We are about to build an upper floor on our house, and I'm thinking about how we should construct the intermediate floor to get as rigid and quiet a floor as possible (we will have the kitchen on the upper floor).
I suspect that the best way is to have an air gap between the floors, but then it might practically involve two floor structures? Does anyone have any ideas?
I suspect that the best way is to have an air gap between the floors, but then it might practically involve two floor structures? Does anyone have any ideas?
Tool enthusiast
· Stockholm
· 1 399 posts
You don't need to build two floor structures. However, it is desirable to achieve thickness in the floor structure dimension. When constructing soundproof structures, all building elements contribute to the final reduction value.
Focusing on the floor structure as part of the construction, the three crucial parameters that contribute are; MASS, AIR GAP, and DECOUPLING. The higher the "value" of these parameters, the better the conditions for achieving a sound-reducing construction. This can be calculated, and there are practical applications that can be advantageously used in non-critical executions.
Since there is already a floor structure, it can be reinforced to increase the air gap. The compartments are filled with loosely packed "light" insulation (20 - 30 kg/m3) up to 2/3. On top of the floor structure's joists, impact sound strips like sylomer/polyurethane are placed, providing the decoupling function in the floor structure. On top of this, floating floorboards, or even better, Ceminwood, are laid. On top of this, two layers of glued and screwed floor gypsum (not needed with Ceminwood) are added. On top of this, the final floor covering.
Note! It is incredibly important that the entire floating floor structure has no rigid connection to surrounding walls, penetrations, etc.
With this procedure, you don't need to make any changes to the existing ceiling in the floor below.
Edit: Remember to seal around all gaps and penetrations with durable elastic sealant.
Focusing on the floor structure as part of the construction, the three crucial parameters that contribute are; MASS, AIR GAP, and DECOUPLING. The higher the "value" of these parameters, the better the conditions for achieving a sound-reducing construction. This can be calculated, and there are practical applications that can be advantageously used in non-critical executions.
Since there is already a floor structure, it can be reinforced to increase the air gap. The compartments are filled with loosely packed "light" insulation (20 - 30 kg/m3) up to 2/3. On top of the floor structure's joists, impact sound strips like sylomer/polyurethane are placed, providing the decoupling function in the floor structure. On top of this, floating floorboards, or even better, Ceminwood, are laid. On top of this, two layers of glued and screwed floor gypsum (not needed with Ceminwood) are added. On top of this, the final floor covering.
Note! It is incredibly important that the entire floating floor structure has no rigid connection to surrounding walls, penetrations, etc.
With this procedure, you don't need to make any changes to the existing ceiling in the floor below.
Edit: Remember to seal around all gaps and penetrations with durable elastic sealant.
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Incredibly good answer! I am not entirely familiar with all the materials, but I will read up more.
Floating floors sound a bit scary, though. Since I am extremely interested in music, I need incredibly stable floors to get the speakers to perform at their best. But if I understand you correctly, that's how we achieve the air gap.
It is likely that we need to replace the bjälklaget anyway since the kitchen and WC will be going on the upper floor.
Floating floors sound a bit scary, though. Since I am extremely interested in music, I need incredibly stable floors to get the speakers to perform at their best. But if I understand you correctly, that's how we achieve the air gap.
It is likely that we need to replace the bjälklaget anyway since the kitchen and WC will be going on the upper floor.
Tool enthusiast
· Stockholm
· 1 399 posts
If you want to achieve a good listening environment where the speakers will "perform to the max," it primarily involves good room acoustics (not to be confused with soundproofing here). This mainly means a good frequency response and an even decay (reverberation time). The more you soundproof the construction, the bigger problems the listening room will exhibit, especially in the bass.
As for soundproofing, the chain is never stronger than its weakest link, i.e., walls, doors, etc., need to match each other in Rw (sound reduction). The construction solution I suggested above demonstrates the principle itself. If you increase the mass of the floating floor (e.g., with ceminwood) and the air gap, the sound reduction increases.
In the construction of sound studios, for example, two layers of ceminwood with damping glue in between are often used, resting on rubber isolators. For more critical installations, a concrete slab is cast to rest on springs - yes, you get the principle.
Edit: The impact noise strips in polyurethane are not to be confused with underlay foam and similar products.
