Insulation facts - website or feedback

[henward]

wondering, what is better insulation.

wool stuff or polystyrene sheets.

say, i have a wall, i want to fill it and cover it with ply.

what will be better to use, solid sheets of poly or wool, say same thickness, uncompressed.

i know that industrial cold stores are 50 to 60mm of poly sandwiched between alluminium sheets.

[hovmoller]

There's not much difference in insulation performance between average polystyrene and mineral wool. Around the same R-Value for the same thickness.

If you are filling in between framing etc. then wool is easier to get a better fit without gaps etc.

[henward]

yeah, between the frame and i will put ply to cover it up.

i have much surplus poly, i want to use wool too.

but dnt want to waste poly lol

[Warren]

You could use both. Roughly stuff the gaps with chunks of poly and fill the gaps with wool. Then you use up all the spare poly and get to use wool as well - bonus!!

[jackp]

For the ceiling of my old fish shed I used fibreglass insulation between the rafters then lined with ply and glued poly to the ply. Possibly overkill, but why not?

[Ira]

Pretty easy to build a hot wire foam cutter

http://www.instructables.com/id/Hot-wire-foam-cutter/

If you have big pieces you can cut them down the to the right size and slot them in, stuff any inconvenient gaps with wool.

[David R]

Poly is much nicer to work with than Batts (although you can get that greenstuff polyester wool which is less irritating), but as Hovmoller said you really want a completely snug fit so there are no gaps, so wool is far better for using between framing.

[henward]

i can definiately make them snug.

and stuff them too.

id otn wanan waste the poly but if the garage is big, i will have to get other stuff anyways so the wolly green stuff may be it.

might do both.

might focus on both for ceiling, get best of both worlds, and wolly stuff on the sides of the building.