Mechanical and Electrical (M&E) designer or contractor

[Dave and Helen]

Hi,

 

It's been a whilst since I posted a topic on the site. Our project to convert a Severn Trent Pump House and Storage Tank into a new home gain planning permission back in November. We're currently working with our architect to get the building drawings finalised so we can get it all costed up ( not a small feet ). Our architect has recommended working with an M&E design consultant to determine a range of items, MVHR, PV, Rainwater Harvesting, SAP calculations, Underfloor Heating etc. This seems to be an expense we weren't expecting, and I'm curious to know if anyone else has, or would take this route. 

 

It seems we'll be paying just over £6k to have a company design a combined solution, to then provide a tender document to go to market and find a suitable contractor or more likely, contractors. Would it be better to find the right, experienced contractors in their field, and have them provide a design and fit servicem just concerned about one company, experienced as they maybe, detailing a solution that the individual contractors wouldn't agree with. 

 

I'd be interested in anyone who's taken this route and if it was beneficial and ultimately, worth the additional expense.  

 

Kind regards

 

Dave C

[Simplysimon]

mvhr - https://www.paulheatrecovery.co.uk/  https://www.greenbuildingstore.co.uk/services/mvhr-installation/  closer to you https://aspireecoenergy.co.uk/mvhr/

ufh - https://www.wundagroup.com/underfloor-heating/ closer to you http://www.peakunderfloorheating.com/site/

[SuperJohnG]

As abovejust go direct to suppliers ti get designs. Save yourself 6k.

 

I'd recommend wunda for UFH, many others would too. I'd also recommend BPC for MVHR supply seem to be helpful. 

 

For PV again straight to supplier like midsummer solar who will do you a free design and supply a kit. 

 

SAPeasy I'd recommend too. 

 

Then you can use local competent main contractor or individual trades to install to drgs. 

[ToughButterCup]

Whatever you do, @Dave and Helen, do your Due Diligence on any recommendation. A recommendation sourced from this site does not mean that the company has been endorsed by Build Hub. 

[Dreadnaught]

I agree with the others.

 

The manufacturer (Brink/Ubbink) designed my MVHR system (which I heavily tweaked).

UFH-pipe supplier designed the UFH layout.

In each case I paid for the design but that cost was deducted from the equipment purchase.

 

Plant-Room in general, and DHW/space-hearing systems can be a little trickier. In my case, an M&E expert did give me (hourly-rate paid) advice on those.

[Russell griffiths]

Forget the rainwater harvesting, unless it’s a planning condition. 

Total pain and waste of money. 

[Dave and Helen]

4 hours ago, Russell griffiths said:

Forget the rainwater harvesting, unless it’s a planning condition. 

Total pain and waste of money. 

Thanks for the feedback. It's not a planning condition, just seemed to make sense as we're on a water meter. 

Can I ask, why you found this to be a pain? 

 

Dave C

[Mr Punter]

My son is a building services engineer.  He just does the electrical design and other engineers in the firm do mechanical stuff and thermal modelling.  They do deal with housing but it would be for multi units, blocks and high rise, where there is more to consider.

 

For a one-off house you are probably better off discussing with the plumber and electrician where you want sockets, rads, boiler etc.  Your architect ought to be able to give some indicative locations.  You can mark up a plan by hand.

 

Get your MVHR firm to do the design for this.  They will charge but it is worth doing.

 

SAP calcs are very cheap and you can shop around for a quote.  You need them for Building regs and warranty.

[Mr Punter]

You can only use rainwater for limited non-potable applications, such as loo flush and washing machine.  You will then have a third water system in the house.  If it runs dry you will need to top it up.  The water must not be left to stagnate.  You will need to store it, treat it and pump it.  I have looked into this and you are wasting your time and money.

[PeterW]

27 minutes ago, Dave and Helen said:

Can I ask, why you found this to be a pain? 

 

So dependent on where you are in the UK, the requirements will be for a commercial solution which could cost upward of £3k for tanks pumps controls etc. I am in the Severn Trent area and with a house of 4, the water and sewerage costs are around £300/year. Rainwater harvesting will cover about 25-30% of your water usage so it is likely that you have something with a 25-30 year payback … with lots of moving parts and hassle.  
 

 

[Russell griffiths]

1 hour ago, Dave and Helen said:

Thanks for the feedback. It's not a planning condition, just seemed to make sense as we're on a water meter. 

Can I ask, why you found this to be a pain? 

 

Dave C

Water is cheap to buy.

, harvesting tank, digging, plumber are expensive. 

It just doesn’t add up. 

[Thorfun]

39 minutes ago, Russell griffiths said:

Water is cheap to buy.

, harvesting tank, digging, plumber are expensive. 

It just doesn’t add up. 

but you can use it to offset your water usage in the house, especially now there's a new net-zero water usage jobby in planning, right? I know for us it helped us to get through planning with regards to water usage in the house and the number of toilets/showers/baths/dishwashers etc we've planned.

 

we've got a RWH tank and didn't do it for any kind of financial return or saving, we wanted to reduce our reliance and demand on mains water. I hope to be in the new house for at least 30 years so if it eventually pays itself off then great! otherwise I won't be losing any sleep about the payback period.

 

As with other things, decisions don't have to be made just on the financial payback period of the technology.

[Dave and Helen]

Just want to send 

[Dave and Helen]

Just wanted to send a big thank you for all your comments and advice. There's still a lot to consider here, not just with rainwater harvesting but renewables in general. Thanks again.

 

Dave C

[Nickfromwales]

On 08/03/2022 at 15:27, Thorfun said:

we've got a RWH tank and didn't do it for any kind of financial return or saving, we wanted to reduce our reliance and demand on mains water. I hope to be in the new house for at least 30 years so if it eventually pays itself off then great! otherwise I won't be losing any sleep about the payback period.

Sadly the inevitable cost of replacement pumps will push you even further back on the breakeven. As you say you've already got the system anyways, be mindful then to maintain it and keep the sump strainer / filter clear and routinely check the cold feed sensor to make sure the pump NEVER EVER runs dry. That's instant suicide for the pump and bye-bye money. 

[puntloos]

Rainwater, I don't think you'd want to do a grey water install (using rainwater and maybe even sink water to flush toilets) - it complicates things hugely and it feels somewhat 'iffy' - I guess there should be handsoap in there to sterilize a bit but I'm not sure I'd want that type of water to be aerosolized into my bathroom by flushing..

 

Just catching rainwater and watering your lawn etc feels .. probably too hard for extensions but if you are doing a new build it's probably straightforward, we're already digging deep to get the full foundation ready.

 

As for a mech design- I had a designer who got me "80% there" and cost me a reasonable amount for the amount of work delivered. With it I'm going to tendering, but no guarantees.