A client recently joined Elite Caulking with a sensitive question about caulking techniques related to acoustic insulation, with an initial answer, he extended his questioning to the use of EXPansive foam PU insulation.
Here is a summary of the exchange of words:
I have windows to change in a room for which I am doing renovations. There are large fixed panels in the same frame as the opening flaps.
How do I make sure I have good sound insulation?
- An expansive seal mark?
- A silicone brand?
- Injected polyurethane foam?
- An acoustic contractor?
- Or maybe just laying tips?
Shawn’s response,“Mr. Elite Caulking”
Choose quality windows
The most important is the glazing. At a minimum, provide a 10/16/4 FE-argon.
The joining (also known as caulking) and the installation must meet the specifications of DTU 36.5.
There is not typically a specific seal for acoustics, from the moment the seal is designed and implemented to ensure perfect air and water sealing, it will be suitable for acoustics.
This is, for example, a type of seal perfectly suited for a renovation installation with excellent ISO-BLOCO Max 600 acoustic performance: http://www.iso-chemie.fr/
It is a self-expanding, waterproof and air-tight foam seal that does not require a silicone seal.
There is another brand: ILLMOD 600 by Tremco Illbruck: http://www.tremco-illbruck.fr/produits/02384_index.html
Be careful especially no foam PU aerosol can,it is also forbidden in the DTU 36.5 in caulking product.
Do you know why bomb PU foam is banned
I’ve seen a lot of poser put in by arguing that the performance is better?
The expansive foam does not guarantee the air and water sealing between the wall and the sleeper of the new carpentry or between the old sleeper and the new sleeper in case of a renovation installation on existing sleepers and it is precisely to ensure this function where it is prohibited.
This function of air and water sealing is technically referred to as caulking.
The PU aerosol foam is only perfect for providing additional thermal insulation and filling the space between the dubbing and the new sleeper because it has an excellent insulating power indeed better than glass wool for example.
To put it simply, if you use PU foam in aerosol instead of glass wool, everything is fine. Conversely, if you use it instead of a silicone seal on a seal background or instead of a pre-compressed impregnated foam strip, then you have it all wrong because it is not waterproof.
But doesn’t silicone provide air and water sealing? to supplement the injected PU foam?
No, silicone is only used in waterproofing on the outside
and only on a foam seal background, to ensure the seal between two flat faces at least 5mm apart.
It must be continuous, perfectly regular and perfectly smoothed after being extruded carefully.
In addition, it must be compatible with the materials of both supports and not out of date.
The foam seal bottom is used only to limit the thickness of the silicone putty during extrusion and then allow the compression of the putty during smoothing to have a good grip on the 2 supports.
Once the silicone putty is reticulated, the foam seal bottom is no longer useful.
PU aerosol foam is ONLY indoors at the dubbing level and for thermal insulation without any waterproofing function.
PU aerosol foam with silicone is not put on top because PU aerosol foam is not intended to serve as a seal background for a silicone putty. Irregularities caused by the expansion of the foam would not ensure a perfectly regular silicone putty seal consistent with DTU 36-5.
Besides it is forbidden in the DTU 36-5.9.6
A caulking between large work and sleeper of the window by injection of expansive foam does not meet the waterproofing requirements described and ensure its durability.