Are there any very long spans.
Straw bale roof insulation.
A good time to use this roof is obviously when the budget is tight or if you want a larger exposed side of the structure as in a greenhouse or in cooler climates.
This implies that bales r factors would be considerably higher.
In a straw bale house these bales form the walls insulation and framework all in one with some additional support from wooden beams wherever they re necessary.
Make sure it s in good condition no rot termite damage cracked boards etc.
The typical straw bale is bound twice and is approximately 900mm long 350mm high and 450mm deep.
However if you want to use bales you can use an assembly that looks something like this.
If you re wondering what the r value of strawbale construction is then it depends on a few things.
Straw enables vapour permeable walls which are locally sourced and have low impact for construction.
A straw bale is very suitable as infill nonload bearing insulation for timber frame buildings with either an external render or timber rain screen finish.
The density of the straw how long the straw itself is as well as the moisture content how well the gaps are filled between bales and other things like how it s stacked.
Straw bale construction is a building method that uses bales of straw commonly wheat rice rye and oats straw as structural elements building insulation or both.
This construction method is commonly used in natural building or brown construction projects.
On end or flat.
Personally i stick with light weight insulation materials in the roof and leave the bales for the walls.
A bale is 360mm deep.
Owen geiger yes you can use straw bales as roof insulation.
The two layers of batts and 3 of rigid foam andrew describes would be about 240mm deep for r57.
First you need to check the strength of your roof system.
For straw bale this can pose a problem in keeping the walls free from direct moisture.
Strawbale insulation is tightly packed and 18 thick.