soundproofing an attic floor, under the yellowtongue

[Nixolus]

I want to lay yellowtongue floor panels over my roof joists, to floor the attic space. The question is what can I do to reduce noise transfer to the rooms below. I'm considering rubber strips over the roof joists, or hard closed cell foam (like the blue stuff campers sleep on, but denser). Have you heard of this kind of thing before? is there a better solution?

I'd love to hear from anyone who has done an attic conversion.

* note I want to lay a floor on top in the future, probably timber. I will not be using carpet at all.

[Larry McCully]

if you contact REGUPOL on the web, you will discover a product for your application.

[Larry McCully]

www.regupol.com.au

[echnidna]

Are your ceiling joists strong enough to also be used as floor joists?

[Nixolus]

Thanks larry McCully, I'll check that out.

Bob Thomas, I sure hope so. The roof joists they installed 100 years ago were pretty decent. I am having an engineer up to look it over anyway though.

[Gaza]

You will find that you will need to re frame the roof to make the joist into floor joists plus add support for the stair case (if Any.

In regard to the sound proofing Regupol K225 (5mm rubber) is option when cut into strips and glued to joists then sheet flooring is fixed ontop of this. For a proper job no fixings should be used so there is no physical connection. (i would screw fix if my place and glue). The celling cavity should be filled with a high grade acoustic insulation ie rockwool.

Your idea of the poly based acoustic material similar to floating flooring underlay would also work well but degrade over time thus regupol being a better but more expensive option.

[echnidna]

If you install new floor joists keep them clear of the ceiling joists.
This will reduce noise transmission.
Using sound insulation in the cavity will alo help

[Pulse]

also consider the ceiling, resilient mounts with new furring channel and thicker plasterboard all help,

.....or how about just telling people to shut up, a long walking stick so you can tap the ceiling should do the trick.

[Nixolus]

"You will find that you will need to re frame the roof to make the joist into floor joists"

Gaza, what do you mean?

[Greg Q]

What he means is a floor joist is typically two or three times deeper in section than a ceiling joist. New joists will have to run all the way to the wall plates, and be fixed there using approved framing methods. Quite often the pitch of the roof and small overhangs mean that there is insufficient space (between the plates and the existing roof framing) directly over the wall plates to run the new joists.

I performed the same improvement to my last house. We ended up raising the roof since it was only an additional week's work and not much money in materials. I will caution you that not all walls and foundations have enough extra beef to take the addition of a full extra story.

One other thing: Your engineer may find load bearing walls within the footprint of the building's dimensions. If this is the case, you might be able to run new joists across a partial span of the attic, and keep the existing roof. (this would ideally mean that you get (say) the middle half of the attic space as useable. An attic ladder is a good solution to the staircase problem.

Greg

[Nixolus]

Well thanks for all the suggestions, I am rethinking my sound dampaning ideas, and I'll wait till the engineer has been to decide on the roof joists.

For sure I'll be back.

[Nixolus]

Well the Engineer has been and he is of your opinion. I am to put in 200 x 45 Hyspan LVL joists. So I will probably put in proper timber floorboards then. Thanks for you advice.

[rod@plasterbrok]

At Clark Rubber you can buy 40mm wide by 13mm rubber strips pefect for under the floor boards.

I have used this to make up my own resilient clips.

Cheers

Rod