Will lining the party wall stop me hearing my neighbours?

It will reduce airborne noise such as speech and television, provided the wall is genuinely the path and every edge is sealed. It will not produce silence, and it will not touch footfall from above or bass through the structure. Diagnose the path before ordering.

How many rolls do I need for one bedroom wall?

A 4 × 3 m wall is 12 m². Allow about 20% for overlaps at the joints and offcuts, so order 15 m² — three whole 5 m² rolls, since MLV is sold in whole rolls only.

Do I have to demolish the existing wall?

Normally not. The usual approach is to build over it: MLV bonded to the surface, joints taped, every edge sealed, then overboarded with 12 mm plasterboard. That adds about 20 to 30 mm per face, so check door frames, skirtings, sockets and any wall-mounted air-conditioning unit first.

Can I fix footsteps from the floor above with wall treatment?

No. Impact noise travels through the slab. Wall linings do not reach it. The realistic options are a resiliently hung ceiling, which costs head height, or soft flooring in the unit above.

Do I need permission in a condominium?

The wall between units is usually common property, so notify the juristic person before starting and expect restrictions on drilling into it and on working hours. In a rented unit, agree reinstatement in writing first.

Is BB830 the right grade, or should I pay for BB830LF?

BB830 for ordinary domestic noise — speech, television, general living. BB830LF is formulated for low-frequency work and costs more; it is worth it only where bass is genuinely the complaint, and even then the result comes from the build-up rather than from the sheet.

Soundproofing homes and condominiums

What residential noise actually is

Domestic complaints fall into a small number of types, and the type decides whether any of this is worth buying. Speech and television from the unit next door is airborne noise through a wall, and that is the case mass is good at. Footfall, dropped objects and furniture dragged across a tiled floor above is impact noise through the slab, and mass on a wall does nothing for it. Bass from a sound system is airborne at the top of its range and structure-borne at the bottom. Traffic and BTS noise arrives through the glazing, not the wall.

Before ordering anything, listen on a night when the noise is present. Move along the wall with your ear close to the surface and pause at the middle of the wall, the door edge and its undercut, the air-conditioning penetration, each socket and switch, the window perimeter, and directly under the ceiling line. The loudest point is where the first money goes. It is very often not the wall.

Which grade, and why

BB830 is the residential grade. It is nominally 5 kg/m² at about 3 mm according to the manufacturer’s datasheet, reference BB830/20/v2, and in a condominium that ratio is the whole argument: floor area in Bangkok is expensive, and this delivers useful mass in about 3 mm rather than in a 100 mm block wall. The material alone is STC 32 at 3 mm, a laboratory value from the manufacturer; a finished wall in an occupied building normally lands 5 to 10 dB below any published figure.

The other grades are not the answer here. BB830FR exists for work carrying a fire requirement, which a private dwelling normally does not, and BB830LF is formulated for low-frequency work and costs more than a domestic speech problem justifies. Where the complaint really is bass through a party wall, that is a different page and a different build-up.

Typical residential scope. Order about 20% over the measured area for overlaps at the joints and offcuts. MLV is sold in whole 5 m² rolls only.
What is being treated	Measured area	Order	Also needed
One bedroom party wall, 4 × 3 m	12 m²	3 rolls (15 m²)	BA990 adhesive, BA890 sealant, BA650 putty pads, door seals
Bedroom party wall plus the corridor wall	22 m²	6 rolls (30 m²)	As above, and seal both door sets
Townhouse party wall, 6 × 3 m	18 m²	5 rolls (25 m²)	As above, and close the roof void over the wall line
Home office or study, one wall	9 m²	3 rolls (15 m²)	BA990, BA890, door seals
Ceiling under a noisy unit, one bedroom	12 m²	3 rolls (15 m²)	Resilient hangers or an independent ceiling frame — mass alone does not fix footfall

The order of work

Seal the door: perimeter seals and a drop seal or threshold. Listen again before ordering material.
Back the socket and switch boxes on the party wall with BA650 putty pads.
Pack and seal every service penetration with BA890. Expanding foam is not an acoustic seal, and rigid mortar around a pipe makes a solid bridge.
Close the ceiling void at the party wall line and seal that closure. Skipping this undoes most of the work below it.
Bond BB830 to the wall with BA990, overlapping the sheets at the joints and taping them closed.
Seal head, base and both sides with BA890, then overboard with 12 mm plasterboard and seal the board perimeter again before skimming.

