Replacing Weatherboards - on stumps - want to go to ground level

[kchambers]

So I have a country property, around the house is cleared - just dirt. Its in area that gets a lot of weathering.... So over the years the weatherboards have rotten quite badly... Time to upgrade and replace.

I am thinking of pulling the weatherboard off, replacing the cladding with vertical James Hardie Oblique cladding - as i really want to modernise the look of the house....  It being a cement sheet base type product I think its perfect for aBushfire Atack Level.

So the house is on stumps which has weatherboards currently around 60cm or more from the ground level - I really want my cladding to go all the way to the ground. Its a bush area - I have found snakes / rodents / foxes / all sorts of animals living under the house, and in the past had wiring chewed etc. So wanting to prevent rodent / animal entry as much as possible.

Yes I understand the need for airflow - I can do that in other ways with grills / even solar fans / to get airflow having fine mesh to stop the uninvited guests.

Hence I originally thought, cement sheet type product - I could take the cladding all the way to the ground. Unfortunately after reading the instalation documention and specification - no it needs to be 140mm or something similar from above ground. I think mainly because of airflow.. . but not wanting to get rising damp on this anyway... Water already runs away from the house there would be very little pooling - but it does get massive rain at times.

Any suggestions on what to do... 

- I could run around with a concrete edge to ensure the ground is slightly higher along the part of where the cladding comes down and meets this instead of ground, and prevent any run of water / pooling of water... But I dont want to be laying lots of concrete runs...

- I could place something like a hardwood sleeper on the ground and have cladding butt against that...

Any other ideas - some PVC edging ?

[JacobZ]

Hi @kchambers,

So, to break it down, you're in a bushfire-prone area, and you are hoping to extend the cladding down to ground level to prevent animals from taking up residence under the house. 

Noting that you are in a bushfire-prone area, it's important that whatever you do is in line with the relevant standards, which are Australian Standard 3959 alongside the recommendations of the National Construction Code Part 3.7.4 - Bushfire Areas. They base their recommendations on specific BAL ratings and offer slightly different recommendations for subfloor encapsulation based on them. Are you aware of the specific BAL rating in your area?

Unfortunately, the Australian Standard is not a free document, and I do not have access to it to interpret, but there is some free information online if you search for Australian Standard 3959.

From what I can see, it looks like there wouldn't be any issue with enclosing your subfloor as long as the materials used comply with the standards for wall construction in your area. The James Hardie Oblique cladding is fine for use in areas with a BAL rating of up to 40, so you would need to confirm that this is the case in your area.

Assuming everything relating to your BAL rating is above board, then you should be ok to install the Oblique cladding as long as the ground clearance is met and the board is adequately supported in line with its installation requirements. I think a hardwood sleeper is likely the way to go to enclose the gap needed for ground clearance, but you would need to ensure that that sleeper is a species of hardwood that is listed as a "Bushfire Resistant Timber" in AS 3959. 

There is some complexity to it, and unfortunately, I don't have all the information required to give a clear-cut answer, but I think I have hit on the key points that need to be considered. Let me know what you think.

Jacob