Moonshine

This, with sound the devil is in the details!! Think of it like water, where there is a weakness (not just gaps) it will get through.

i don't think that cavity is sealed anymore! ?

Tell me about it, I submitted my pre app 10 weeks ago, and so far not heard anything other than me chasing and my app hasn't been assigned an officer yet

Thanks, that sounds a mind-field and i might look at diverting the existing drain down the side of my house to the front and a new sewer connection, this would mean i would have no issues with the new house/drain interaction, requirements of the sewerage company, legal knock-ons. The down side is more work and cost with that work and new sewer connection. Actually come to think of it there is another way, that means that i don't have to have the cost of a new sewer connection and the new house/drain interaction issue and build at the orange, with the adoptable sewer built to the requirements of the sewerage company.

I would say its a drain as its all on my land at the moment and i am the only one served on that run, if have a look at the blue line in the attached (NTS), at the plot boundary at the road it connects to a communal sewer. The black vertical line in the middle is the proposed plot boundary, so if that land / house was sold they would own the drain that serves my house, i don't know about the legal implications of this. I could take the drain to the right of the black vertical line but this would involve more digging, a new waste connection and cost.

I am looking to put a house and garden on a part of my plot where the existing drain is. Ideally I don't want to move the drain too much and I think there is space for it to go down the side of the new house. The question is how much space from the house is needed to fit a drain pipe to allow future access if the is any issues? Could it be housed in concrete culvert to minimise access issues in the future? How deep does it need to be? The other thing is there any issues of having your drain on someone else's land?

Chuffing heck that is some build up, was that selected for thermal reasons?

Yes they are/should be for sound reduction (Rw) in particular cases, this is not a building regulation requirement but maybe required from planning if its a noisy site, to achieve suitable internal noise levels. Some manufactures will test in accordance with BS EN ISO 10140-2:2010, but you have to make sure that the quoted sound reduction (Rw) are for the glazing panels, including frames and seals. A lot of things quoted are for the glazing element but not the frame. A typical double glazed unit (6mm/12mm/6mm) will give an Rw 30-32 dB, assuming that frame and seals are good. not quiet that straight forward, as depends how 'open' the window is, the source and window type https://www.napier.ac.uk/~/media/worktribe/output-246785/twfrepnanr116pdf.pdf

I had seen those, but that would be a last ditch solution to fall back on. I want to see if i can provide enough area in a 'non-standard' area, and even the guidance i gave could be adopted with some compromise.

My local authority will likely put a condition on any application that vehicles are able to enter and exit the site a curtilage in a forward gear to provide a safe and suitable access. They refer to only one turning layout in guidance notice, such as the one below; I am interested if there is any potential departure from this arrangement, and how i would go about proving an alternative solution can work?

I am thinking of what the existing floor build up is where you are taking the ceiling down (between ground and first floor), the ground floor construction is fairly unimportant acoustically. As for the stud, presuming that you are going for timber i would suggest two layers of 12.5mm soundbloc either side of the stud, with 25mm insulation (APR1200) in the cavity this gives you Rw 46 dB (above min requirement of Rw 40 dB). Bump the cavity insulation thickness and density up a bit will give likely give you 1-2 dB increase in performance. But if you want to go over this, adding a resilient bar to one side and having 50mm of insulation will give you Rw 56 dB (also have a look at the white book for suggested detailing p243). https://www.gyproc.ie/sites/default/files/A046005.pdf This would likely deal with the airborne sound pretty well, but as its a lightweight partition it won't be as good as a masonry wall for low frequency noise. As its a washing machine and tumble dryer, make sure that these are not touching / connected to walls as to allow structure borne noise, and maybe even a resilient mat on the floor to decouple it from the floor slab if its a shared slab to the room next door.

What is the existing floor build up? How much space have you got free for the stud wall as this will have an impact on the degree of sound insulation you can achieve.

