ᐅ Reuse Styrodur 3035 CS insulation from a demolition?

Created on: 27 May 2015 19:12
L
Legurit
Hello everyone,

Today, to our surprise, we discovered a large pile of used extruded polystyrene (XPS) insulation boards on our property. I’m a bit puzzled… I assume these are intended for the foundation insulation. It looks somewhat like they might be from a building demolition. Is it acceptable to reuse them like this? Some of the boards are quite damaged… On the other hand, if they fully serve their purpose, it would also prevent new production because of us.

Thanks for your input.
Good luck!

Green insulation boards stacked in front of an exterior wall; wooden battens on top, red poppies in front.

Several stacks of green insulation boards outdoors, rust stains, grass in front.

Stack of greenish-white styrofoam insulation boards outdoors next to a wall, surrounded by weeds.
S
Sebastian79
27 May 2015 20:51
Why use expanding foam?

As mentioned, expanding foam has no place there at all...
B
Bauexperte
27 May 2015 20:53
Lexmaul79 schrieb:

As mentioned, expanding foam has no place there...
It will not be expanding foam that is used in this case. However, the original poster is familiar with this term.

Regards, Bauexperte
S
Sebastian79
27 May 2015 20:55
He does say that his construction manager wants to use expanding foam...

And it's good that he knows — I asked you.
L
Legurit
27 May 2015 22:32
In the structural calculations, it states: "All strip foundations are to have continuous reinforcement consisting of two ø10 bars placed at the top and bottom, unless otherwise specified with higher requirements."
The builder has already been informed about the foam sealant – there are foam sealant residues on the panels as well, aren't there?
B
Bieber0815
27 May 2015 23:15
The contractor should provide you with a written confirmation that the structural engineer has formally confirmed that the steel-fiber reinforced concrete is equivalent to the specified reinforced concrete ring beam.

Regarding the insulation, I would check (or have it confirmed in writing) that the thermal conductivity rating is the same. Alternatively, ensure that the overall agreed performance is met (thermal conductivity rating multiplied by thickness). You should be able to negotiate a significant discount. For political or tactical reasons, it might be better to insist on “new” materials. Otherwise, more components might come from the demolition house, perhaps even the bathtub.

Building a house really is an adventure.

Be sure to share the names of the companies involved here!
B
Bauexperte
28 May 2015 00:34
Good evening,
Lexmaul79 schrieb:

And good that he knows it – I asked you.
That must have escaped me; I’m not a specialist in insulation.

If I remember correctly, the insulation under the base slab needs to be encased; this will logically be done at the height of the future floor slab plus insulation. I also believe the boards themselves have a tongue-and-groove edge. If glued, it is probably only the joints and only spot-glued. However, I don’t know what type of adhesive that is or its exact name. Usually, you’ll find regulations for this in the DIN standard haumichtot, probably under building waterproofing. The requirements for a membrane beneath the insulation are also covered there.

We will begin earthworks in two weeks for a 55 construction project. After that, my memory will be refreshed and hopefully clearer. We don’t currently build many 55 construction projects.

Regards, Bauexperte