Help- Building control have asked for M&E design (heating, ventilation, hot water)

[Wadrian]

Hi everyone

 

just broke ground yesterday for our self build. I Informed the building control that we should be ready in next 2 weeks for the foundation inspection. 
 

I had an email from building control to say they will not come to site until they have receive our 

1. M&E design (heating, ventilation, hot water)

 

is this something I would get a company to do? We are having a Grant ASHP and the manufacturer has designed a suitable tank and cylinder etc. we are also having UFH.

 

Please can anyone advise on How do I go about getting an M&E design? Is it one design or does it require multiple plans from various trades? 

 

thanks for any replies in advance 

Edited yesterday at 22:39 by Wadrian

[Tony L]

Well, yes, if you're not going to do it yourself, then you'll have to pay somebody to do it.  You could get an M&E consultant, such as @Nickfromwales, who posts here a lot, to do the whole lot, or you might get one company to deal with CH & hot water, & a separate company to deal with MVHR, if that's what you're having.  & if you're not having MVHR, I should think you just need to mention the trickle vents in the windows & give the spec' of the extractors in the bathrooms & kitchen.

 

Somebody who knows a lot more than me will be along to help you out tomorrow. 

[Roger440]

Is this actually a requirement now?

 

I cant believe everyone designs all that before you even start work on the house. 

[SteamyTea]

7 hours ago, Roger440 said:

Is this actually a requirement now?

 

I cant believe everyone designs all that before you even start work on the house. 

I doubt they want detailed design, just calculations that shows conformity with building regs i.e. heat losses at -3°C is 5 kW, here is a 5kW heat source.

[Nickfromwales]

11 hours ago, Roger440 said:

Is this actually a requirement now?

 

I cant believe everyone designs all that before you even start work on the house. 

I can’t believe anyone wouldn’t! 
 

Early design / planning before the foundation goes in is essential, as otherwise it’s just best guesswork; the birthplace of compromise or unnecessary costs to rectify later when you then see how it fecks up 1st fix etc. 

 

Fail to prepare, prepare to fail. 

[JohnMo]

12 hours ago, Wadrian said:

just broke ground yesterday for our self build. I Informed the building control that we should be ready in next 2 weeks for the foundation inspection. 
 

I had an email from building control to say they will not come to site until they have receive our 

1. M&E design (heating, ventilation, hot water)

You wouldn't have got to the breaking ground stage in Scotland without the design.

 

You will need full ventilation calculation - so if MVHR all room flow and extract rates. Other ventilation system, trickle vent sizing and fan selection to meet the chosen ventilation scheme and house airtightness target.

Heat loss calculation - this in Scotland is provided by an as-deigned SAP report.  This also provide hot water usage calculation. But you will most likely have to show how you control usage of hot water, via choice of mixer taps etc.

Heat source will need to match heat loss and DHW usage.

 

But as @Nickfromwales says, all this shouldn't guess work for later. If MVHR you need routs for ducts planned, if dMEV know where you need holes in walls, electrics routed too etc. Location of cylinder and UFH manifold(s) and how you get pipes from ASHP to cylinder and UFH manifolds.

 

Read building regs for each section you have been asked for and just follow the rules as set out, put it on paper submit.  Then take a good look at the drawings and see what you actually need to do and plan now, you may need to go back to the architect or structural engineer etc to make things work for you.

[Nickfromwales]

12 hours ago, Wadrian said:

Hi everyone

 

just broke ground yesterday for our self build. I Informed the building control that we should be ready in next 2 weeks for the foundation inspection. 
 

I had an email from building control to say they will not come to site until they have receive our 

1. M&E design (heating, ventilation, hot water)

 

is this something I would get a company to do? We are having a Grant ASHP and the manufacturer has designed a suitable tank and cylinder etc. we are also having UFH.

 

Please can anyone advise on How do I go about getting an M&E design? Is it one design or does it require multiple plans from various trades? 

 

thanks for any replies in advance 

If the heat loss / system sizing calcs are in it, then ASHP spec in their quote should hold sufficient info for them to be silenced. Tell BCO they’ll give you the G3 certification etc too.

 

Re MVHR etc, just tell them it’s too early to decide on a system or supplier, but that whatever arrangement you end up going for will be certified and accompanied by any other (relevant) compliances and a full ventilation certificate. Again, tell them you’re currently I decided but that they can assume trickle vents and basic mechanical fans for the get go.