Have a look at build up 4 in the attachment, Rw 41 dB in the table

Am I right in thinking you are specing just internal walls to meet Rw 40 dB? Are you looking for this as a minimum or going over and above? Based on the rockwool with 38×75 timber studs at 600mm centres and 1 layer 12.5mm acoustic rated plasterboard (11 kg/m²) each side and Insulation of a minimum of 50mm of ROCKWOOL FLEXI, this will give you 40 dB. It's interesting because British gypsium indicate you can achieve the 40 dB with 65mm of apr1200 which is 12kg/m3 density, and wallboard. For myself I would be looking not to use batts but rolls of mineral / glass wool or polyester and filling the cavity as much as possible without compression. Bearing in mind that once you get some fluffy stuff in the cavity of decent density the greatest gains you are going to get are increase density of boards, double boarding, resilient bars, or independent studs. In this case with known studs if you really want to increase the acoustics in key areas use mineral wool rolls and increase density of boards or double board.

I will be very interested in how this plays out as I have a pre-app meeting in the next few weeks. One tip thought don't let on that your online handle is policy sucks.

Internal walls like this need to achieve a min Rw 40 dB sound reduction (ADE requirement E.2), the British Gypsum white book gives an minimum example to achieve this as 63 x 38mm studs, 65mm isover APR 1200, and 1 layer of 12.5mm wall board either side (system ref A026012), though there are other ways to skin a cat but that involves Soundbloc and no insulation. But at the end of the day, having privacy between rooms is needed, and you may want to go over the minimum. Note however that the ADE requirement E.2 does not apply to internal walls that have a door, or on walls that separates an ensuite toilet from the bedroom it serves. In areas where you want increased acoustic privacy fill the cavity width with mineral wool insulation, 12-24 kg/m3 density, but don't over fill and compress it, and put two layers of 15mm Soundbloc on either side. I would only put a OSB board liner (probably 12mm ) between the stud and plasterboard where you are looking to hang fixtures such as sinks, cabinets, kitchens. As for bathrooms you may need to go for moisture resistance plaster, and probably 9mm hardie baker or similar where it may get wet (e.g. showers).

i suggest sketchup, but use a older version rather than the online system. I started with a simple model of my house but have ended up making a 3D model of the immediate local area including terrain, to guide how any developments would change the site.

Cheers, I am just thinking about layouts and setting out general space requirements, detailed design of retaining walls will be based on SE requirements

thanks for the pointers, very useful

I am looking to build on a sloped site, as such some of the external walls on one level of the proposed house will be a retaining wall with habitable rooms inside. My question is, in these spaces would you build the retaining wall, have a cavity with thermal insulation inside and the internal leaf, or something else?

Thanks for your thoughts, and i agree that M4(2) or M4(3) planning condition dependent, but M4(2) or M4(3) are 'optional requirements', see https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/540330/BR_PDF_AD_M1_2015_with_2016_amendments_V3.pdf. So, if the council does not set it as a planning condition then it just has to be M4(1), having looked a house locally that was granted outline planning permission early this year, there is no planning condition stating it has to be M4(2) or M4(3), so i take that as being M4(1) as the norm, though it i am ever granted permission without said condition i will be getting written confirmation that the intent is M4(1) so there would be no issue with BC.

Having looked at the issue a bit more, i don't know if i need a ramp. My local council highlights that not all dwellings need to be entirely wheelchair accessible and requires that 5% of new houses on a development need to be wheelchair accessible. Now what i am not sure of is how they will look an just a single house development. Also in regard Approved Document M, the 2016 amendments, introduced 3 categories, and planning portal indicates that a ramp, Categories 2 and 3 apply only where required by planning permission. https://www.planningportal.co.uk/info/200135/approved_documents/80/part_m_-_access_to_and_use_of_buildings So i think that i will design based on it being a Cat 1 building, but think how i could incorporate a ramp. Edit, i have just seen that the steepest ramp i could have is 1:12 in max 5 m lengths, meaning i would need 30m of sloped ramp in 6 lengths, plus the turns!

good point and I will increase the min cavity i think, you can get tongue and grooved PIR boards to negate this issue

Current thinking is brick and block, most of all the new builds i have seen recently are two leaves of 100mm block with 100mm cavity, typically with 50mm PIR board in the cavity, though with 100mm aerated block on the inner leaf.

Cheers, i will have a read through