Soundproof a Floor Question and Answer

Recent Question

I recently bought three rolls of Tecsound 50 to soundproof a floor where airborne noise was particularly bad from downstairs neighbours. I filled all gaps between skirting boards and the hardboard over the floorboards with acoustic sealand. Over this went the Tecsound 50, on top of this went Duralay System 10 underlay and on top went a heavy twist pile carpet. 

However this has made zero difference and I can still hear normal conversations and snoring from the flat below and believe that the only way forward is to rip everything back up and fully pack the floorspace with acoustic mineral wool. 

Do you have a heavier grade than the 45Kg AMW? I understand that 60 to 80Kg is optimal. Also, the floorspace in question was covered by exactly two rolls of Tecsound 50 – how many slabs would be required to cover the same space (given this will be packed between joists.)

Our Answer

Thank you for your email and the feedback on the acoustic performance you have so far experienced.  As long as flanking noise is not skirting round the floor, the application of mass is the best way to help block and reduce noise from the other side.  With the application of 2 layers of Tecsound 50, 10kg per sq mtr of mass would be added to the floor.  This will have had an effect at reducing noise but noise at night is much more difficult to address particularly with low frequency snoring.

Lifting your floorboards to install acoustic mineral wool will not make a huge difference although always beneficial.  Using the correct density AMW you will achieve an improvement of around 2dB and on its own, with no additional soundproofing measures, will not be an audible improvement but worthwhile as part of an overall upgrade using additional soundproofing materials.

I fear that there is not an effective solution to reduce the noise you are experiencing from below at night because this is a time when all of your normal background noises are switched off and you are trying to sleep.  This is a time when you are more aware of noise that would not disturb you during the day.

If your budget allows and you are prepared to lift the floorboards, by all means install 100mm of AMW100 acoustic mineral wool as a loose fit between the joists.  A denser AMW will not perform any better and could make the noise issue worse.  Once installed, screw back the floorboards, seal and refit with at least two layers of Tecsound.  Then instead of using the underlay you bought that has no value at reducing airborne noise, use our 15mm QuietFloor Plus acoustic underlay instead.  This will be adding a further 15kg of mass to the floor per sq. mtr. and far more effective than the underlay you have at present.  The underlay you have is only tested to reduce impact noise which is not what you are looking for.

More information on our QF+ underlay and AMW can be viewed on our web site via the following links

QuietFloor Plus

Acoustic Mineral Wool

Current prices are also on our web site.

For more information on all of our acoustic products go to our web site www.keepitquiet.co.uk or call us on 01993704981