What not to spend money on

Egg-crate foam and decorative acoustic panels. They are porous and light, add no meaningful mass, and do nothing about a neighbour. They reduce echo in your own room, which is a problem you probably do not have.
Heavy curtains, for anything beyond a little high-frequency window leakage and some reverberation.
Carpet and rugs, if the complaint is footfall from above. They help the unit below you, not you.
Acoustic paint and thin sprayed coatings. Nothing a few tenths of a millimetre thick adds meaningful mass.
A second layer of MLV over a first layer that was never sealed. Sealing the first layer properly is worth more than doubling the material.
Lining three walls before diagnosing which one carries the sound. That is three times the cost for the same disappointment.

Where this is the wrong answer

Footfall and impact from the unit above. It travels through the slab and the frame. The options are a resiliently hung ceiling, which costs head height, or soft flooring in the unit above, which is cheaper and works better if the neighbour will cooperate.
A heavy party wall. A 150 mm concrete wall carries 250 to 400 kg/m²; adding about 5 kg/m² to it is a rounding error. Treat the door, the windows and the penetrations instead.
Traffic, expressway or BTS noise. That arrives through sliding aluminium windows, which leak at the sliding interface by design. Seal the frame and consider secondary glazing; internal wall work will not touch it.
Echo, harshness or poor speech intelligibility inside one room. That is absorption, not a barrier.
A rented unit where reinstatement has not been agreed in writing. MLV bonded and overboarded is not a reversible alteration.
Any wall where the perimeter cannot be sealed. A sheet that cannot be sealed at its edges will not deliver a result worth paying for.

Two residential sites the material was supplied for

IAC Acoustics (Thailand) supplied BlastBlock material for both projects below. Neither was installed by IAC; both were installed by others. The figures are quoted according to the project documentation held by BlastBlock. IAC did not take the measurements and has not verified them independently. Both are worth reading as illustrations of the point above: the path was a service, not a party wall.

A residence in Hua Hin had a bank of about five outdoor air-conditioning condensers standing against the house wall in a landscaped garden. A barrier was built along the line between the condensers and the garden and concealed within the existing planting. According to the project documentation the daytime level fell from 77 dB(A) to 62 dB(A), a reduction of 15 dB(A), mapped on a day dB(A) contour scale running from below 50 to 68 and over.

A riverside condominium in Bangkok had noise from a pipe run in a services riser reaching the apartments. The pipework was lagged and its supports changed for anti-vibration mounts. According to the project documentation the level fell from 71 dB(A) to 57 dB(A), a reduction of 14 dB(A) — achieved without touching a single wall.

Buying in Thailand

THB including 7% VAT, excluding VAT in brackets.
Item	Unit	Price
BB830 mass loaded vinyl	per m²	1,122 (1,049)
BB830, full roll	5 m² roll, about 25 kg	5,612 (5,245)
BA990 adhesive	per cartridge	428 (400)
BA890 sealant	per cartridge	321 (300)
BA650 putty pad	per pad	385 (360)

Stock is held in Bangkok and dispatched within one working day of cleared payment. Delivery is free nationwide over THB 20,000 excluding VAT; below that it is THB 500 to Bangkok and the surrounding provinces and THB 900 upcountry. Delivery is within Thailand only. A pre-cut 1 m² trial piece is available if you want to test a fixing detail first.