Plant room layout / utilities / ducts etc

[JackOrion]

We are just going over plant room layout as trenches are being starting to be dug for services.

 

Architects gave us initial layout for plant room which is in the centre of the house (2 bed bungalow, with small brick outbuilding which will be used for workspace).

 

Simplified sketch is below with kit sizes to scale. Red arrows show ins and outs. Unsure how realistic this looks! Obviously keen to get it right before pipework is laid and any concrete poured.

 

As ever any comments more than welcome.

 

– We are building to passive principles so assuming all these should be coming up through the slab?

 

– Should everything come in using ducts? (other than the 125mm pre-insulated pipe?)

 

– Should these ducts be sealed / grommeted / something else?

 

– How best to choose position of incoming / outgoing ducts?

All new to us.. architects gave a general idea but not much else. Groundworks team are great but not experienced with passive side of things.

 

Many thanks in advance 🙂

 

 

[JohnMo]

Why do you need a buffer in the plant room or at all?

 

Have you considered bend radius to get the 32mm duo piping into the plant room?

 

I would get the UFH manifold and cylinder next to each other and make the plumbing super simple. As said dump the buffer.

 

Why not have the ASHP the other side of the external wall and take everything through the wall?

[JackOrion]

29 minutes ago, JohnMo said:

Why do you need a buffer in the plant room or at all?

 

Have you considered bend radius to get the 32mm duo piping into the plant room?

 

I would get the UFH manifold and cylinder next to each other and make the plumbing super simple. As said dump the buffer.

 

Why not have the ASHP the other side of the external wall and take everything through the wall?

 

Buffer was in architects' floor plan, heating engineer did also spec one but I will double check whether this is needed.

 

 

 

The ASHP was on the other side of external wall on the original plan, but the path there is only 1.5m wide between house and retaining wall, so there isn't room unfortunately.

 

[Nickfromwales]

I’d go for a minimum of 250L for the UVC, possibly even 300L, so you can heat it far cooler (50-55°), so theres less latent losses snd more volume to store off peak energy or diverted PV etc. 200L is very small for an ASHP even if it’s just “the two of you”. 

 

You’ll need a second, smaller duct for the car charger for data / comms and to bring the CT clamps to the meter; if the meter is at the boundary then you need to work out where the CT clamps need to go and duct accordingly.

 

Rigid BT56 duct is the only duct your’e allowed to use for telecom, which they usually supply you for free.

 

Assuming the exported heating is for keeping you warm in the outbuilding, consider a large fan coil out there so it’ll cool and heat (remember that it’ll need a condensate drain); note: fan heaters give almost instant heat (and cool) vs a radiator. 

[JackOrion]

5 minutes ago, Nickfromwales said:

I’d go for a minimum of 250L for the UVC, possibly even 300L, so you can heat it far cooler (50-55°), so theres less latent losses snd more volume to store off peak energy or diverted PV etc. 200L is very small for an ASHP even if it’s just “the two of you”. 

 

You’ll need a second, smaller duct for the car charger for data / comms and to bring the CT clamps to the meter; if the meter is at the boundary then you need to work out where the CT clamps need to go and duct accordingly.

 

Rigid BT56 duct is the only duct your’e allowed to use for telecom, which they usually supply you for free.

 

Assuming the exported heating is for keeping you warm in the outbuilding, consider a large fan coil out there so it’ll cool and heat (remember that it’ll need a condensate drain); note: fan heaters give almost instant heat (and cool) vs a radiator. 

 

Will double check cylinder size, many thanks for that. I missed the cable duct for car charger from the sketch.. that should have been on there as was spec'd by electrician. Good spot.

 

The outbuilding is simple brick building (1900 ish) – but we insulated the floor with limecrete (https://mikewye.co.uk/product-category/limecrete-floor-systems/) and fitted UFH pipework in advance of house build, at the time thinking that would be our best option.

[JackOrion]

In terms of other services / ducting coming in, is it best for these to come through the slab in the same area of the room and distribute from there? Are they in one single opening in the slab or kept separate?

[JohnMo]

31 minutes ago, JackOrion said:

 

Will double check cylinder size, many thanks for that. I missed the cable duct for car charger from the sketch.. that should have been on there as was spec'd by electrician. Good spot.

 

The outbuilding is simple brick building (1900 ish) – but we insulated the floor with limecrete (https://mikewye.co.uk/product-category/limecrete-floor-systems/) and fitted UFH pipework in advance of house build, at the time thinking that would be our best option.

Why not put heat pump at the out building and then pipe to house? unless the outbuilding is huge the 32mm pipes sound over kill. We have a similar out building and have piped in 15mm (around 10m each way).

 

We have 210L and have never run short of water even when we have an additional 4 staying with us. We heat to 53 degs generally. Not sure I would want to heat an additional 100L every day just in case.

 

PV diversion isn't worth it, export it first.

[Gone West]

50 minutes ago, Nickfromwales said:

200L is very small for an ASHP even if it’s just “the two of you”. 

We had 185L heated by EASHP to 45C and the 'two of us' never ran out of DHW in the three years we lived there.

[Russell griffiths]

Do you need a drain to go in there for the cylinder ?

[JackOrion]

11 minutes ago, Russell griffiths said:

Do you need a drain to go in there for the cylinder ?

 

I will ask the question, thanks.

[JackOrion]

2 hours ago, JohnMo said:

Why not put heat pump at the out building and then pipe to house? unless the outbuilding is huge the 32mm pipes sound over kill. We have a similar out building and have piped in 15mm (around 10m each way).

 

We have 210L and have never run short of water even when we have an additional 4 staying with us. We heat to 53 degs generally. Not sure I would want to heat an additional 100L every day just in case.

 

PV diversion isn't worth it, export it first.

 

There's no room around the outbuilding for the heat pump either unfortunately – we're building on the site of an old walled garden on a hillside, and have neighbouring properties on all sides.

Outbuilding is about 45sqm total, although only 30sqm has UFH pipes in. (the remaining 15sqm has a cellar)

[Nickfromwales]

13 hours ago, Gone West said:

We had 185L heated by EASHP to 45C and the 'two of us' never ran out of DHW in the three years we lived there.

It's 'doable', but leaves very little headroom to stuff free or v cheap electricity into the UVC as an 'energy balloon'. The more free juice you can store = the longer before you need to lean on the heat source to replenish it.