 

The gaps in your understanding of how these systems can benefit you is your concern not theirs, also you really should make yourself forearmed with things like the correlation between airtightness and a great end result with MVHR, vs you not beating natural infiltration rates and are then just pumping cold air into the house all winter.

 

M&E is a whole, so best to join the dots before doing much more, just for yourself.

Don’t just pay this lip service, it’s about making a high performance / low cost (& maintenance) and comfortable future-proofed home for yourselves too!

[Nickfromwales]

37 minutes ago, JohnMo said:

You wouldn't have got to the breaking ground stage in Scotland without the design.

 

You will need full ventilation calculation - so if MVHR all room flow and extract rates. Other ventilation system, trickle vent sizing and fan selection to meet the chosen ventilation scheme and house airtightness target.

Heat loss calculation - this in Scotland is provided by an as-deigned SAP report.  This also provide hot water usage calculation. But you will most likely have to show how you control usage of hot water, via choice of mixer taps etc.

Heat source will need to match heat loss and DHW usage.

 

But as @Nickfromwales says, all this shouldn't guess work for later. If MVHR you need routs for ducts planned, if dMEV know where you need holes in walls, electrics routed too etc. Location of cylinder and UFH manifold(s) and how you get pipes from ASHP to cylinder and UFH manifolds.

 

Read building regs for each section you have been asked for and just follow the rules as set out, put it on paper submit.  Then take a good look at the drawings and see what you actually need to do and plan now, you may need to go back to the architect or structural engineer etc to make things work for you.

On a current client project we’ve moved steels about and altered doorways, all so simple (and virtually free) to do, when it’s just a click of a mouse and the house only exists on a screen.

 

So many poor architects out there even today, still not paying homage to plant space / transits / integration of the M&E into the fabric of the build, and worse; it’s gone past crazy and now it’s just embarrassing. And they charge handsomely for delivering this crap level of detail.

 

One client had been told by his architect to make the house airtight, but he “doesn’t like” MVHR so had recommended trickle vents and mechanical fans ffs.

What a tool !

[Adrian Walker]

1 minute ago, Nickfromwales said:

One client had been told by his architect to make the house airtight, but he “doesn’t like” MVHR so had recommended trickle vents and mechanical fans ffs.

What a tool !

An architect should be struck off for saying that. 

[Roger440]

1 hour ago, Nickfromwales said:

I can’t believe anyone wouldn’t! 
 

Early design / planning before the foundation goes in is essential, as otherwise it’s just best guesswork; the birthplace of compromise or unnecessary costs to rectify later when you then see how it fecks up 1st fix etc. 

 

Fail to prepare, prepare to fail. 

 

I gues my understanding of "design" might be slightly different from others.

 

So, do you need to specify you will will use a 6kw heat pump, or do you need to say it will be a valiant heat pump with a pipe run secured to a specific wall etc. The latter would seem a tall order and a bit restrictive. 

 

Clearly locating service ducts etc through a foundation are a no brainer.  Thats not how i interprated the OP's post.

 

 

 

[Nickfromwales]

3 hours ago, Roger440 said:

 

I gues my understanding of "design" might be slightly different from others.

 

So, do you need to specify you will will use a 6kw heat pump, or do you need to say it will be a valiant heat pump with a pipe run secured to a specific wall etc. The latter would seem a tall order and a bit restrictive. 

 

Clearly locating service ducts etc through a foundation are a no brainer.  Thats not how i interprated the OP's post.

 

 

 

Yup. Just throw them some genetic stuff and see what they quibble over, basically.

 

One architect had the client spend £1k on an MVHR design, which I got them to refund as it was a bag-o-💩. 
 

Totally unnecessary at this early stage to give any more detail than the very basics. 

[Nickfromwales]

4 hours ago, Adrian Walker said:

An architect should be struck off for saying that. 

The architect built his own house this way!! I went for a 3-way meeting and just couldn’t believe the tripe falling out of his mouth. 
 

Turns out he’s mostly versed in commercial projects, ffs, so afaic it’s time for him to go bye bye. 

[Alan Ambrose]

FYI, for MVHR, I used both the spreadsheet here on ‘t ‘ub and, for comparison, the Ubbink calculator. Then there’s a bit of common sense re air & duct routes, ceiling heights, valve positions. Detailed but not rocket surgery as they say.

[JohnMo]

All your numbers are below, just apply them to your house and then balance the the flow and extract.