Form plywood for arch form - which variant?

[MoggeS]

Will form (vault shape) for a concrete slab with a total area of 12m2, 160mm thickness. My question concerns form plywood and the difference between all the variants available on the market. I have quite a few basic boards (12mm, poplar veneer 120g) lying here at home, never used and have been kept dry. Can I use these boards or do I need to acquire others of better quality (like birch)?

 

[justusandersson]

It primarily depends on which radii are relevant. Poplar is related to aspen, which is quite soft. I don't think birch is better. The most flexible type of wood I know of is ash.

 

[MoggeS]

It is not a vault that I am going to cast, but a concrete slab. A bit misleading, but such a form is called a valvform.

 

[justusandersson]

Then it probably doesn't matter that much...

 

[Jonatan79]

The style police announce that arches of all kinds except for brick in wine cellars are prohibited according to Swedish law since yesterday.

 

[Kane]

The style police would like to inform you that arches of all kinds except brick in wine cellars have been prohibited according to Swedish law since yesterday.

Get a grip, that law came in 1984....