Bjorny Bjornstrom

Thanks Clay Bunch. I probably should have explained the system more clearly.

This is a temporary solution until the house is finished. When the house is finished we'll have a wetback and mega hot water cylinder. I think I've got that part under control.

Until then I have a single gravity fed water source. I had imagined I could feed the water through the hot water cylinder and then through the califont. The califont would only be switched on if there is insufficient solar power to heat the hot water cylinder.

We're off grid solar and in the middle of our build. We're currently using a gas califont for hot water. I've been offered a hot water cylinder with a pressure booster pump. I'd like to install it so that when we have the electricity, the solar heats the hot water but if there is not sufficient solar power or we run out of water, the gas califont will kick in (or I can turn it on manually). Does anyone have any ideas on how to do this or even if it's possible?

Luke Mitchell wrote:Not an answer but a question: have you sealed the straw bales in some way, before cladding?

I'm sure you know this but straw bales must be kept absolutely dry to prevent mold. Rodents may well make homes in the bales too, if they can access them. A good, thick lime render will prevent both of these things (assuming a good roof overhand for keeping off most of the rain).

Thanks for the tip. Yes, where the cladding is over straw bales I have done that. The cladding is also used on the north side of the house where we've gone for smaller eaves (to maximise passive solar gain). The north side is also exposed to wind driven rain and, as a consequence, we are not using straw bales on that side.

That's boards with sapwood not whole sapwood boards.

Thanks for the replies. I've still not found an authoritative definitive answer.

I'm going to try to avoid sapwood if possible and a friend suggested putting a couple of sapwood boards in spots where they'll be easy to replace.

I have a small amount of cladding to do on a straw bale house (normally plaster, I know). I have access to a source of Japanese Cedar (cryptomeria japonica) which is the timber traditionally used for yakisugi. The timber I have access to is not 100% heartwood. Most pieces, but not all, have some strips of sapwood on them. Ideally I would use 100% heart but does anyone have any experience with the durability of sapwood in these circumstances? Thanks.

Thanks, I think I've sorted it satisfactorily.

Greetings Permies.

I'm building a non-loadbearing straw bale house. I have a 500L hot water cylinder which needs to sit above a wetback wood stove. I have earth floors and concrete strip footings. The internal wall against which the hot water cylinder will sit is made from 6x2. The question: Does anyone have any guides or ideas as to how to gauge how strong to make the framing for the hot water cylinder? Because it is an earth floor, I was planning on building the platform across a corner so that the weight will bear against concrete in two parts but not on the earthen floor. I was also planning to brace diagonally down to the corner of the concrete footing. I also have the option securing up to the roof framing as well.

I'd be grateful for any pointers.