Sound Proofing a Semi D.

Sister bought a house recently,semi D,nice house,good finish however the noise from the other property is what we both consider over the norm.Typical tiger builder,all flash finish but bugger all use if you can have a conversation with your neighbours when in your respective sitting rooms.

(This funnily enough doesn’t seem to be a problem upstairs,for whatever reason)

She want to remedy this asap.

what is the best solution?
How much will it cost?
Will it work?

Sound insulated plasterboard on the adjoining internal walls. Check the attic.

You lose an inch of space but get a bit of peace.

Probably your only hope for retrofit - although you would lose more than the inch as you should space the sound absorbing lining out from the wall a bit.
Flanking transmittal is probably happening here as well - so ideally you would want to seal the void areas to wall and ceilings - tricky and expensive with no 100% guarantee of success.
I presume it is full timber frame construction? A lot of details have to got just right with this type of construction to prevent a big sounding box being created.
Ah, lets hear it for 9" solid blockwork plastered to scud and scratch coats - mass is yer only man!

The problem in a lot of semi-d is transfernce across the upper floor floor beams. This adds to what I think you term flanking tranmission.

Surely though the dividing wall in a house such as the tyrannical built semi-d-non-design-battery-gaff, is block up to the roof me thought. It’s the subdividing structural wall is it not!

If it’s not it means the upper rooms are only stud partion separated and shared, that can’t be right because you know what that means… :open_mouth:

Locating all the places where the barrier has been compromised, and sealing to prevent air movement and thus sound will take some time I’d guess.

Thanks for the helpful replies lads.

The house is “traditional” bricks and mortar.I would guess its built right up top the spec that regs ask for and no more.Thats the problem the regs are next to useless for stuff like this allowing builders to build to them and no more,leaving thousands of property owners with this problem to one degree or another.

Further to the questions I asked,has anyone here experienced this problem and how much it cost to remedy etc?

Get the cause properly diagnosed by an acoustic engineer, and let them advise on options to address the problem(s). It could be bad workmanship or design oversight, or both, around electrical points, ventilation points, roof and ceiling spaces, bad joinery, mortar gaps, use of inappropriate insulation, or even simply something moved or changed in the course of a repair. And more. You’d be ill-advised to try and do this yourself unless the problem is very very obvious. While we’re on the topic, this is very similar to work to better insulate your house for heat. - I fail to grasp why so many people undertake work on this without getting an engineer out to investigate the building spec, and do a thermal imaging/analysis of the building envelope to see exactly where the heat is getting out, and what course of action will return the greatest benefits for the investment etc.

i looked into this before. Got a in touch with a specialist. Bottom line was that air borne sound (tv, conversation, farting in the shower etc) could be insulated against but structure borne ones not (doors slamming, kids running on wooden floors, electric showers etc).

A good acoustical engineer will be able to address most structure borne noise too. Essentially, they measure the frequencies being transmitted, and then by a variety of remedial actions, make changes in masses of the structural components, air gaps, use isolation hangers in place of the current fixings, simply add extra fixings to change the natural resonance etc. to address the problem.

Anyway - OP said a conversation could be held - this suggests air gaps. With structural noise, the sound would be completely indecipherable as only certain frequencies get through.

Have a similar problem in my house (though not half as bad as that described by the OP) - mine only kicks in if and when the kids next door start screaming as if they were being tortured ( which they’re not, I hasten to add ! )

Had an acoustic engineer pay me a visit about 2 years back and he suggested that whilst remedial work could be undertaken, there was no guarantees, as successfully sealing every possible airbridge through which sound might travel would be very difficult, not to mention structure-borne noises. He suggested trying to address the problem in one room and see if that rectified the situation before proceeding to do all rooms adjoining the party wall.

Cost for the single room would be about €1100 - I though it too much to stick on a horse called Maybe so we’ve persevered with trying to ignore the noise on the occasions it occurs. Thankfully, the kids are getting older and full on tantrums are lesser and lesser (and the neighbours’ kids aren’t too bad either. boom tish !)

Wait till they start having parites when the folks are away. :nin

I’ve doubts on whether it’s economically possible to get a semi-d with noise problems satisfactorily fixed.

It’s been a few years but think I heard quotes for around 10k for an entire party wall to be done, if you go all out there’s a lot of extra work like taking up floorboards, taking down ceilings, insulating around joists. Even after that you’ll have no guarantee the problem is fixed or substantially improved.

It’s the sort of price that makes people think they may as well move, or put up with it for a few years and move when the family gets bigger. And unlike most improvements it’s work that reduces value if buyers or their engineers notice.

The problem usually was blocklayers rushing through the job, big gaps between blocks hidden by slapped on mortar, no pointing. Have a look at wall in the attic to get an idea of what the bare wall looks like.

It’s typical of this country that an item that can affect quality of life, health, good relationships with neighbours is ignored but make the downstairs jacks too small and all of council hell breaks loose.

People don’t have x-ray vision on one hand but since the semi-d has been the bread and butter slop thrown up people should be wiser by now. Sadly this is not the case. The wrong people for so long have been in the driving seat. Most if nearly all that has been built will not stand the test of time. If it’s not even suitable now why would it be in the future, and you must ask the question why would such poor design continue to dominate the landscape.

Like I said, relatively some animals groups have more welfare lookout dictated in law than their human brethren.

A society built that thinks beyond money, would never let the Semi-D get off the drawing board. It’s a dead-end design. You couldn’t make me buy one if you gave me the money free of charge.

I live in a nothing-special semi-D built in 2004 and have no problems with noise, apart from the odd occasion where the neighbour is drilling.

That’s the root of the issue - semi-d format allows the maximising of house dwellings per hectare = greater return for developer/builder which is after all the entire raison d’etre for building anything in this country

Whether the end product is fit for purpose ( or indeed for habitation in some cases ) is a moot point and not important in the greater scheme of things…

Reversing that is a key to any “reform”. If you don’t see that then there is no real change only official “reform”.

The recent planning changes and certification underlined the raising of the asylum walls a few feet higher was go.

Whatever about developer profits, cities need density.

If all 470k ish households in Dublin were in detached houses on 1/4 acre, Dublin would occupy a circle 25km in diameter, excluding roads, schools, shops, recreational areas etc.

I’m sorry, blackdog. I’ll try to be a little quieter in the shower, in future :blush: .

It’s alright WaWa - they still think it’s just an electric shower!

Who’d a thunk it, your first gaff would be acoustically akin to the rows of pitched tents at Oxygen or Electric picnic.

The only difference I can think of is not hearing the sound of various tent alarms sounding early of a weekend morning as someone makes off with your gnipeels gab, hash, smodnoc, upmake but worst of all your elgrag to see you through the cold sleepless nights!

I hardly understood a word of that, but it did remind me of the droogs’ nadsat from A Clockwork Orange. :laughing: