It's soon time to insulate the intermediate floor in my old farmhouse, which we've been renovating with building conservation in mind.
We have underfloor heating on both floors, so I assume it will primarily be about sound insulation (feel free to point out if the insulation might serve another function while both floors are in use).
We have some surplus from the house's additional insulation that I hoped to use, so which of these materials do you think can be used with decent results?
- Cellulose insulation (iCell)
- Foam glass gravel (Foamit 20)
- Linen insulation (Isolina)
The thickness of the insulation can be 150-200 mm. Anything in particular to keep in mind regarding the insulation above the bathroom? I'm probably forced to buy more insulation, what should I invest in then?
We have underfloor heating on both floors, so I assume it will primarily be about sound insulation (feel free to point out if the insulation might serve another function while both floors are in use).
We have some surplus from the house's additional insulation that I hoped to use, so which of these materials do you think can be used with decent results?
- Cellulose insulation (iCell)
- Foam glass gravel (Foamit 20)
- Linen insulation (Isolina)
The thickness of the insulation can be 150-200 mm. Anything in particular to keep in mind regarding the insulation above the bathroom? I'm probably forced to buy more insulation, what should I invest in then?
Know-It-All
· Västra Götaland
· 12 296 posts
For soundproofing, you want mass, where, for example, sawdust is good.
Foamed glass aggregate has a density comparable to sawdust, around ~200-250 kg/m3.
According to p.13 in this document, it should work reasonably well, anyone with experience? http://www.foamit.fi/wp-content/uploads/2016/10/foamit_husbyggnad_SWE_web.pdf
According to p.13 in this document, it should work reasonably well, anyone with experience? http://www.foamit.fi/wp-content/uploads/2016/10/foamit_husbyggnad_SWE_web.pdf
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You are absolutely right that the insulation only dampens sound and doesn't fulfill any thermal insulating function. However, soundproofing is even more important.
An "empty" intermediate floor becomes like a drum. When you walk on it, it's like hitting a drum. The steps set the wood in vibrations that are amplified in the soundbox that is created.
Therefore, you have two main challenges:
1. Stop the wood from vibrating
2. Dampen the sound in the soundbox.
Now, wood vibrates very well, ask any instrument maker, so it takes some effort to stop it from doing so.
For instance, if you could use sand, it would be great, but of course, it becomes too heavy and absorbs moisture. Concrete is okay but can transmit structure-borne sound, to take another extreme example.
But more realistically, it's about accepting the situation when it comes to the wood and instead dampen the sound in the resonance box. Regular stone wool or glass wool is usually used effectively, so linen insulation is totally fine.
I have no experience with foam glass granules, but it seems to be the best option of the three. I would strongly advise against cellulose.
An "empty" intermediate floor becomes like a drum. When you walk on it, it's like hitting a drum. The steps set the wood in vibrations that are amplified in the soundbox that is created.
Therefore, you have two main challenges:
1. Stop the wood from vibrating
2. Dampen the sound in the soundbox.
Now, wood vibrates very well, ask any instrument maker, so it takes some effort to stop it from doing so.
For instance, if you could use sand, it would be great, but of course, it becomes too heavy and absorbs moisture. Concrete is okay but can transmit structure-borne sound, to take another extreme example.
But more realistically, it's about accepting the situation when it comes to the wood and instead dampen the sound in the resonance box. Regular stone wool or glass wool is usually used effectively, so linen insulation is totally fine.
I have no experience with foam glass granules, but it seems to be the best option of the three. I would strongly advise against cellulose.