hire out HVAC though
The four most common causes of exposed fasteners backing out are:
- Incorrect initial installation. Overdriven screws damage the fibres in either the wood or sheet substrate reducing holding power.
- Ice dams can, as you say, put pressure on the heads.
- Too few fasteners combined with light gauge roofing can allow wind to create repeated movement in the panels slowly working them loose.
- Moisture in the furring or plywood reduces its holding capacity.
The best solution, but for a variety of reasons not the most palatable, is to replace the roof with a concealed fastener snap-lock roof.
Barring that, and given that the substrate is in good shape, I'd replace all the gasketed fasteners with ones of a much larger diameter.
I've also heard that the expansion and contraction of through fastened steel due to temperature changes can work the screws loose. This is exacerbated when the substrate is thin plywood or osb. Solid wood strapping or purlins are the preferred substrate.
AnnaLea Kodiak wrote:
I may be misinformed about earthbags, I know they operate on the property of thermal mass as opposed to insulation, but I figured we wouldn't need insulation if the thermal was thick enough. I thought that if we were heating or cooling internally, the earthbags would retain that temperature and then radiate the heat or cool, reducing costs. Is this not true? Would it just go straight through and be lost to the outdoors? I may be misunderstanding how thermal mass works.
And in winter, you can close the bottom vents and run a fan down a duct from the top to the bottom,