advice required on SEPARATING FLOOR in a flat above a shop

[paulx420]

hi.you will need to refer to the picture of the plan i enclose to understand this one.
i have recently made a separating floor in a flat above a shop.the floor consists of 25mm rockwool slab followed by 19mm plasterboard plank and 18mm t & g chip board.

the entire first floor was treated this way.the existing staircase leads upto the landing/hallway which is now approx 62mm higher.my problem is with this very huge step that has been created at the top of the staircase.
when you reach the top of the staircase you can either turn left or right and in either case you need to go through a fire door.
what i need to know is can i remove this separating floor in the small area of the landing between the 2 doors.alternatively is there a different way to achieve the same level of sound proofing without increasing the height of the floor.ie under the existing floorboards?
i dont think it will be practical to increase the size of each step to match the great big step at the top of the staircase.

plan attached .appreciate any good advice

 

[tony1851]

Have you done this through Building Control? If so, speak with the local buiding inspector. There is no easy way to sound-proof existing buidings up to Part E standard. The diagrams in the Approved Document are only suggestions for improving sound attenuation. If it's only a small area, the Inspector should be reasonable if the srep compromises safety. Just stick some batts under the floor.

 

[southwesterly]

Was there a flat there before? If so you may not need a separating floor. The best way to achieve a fire rated acoustic floor if you don't want to do any work in the shop is to use acoustic quilting between the joists supported on chicken wire trays. The floor boards are replaced with resilient flooring which is 18 or 22m t&g chipboard laminated with an acoustic rubber or foam layer under. That way your new floor would only be max 25mm higher, possibly less. If you need to pass a sound test then also get advice from the tester now.

 

[^woody^]

Keep the landing area immediately at the top of the stairs level with it, and slope the floor up to the corridor either side of it

 

[paulx420]

Have you done this through Building Control? If so, speak with the local buiding inspector. There is no easy way to sound-proof existing buidings up to Part E standard. The diagrams in the Approved Document are only suggestions for improving sound attenuation. If it's only a small area, the Inspector should be reasonable if the srep compromises safety. Just stick some batts under the floor.

its been passed by building control some time ago when separating floors weren't required(flat above a shop).i wasn't required to do this separating floor by anyone,i did it for my own satisfaction.i had converted another property recently and i used this kind of floor and thought i might as well do it in this flat as it was due for a refurb.it improves the sound and thermal insulation properties of the building.
when you say 'stick some battens under the floor',should i basically sink everything i done above the floor boards to below the floor boards?

thanks.

 

[tony1851]

Have you done this through Building Control? If so, speak with the local buiding inspector. There is no easy way to sound-proof existing buidings up to Part E standard. The diagrams in the Approved Document are only suggestions for improving sound attenuation. If it's only a small area, the Inspector should be reasonable if the srep compromises safety. Just stick some batts under the floor.

when you say 'stick some battens under the floor'

"batts" (ie sound-insulation batts), not "battens".