 metres. The two are reconciled on the tree plan that goes in with the building permit, with an arborist choosing which trees stay, which come out and where replacements go.

Does a forest-edge lot in Coquitlam have different wildfire rules than Burnaby?

Coquitlam states that a large portion of the city is wildland-urban interface land and publishes a guide called Building and Landscaping Recommendations for Wildland/Urban Interface Areas covering design, construction materials and landscaping. It also directs residents to firesmartbc.ca and tells them to check local bylaws and registered covenants on materials before building. Burnaby has no equivalent published guide, so the FireSmart BC manual is the reference we use on both sides of the boundary.

Will building to FireSmart standards affect home insurance on a Burnaby forest-edge lot?

Insurers set their own terms and we cannot speak for any of them. What we can say is that a house with a Class A roof, non-combustible cladding at the base, screened vents and a cleared 1.5 metre zone is a house with a documented record of fire-resilience measures, and that record is worth having in hand when a policy is placed or renewed. Ask your broker directly what their underwriting looks at for interface lots before the design is locked.