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February 6, 2009 at 4:48 am #246961lucy4Member
In our home we have no insulation in the walls and it is concertboard like fibro cladding.So it is costing a lot to us and the enviroment to heat and cool.
I was looking for a cheap ,easy and quick way to solve the problem.
I was thinking of covering the walls on the outside of the house in Cob.That way myself and the kids could do it too.
We did think about cladding in stone but DH would have to do that and he is short on time.
So does anyone have an experience with this?
would it be cheap and easy?
Any tips welcome 😀February 6, 2009 at 6:12 am #392244Reid_alderbooksMember
I’m no expert with cob, but doesn’t it require extra wide roof eaves over it to afford protection from times of excessive rain?February 6, 2009 at 7:17 am #392245drdreadMember
and exceptionally good foundations to take the weight!!!
sawcement another way to go, labour intensive, but less problems with foundations
searching the net is the way to go
mt ben idea is good if you are handy,:D
factor in the cost for your proposal and barter for labour?February 6, 2009 at 11:55 pm #392246RobyneMember
check out th enew governments idae of getting all houses insulated might save you a lot of moneyFebruary 7, 2009 at 12:36 am #392247kiwimamaMember
I don’t think cob would work like that, sorry. It needs to be very thick, it’s heavy, and I think you’d have trouble getting it to key onto the walls anyway. It would probably be easier to start over and build a cob house from scratch!
But you might be able to do something with strawbale. What kind of footings does your house have?
Hmmm … other ideas … If you need more space too, could you add an extension to the side the coldest winds come from? If it was properly insulated, or built from an insulating material like strawbale, it could make a big difference.
Adding more interior thermal mass might make a big difference. If you had space to put in a big masonry wood heater, that would not only heat the house, it would also act as a heat sink when not in use, evening out the temperatures. They burn very clean and wood is the ultimate renewable energy.
I think the idea of gradually recladding is probably the most financially sensible one. Another possiblity could be to apply “false” interior walls with good insulation in them, if you can afford to lose a few inches off those edges of your rooms. That might be sensible if your cladding is in good nick but the interior finish needs redoing anyway.
You could perhaps add some passive design features. eg a vine-covered pergola to the north and some deciduous shade trees east and west might solve the summer cooling problem. If you get cold southerly winds, a thick planting of evergreens to the south would help shelter the house in winter and might make a noticeable difference. Of course, they take time to grow!
🙂February 18, 2009 at 9:13 pm #392248jodieandgeirMember
You can retrofit with straw bales on the outside, but it will require you to build some solid foundations around the existing house – about 450-500mm wide and depth would depend on your soil condition. The straw bales and the render actually do weigh quite a bit, so it needs to be properly done. We did this around a kit cabin we first built (which is now the extra guest room) but had planned to do it all along, so just made the slab wider than the actual cabin. Have a look at this one for the building of the cabin and and this one for the straw bale retrofit. You can also go here for a full overview of all out building activities.
But your best option might be to either take of the cladding and then fit insulation or contact a company that does the spray in insulation where they just have to drill some holes in the wall.
As far as I know with the new government rebate for insulation they are only talking about ceilings, and not walls. But if your ceiling is not insulated, then this is where you should start as the heat loss here would be greater then in your walls.
GeirFebruary 18, 2009 at 9:20 pm #392249hillbilly girlMember
Just a little thought. I lived in a fibro box of a house for several years. flat roof, fibro walls, masonite lining. The extremes in temperature were horrible. Then I insulated the ceiling, but not the walls (I was replacing the roof at the time). Worked well in winter, but in summer it was a horror as the heat build up just couldn’t escape. I had excellent cross-ventilation, and great sea breezes in the afternoons, but it just didn’t seem to do the job. Wall insulation clearly is important to cut the heat. A cheap option might be to attach trellises and grow vines so that the walls are shaded … That way you get fruit as well if you plant the right sort of vines …;)February 20, 2009 at 5:53 am #392250corbMember
If you install air vents in the tops of the walls that will exhaust the hot air.
Planting trees on the west and east sides of the house shades the walls during the sunrise and sunset.
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