As for soundproofing, the chain is never stronger than its weakest link, i.e., walls, doors, etc., need to match each other in Rw (sound reduction). The construction solution I suggested above demonstrates the principle itself. If you increase the mass of the floating floor (e.g., with ceminwood) and the air gap, the sound reduction increases.
In the construction of sound studios, for example, two layers of ceminwood with damping glue in between are often used, resting on rubber isolators. For more critical installations, a concrete slab is cast to rest on springs - yes, you get the principle.
Edit: The impact noise strips in polyurethane are not to be confused with underlay foam and similar products.
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Now I have had the opportunity to read a bit more about the products you mentioned, Björn. I hadn't initially intended to bring up the audiophile aspects here, but in this particular matter, I am afraid there might be a bit of a contradiction.
The thing is, I want to combine my listening room with the living room that faces a kitchen in an open floor plan. On the ground floor, we will have bedrooms, and I am used to listening LOUD.
I am often in the basement listening to what sounds spread downwards in the house, and not surprisingly, it is footfall noise and bass from the music. My thought was that the very lowest frequency bass might be difficult to manage, so I need to focus more on footfall noise.
Currently, as I am playing on a pair of large floor-standing speakers, my idea was to build as stable a floor as possible. The plan is also to embed underfloor heating beneath the floor, but maybe that's not a problem even if you decouple the overfloor? Perhaps it's even a plus for getting the floor really stable?
How do you suggest solving the decoupling from walls and skirting boards? Do you leave a small gap in between?
The thing is, I want to combine my listening room with the living room that faces a kitchen in an open floor plan. On the ground floor, we will have bedrooms, and I am used to listening LOUD.
I am often in the basement listening to what sounds spread downwards in the house, and not surprisingly, it is footfall noise and bass from the music. My thought was that the very lowest frequency bass might be difficult to manage, so I need to focus more on footfall noise.
Currently, as I am playing on a pair of large floor-standing speakers, my idea was to build as stable a floor as possible. The plan is also to embed underfloor heating beneath the floor, but maybe that's not a problem even if you decouple the overfloor? Perhaps it's even a plus for getting the floor really stable?
How do you suggest solving the decoupling from walls and skirting boards? Do you leave a small gap in between?
Not a brand-new thread, but since we're in a similar situation, I thought I'd see if I could get some advice.
We're planning to lay solid pine flooring on floor joists spaced 40 cm apart on the upper floor, but are worried about poor sound insulation. We want to follow Björn Melander's excellent guidance above, but wonder the following:
Can standard floor gypsum be used instead of ceminwood on the joists? I realize it will be worse, but easier to get hold of, etc. I realize that floor gypsum doesn't carry directly on joists, but the pine floor will be on top and should take care of the load-bearing capacity.
So: joists + sound insulation strips + floor gypsum + felt paper? + screwed pine floor through the gypsum down into the joists.
Could that work? Or is the entire effect negated by the screws down into the joists?
Thanks in advance
We're planning to lay solid pine flooring on floor joists spaced 40 cm apart on the upper floor, but are worried about poor sound insulation. We want to follow Björn Melander's excellent guidance above, but wonder the following:
Can standard floor gypsum be used instead of ceminwood on the joists? I realize it will be worse, but easier to get hold of, etc. I realize that floor gypsum doesn't carry directly on joists, but the pine floor will be on top and should take care of the load-bearing capacity.
So: joists + sound insulation strips + floor gypsum + felt paper? + screwed pine floor through the gypsum down into the joists.
Could that work? Or is the entire effect negated by the screws down into the joists?
Thanks in advance
Yes, our construction is nearing its end and I'm beginning to realize that the issue of sound is not easy to answer. It depends entirely on what you want to isolate from. What will you use the upper floor for? What kind of ceiling is there on the lower floor?
Want to avoid getting noise such as footsteps from the upper floor. Children's room upstairs, dining room underneath ;-)
We are planning to redo the ceiling on the lower floor, and we were considering drywall screwed to furring, but we are open to other solutions if there are more suitable options from a soundproofing perspective?
We are planning to redo the ceiling on the lower floor, and we were considering drywall screwed to furring, but we are open to other solutions if there are more suitable options from a soundproofing perspective?