we have spoken about the fire rating of our home before. living where we do has a number of benefits, but also one massive potential issue: bush fire. many decisions we have made during the design and build, and the subsequent maintenance, have to do with the fact that we live in the bush, among trees and shrubs that burn really, really well.
as we designed and built the house one of our aims was to ensure we provide fire as little attack surface as possible. one obvious consequence was the choice of non-combustible materials (hempcrete, one might be surprised to hear, does not burn at all) as well as covering any opening that could allow embers to intrude into the house.
gutters are also well known hazards in the event of a bush fire: first of all embers can accumulate in the gatters, and while ours are steel, the material is thin enough to actually melt if too much heat is applied. and then there is the not inconsiderable matter of the two valleys between the differently pitched parts of the roof.
we initially asked the company who built the roof and installed the mesh on the gutters to cover the valleys as well, but they let us know that they couldn’t come up with a solution. to be fair, the angles of the valleys are not 45 degrees, which makes the installation difficult to say the least. the issue, however, is that the valleys are even wider than the gutters, potentially allowing even more embers to accumulate, and potentially get blown under the roof sheeting. this was clearly not something we were willing to entertain, so we had to develop a solution ourselves.
the angles of the valleys made for weird undulations of the mesh between the sides of the roof, but apart from that the installation was actually pretty straight forward. it took nat and i a few hours but we’re pretty happy with the result: we don’t have to fear ember intrusion or accumulation, but the roof can of course still breath and rain water collection isn’t hampered either.
as an aside, leaves and bark from the gum trees can’t get into the gutter and consequently the stormwater pipes either. they are known to colour the water and give it a strange taste, too. all in all it looks like we may have killed a few (proverbial) birds with that particular stone.